From: Kurt Zeilenga Date: Sun, 7 Dec 2003 07:50:23 +0000 (+0000) Subject: Suck in latest I-D revisions X-Git-Tag: OPENLDAP_REL_ENG_2_1_MP~235 X-Git-Url: https://git.sur5r.net/?a=commitdiff_plain;h=43ffeda85d814e4e26a6483c32b63bad50377477;p=openldap Suck in latest I-D revisions --- diff --git a/doc/drafts/draft-ietf-ldapbis-authmeth-xx.txt b/doc/drafts/draft-ietf-ldapbis-authmeth-xx.txt index 312bd61115..4b2fff9ce8 100644 --- a/doc/drafts/draft-ietf-ldapbis-authmeth-xx.txt +++ b/doc/drafts/draft-ietf-ldapbis-authmeth-xx.txt @@ -1,9 +1,8 @@ - -Internet-Draft Editor: R. Harrison -Intended Category: Draft Standard Novell, Inc. -Document: draft-ietf-ldapbis-authmeth-05.txt March 2003 -Obsoletes: RFC 2829, RFC 2830 +INTERNET-DRAFT Editor: R. Harrison +draft-ietf-ldapbis-authmeth-08.txt Novell, Inc. +Obsoletes: 2251, 2829, 2830 26 October 2003 +Intended Category: Draft Standard LDAP: Authentication Methods @@ -37,87 +36,51 @@ Status of this Memo Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. +Copyright Notice + + Copyright (C) The Internet Society (2003). All Rights Reserved. + Abstract - This document describes LDAPv3 (Lightweight Directory Access - Protocol v3) authentication methods and connection level security - mechanisms that are required of all conforming LDAPv3 server - implementations and makes recommendations for combinations of these - mechanisms to be used in various deployment circumstances. + This document describes authentication methods and connection level + security mechanisms of the Lightweight Directory Access Protocol + (LDAP). + + This document details the simple Bind authentication method + including anonymous, unauthenticated, and plain-text password + methods and the SASL (Simple Authentication and Security Layer) Bind + authentication method including the use of DIGEST-MD5 and EXTERNAL + mechanisms. - Among the mechanisms described are - - - various forms of authentication including anonymous - authentication, password-based authentication, and certificate - based authentication - - the use of SASL mechanisms with LDAPv3 - - the use of TLS (Transport Layer Security) with LDAPv3 - -Harrison Expires September 2003 [Page 1] +Harrison Expires April 2004 [Page 1] - Authentication Methods for LDAPv3 +Internet-Draft LDAP Authentication Methods 7 October 2003 - - the various authentication and authorization states through - which a connection to an LDAP server may pass and the actions - that trigger these state changes. - - -1. Conventions Used in this Document + This document also details establishment of TLS (Transport Layer + Security) using the Start TLS operation. -1.1. Glossary of Terms - - The following terms are used in this document. To aid the reader, - these terms are defined here. - - - "user" represents any application which is an LDAP client using - the directory to retrieve or store information. - - - "LDAP association" is used to distinguish the LDAP-level - connection from any underlying TLS-level connection that may or - may not exist. - -1.2. Security Terms and Concepts - - In general, security terms in this document are used consistently - with the definitions provided in [RFC2828]. In addition, several - terms and concepts relating to security, authentication, and - authorization are presented in Appendix B of this document. While - the formal definition of these terms and concepts is outside the - scope of this document, an understanding of them is prerequisite to - understanding much of the material in this document. Readers who are - unfamiliar with security-related concepts are encouraged to review - Appendix B before reading the remainder of this document. - -1.3. Keywords + This document describes various authentication and authorization + states through which a connection to an LDAP server may pass and the + actions that trigger these state changes. - 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 RFC 2119 [RFC2119]. + This document also prescribes DIGEST-MD5 as LDAP's mandatory-to- + implement strong authentication mechanism. -2. Introduction +1. Introduction - This document is an integral part of the LDAP Technical - Specification [ROADMAP]. This document replaces RFC 2829 and - portions of RFC 2830. Changes to RFC 2829 are summarized in Appendix - C and changes to RFC 2830 are summarized in Appendix D. - - LDAPv3 is a powerful access protocol for directories. It offers - means of searching, retrieving and manipulating directory content, - and ways to access a rich set of security functions. + The Lightweight Directory Access Protocol (LDAP) [Protocol] is a + powerful access protocol for directories. It offers means of + searching, retrieving and manipulating directory content, and ways + to access a rich set of security functions. It is vital that these security functions be interoperable among all LDAP clients and servers on the Internet; therefore there has to be a minimum subset of security functions that is common to all - implementations that claim LDAPv3 conformance. + implementations that claim LDAP conformance. Basic threats to an LDAP directory service include: -Harrison Expires September 2003 [Page 2] - - Authentication Methods for LDAPv3 - - (1) Unauthorized access to directory data via data-retrieval operations, @@ -137,24 +100,32 @@ Harrison Expires September 2003 [Page 2] (7) Spoofing of directory: Tricking a client into believing that information came from the directory when in fact it did not, either by modifying data in transit or misdirecting the client's - connection. + connection. Also, tricking a client into sending privileged + information to a hostile entity that appears to be the directory + but is not. Threats (1), (4), (5) and (6) are due to hostile clients. Threats (2), (3) and (7) are due to hostile agents on the path between client and server or hostile agents posing as a server. - The LDAP protocol suite can be protected with the following security - mechanisms: + LDAP can be protected with the following security mechanisms: + + + +Harrison Expires April 2004 [Page 2] + +Internet-Draft LDAP Authentication Methods 7 October 2003 - (1) Client authentication by means of the SASL [RFC2222] mechanism - set, possibly backed by the TLS [RFC2246] credentials exchange + (1) Client authentication by means of the Secure Authentication and + Security Layer (SASL) [SASL] mechanism set, possibly backed by + the Transport Layer Security (TLS) [TLS] credentials exchange mechanism, (2) Client authorization by means of access control based on the requestor's authenticated identity, - (3) Data integrity protection by means of the TLS protocol or SASL - mechanisms that provide data integrity services, + (3) Data integrity protection by means of TLS or SASL mechanisms + with security layers that provide data integrity services, (4) Data confidentiality protection against snooping by means of the TLS protocol or SASL mechanisms that provide data @@ -167,22 +138,14 @@ Harrison Expires September 2003 [Page 2] mechanism. At the moment, imposition of access controls is done by means - outside the scope of the LDAPv3 protocol. - -3. Rationale for LDAPv3 Security Mechanisms - - - -Harrison Expires September 2003 [Page 3] - - Authentication Methods for LDAPv3 - + outside the scope of LDAP. + It seems clear that allowing any implementation, faced with the above requirements, to simply pick and choose among the possible alternatives is not a strategy that is likely to lead to interoperability. In the absence of mandates, clients will be written that do not support any security function supported by the - server, or worse, they will support only mechanisms like the LDAPv3 + server, or worse, they will support only mechanisms like the LDAP simple bind using clear text passwords that provide inadequate security for most circumstances. @@ -196,134 +159,258 @@ Harrison Expires September 2003 [Page 3] of user identities for backwards compatibility with non-LDAP-based authentication services. - The set of security mechanisms provided in LDAPv3 and described in + The set of security mechanisms provided in LDAP and described in this document is intended to meet the security needs for a wide range of deployment scenarios and still provide a high degree of - interoperability among various LDAPv3 implementations and - deployments. Appendix A contains example deployment scenarios that - list the mechanisms that might be used to achieve a reasonable level - of security in various circumstances. + interoperability among various LDAP implementations and deployments. + Appendix A contains example deployment scenarios that list the + mechanisms that might be used to achieve a reasonable level of + security in various circumstances. + + This document is an integral part of the LDAP Technical + Specification [Roadmap]. This document replaces RFC 2829 and + portions of RFC 2830 and RFC 2251. + +Harrison Expires April 2004 [Page 3] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + + +2. Conventions Used in this Document + +2.1. Glossary of Terms + + The following terms are used in this document. To aid the reader, + these terms are defined here. + + - "user" represents any human or application entity which is + accessing the directory using a directory client. A directory + client (or client) is also known as a directory user agent + (DUA). + + - "connection" and "LDAP connection" both refer to the underlying + transport protocol connection between two protocol peers. + + - "TLS connection" refers to a TLS-protected LDAP connection. + + - "association" and "LDAP association" both refer to the + association of the LDAP connection and its current + authentication and authorization state. + +2.2. Security Terms and Concepts + + In general, security terms in this document are used consistently + with the definitions provided in [RFC2828]. In addition, several + terms and concepts relating to security, authentication, and + authorization are presented in Appendix B of this document. While + the formal definition of these terms and concepts is outside the + scope of this document, an understanding of them is prerequisite to + understanding much of the material in this document. Readers who are + unfamiliar with security-related concepts are encouraged to review + Appendix B before reading the remainder of this document. + +2.3. Keywords + + 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 RFC 2119 [RFC2119]. -4. Bind Operation +3. Bind Operation The Bind operation defined in section 4.2 of [Protocol] allows authentication information to be exchanged between the client and - server. + server to establish a new LDAP association. The new LDAP association + is established upon successful completion of the authentication + exchange. + + -4.1. Unbound Connection Treated as Anonymous ("Implied Anonymous Bind") +3.1. Implied Anonymous Bind on LDAP Association - Unlike LDAP version 2, the client need not send a Bind Request in - the first PDU of the connection. The client may send any operation - request prior to binding, and the server MUST treat it as if it had - been performed after an anonymous bind operation. If the server - requires that the client bind before browsing or modifying the - directory, the server MAY reject a request other than binding, - unbinding or an extended request with the "operationsError" result. + Prior to the successful completion of a Bind operation and during + any subsequent authentication exchange, the session has an anonymous + +Harrison Expires April 2004 [Page 4] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + + LDAP association. Among other things this implies that the client + need not send a Bind Request in the first PDU of the connection. The + client may send any operation request prior to binding, and the + server MUST treat it as if it had been performed after an anonymous + bind operation. This authentication state on an LDAP association is + sometimes referred to as an implied anonymous bind. + +3.2. Simple Authentication + The simple authentication choice provides minimal facilities for + establishing an anonymous association or for establishing an LDAP + association based upon credentials consisting of a name (in the form + of an [LDAPDN] and a password. + + The simple authentication choice provides two different methods + for establishing an anonymous association: anonymous bind and + unauthenticated bind (see section 6.1). -4.2. Simple Authentication + The simple authentication choice provides one method for + establishing a non-anonymous association: simple password bind. - The simple authentication option provides minimal authentication - facilities, with the contents of the authentication field consisting - only of a cleartext password. Note that the use of cleartext - passwords is strongly discouraged over open networks when the - underlying transport service cannot guarantee confidentiality (see - section 8). +3.3. SASL Authentication Profile -4.3. SASL Authentication + LDAP allows authentication via any SASL mechanism [SASL]. As LDAP + includes native anonymous and plaintext authentication methods, the + "ANONYMOUS" [ANONYMOUS] and "PLAIN" [PLAIN] SASL mechanisms are + typically not used with LDAP. -Harrison Expires September 2003 [Page 4] - - Authentication Methods for LDAPv3 + Each protocol that utilizes SASL services is required to supply + certain information profiling the way they are exposed through the + protocol ([SASL] section 5). This section explains how each of these + profiling requirements are met by LDAP. + +3.3.1. SASL Service Name for LDAP + The SASL service name for LDAP is "ldap", which has been registered + with the IANA as a GSSAPI service name. + +3.3.2. SASL authentication initiation and protocol exchange + + SASL authentication is initiated via an LDAP bind request + ([Protocol] section 4.2) with the following parameters: - The sasl authentication option allows for any mechanism defined for - use with SASL [RFC2222] not specifically prohibited by this document - (see section 4.3.1). + - The version is 3. + - The AuthenticationChoice is sasl. + - The mechanism element of the SaslCredentials sequence contains + the value of the desired SASL mechanism. + - The optional credentials field of the SaslCredentials sequence + may be used to provide an initial client response for + mechanisms that are defined to have the client send data first + (see [SASL] sections 5 and 6.1). + + In general, a SASL authentication protocol exchange consists of a + series of server challenges and client responses, the contents of + +Harrison Expires April 2004 [Page 5] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + + which are specific to and defined by the SASL mechanism. Thus for + some SASL authentication mechanisms, it may be necessary for the + client to respond to one or more server challenges by invoking the + BindRequest multiple times. A challenge is indicated by the server + sending a BindResponse with the resultCode set to + saslBindInProgress. This indicates that the server requires the + client to send a new bind request, with the same sasl mechanism to + continue the authentication process. + + To the encapsulating protocol, these challenges and responses are + opaque binary tokens of arbitrary length. LDAP servers use the + serverSaslCreds field, an OCTET STRING, in a bind response message + to transmit each challenge. LDAP clients use the credentials field, + an OCTET STRING, in the SaslCredentials sequence of a bind request + message to transmit each response. Note that unlike some Internet + application protocols where SASL is used, LDAP is not text-based, + thus no Base64 transformations are performed on these challenge and + response values. Clients sending a bind request with the sasl choice selected SHOULD NOT send a value in the name field. Servers receiving a bind request with the sasl choice selected SHALL ignore any value in the name field. - The mechanism field in SaslCredentials contains the name of the - mechanism. The credentials field contains the arbitrary data used - for authentication, inside an OCTET STRING wrapper. Note that unlike - some Internet application protocols where SASL is used, LDAP is not - text-based, thus no Base64 transformations are performed on the - credentials. + A client may abort a SASL bind negotiation by sending a BindRequest + with a different value in the mechanism field of SaslCredentials, or + an AuthenticationChoice other than sasl. + + If the client sends a BindRequest with the sasl mechanism field as + an empty string, the server MUST return a BindResponse with + authMethodNotSupported as the resultCode. This will allow clients to + abort a negotiation if it wishes to try again with the same SASL + mechanism. + + The server indicates completion of the SASL challenge-response + exchange by responding with a bind response in which the resultCode + is either success, or an error indication. + + The serverSaslCreds field in the bind response can be used to + include an optional challenge with a success notification for + mechanisms which are defined to have the server send additional data + along with the indication of successful completion. + +3.3.3. Octet where negotiated security mechanisms take effect + + When negotiated, SASL security layers take effect following the + transmission by the server and reception by the client of the final + BindResponse in the exchange. + + Once a SASL security layer providing integrity or confidentiality + services takes effect, the layer remains in effect until a new layer + is installed (i.e. at the first octet following the final + BindResponse of the bind operation that caused the new layer to take + effect). + +Harrison Expires April 2004 [Page 6] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + + +3.3.4. Determination of supported SASL mechanisms - If any SASL-based integrity or confidentiality services are enabled, - they take effect following the transmission by the server and - reception by the client of the final BindResponse with a resultCode - of success. + An LDAP client may determine the SASL mechanisms a server supports + by performing a search request on the root DSE, requesting the + supportedSASLMechanisms attribute. The values of this attribute, if + any, list the mechanisms the server supports. - If a SASL security layer is negotiated, the client MUST discard all +3.3.5. Rules for using SASL security layers + + If a SASL security layer is negotiated, the client SHOULD discard information about the server fetched prior to the initiation of the - SASL negotiation. If the client is configured to support multiple - SASL mechanisms, it SHOULD fetch the supportedSASLmechanisms list - both before and after the SASL security layer is negotiated. This - allows the client to detect active attacks that remove supported - SASL mechanisms from the supportedSASLMechanisms list and allows the - client to ensure that it is using the best mechanism supported by - both client and server. (This requirement is a SHOULD to allow for - environments where the supportedSASLMechanisms list is provided to - the client through a different trusted source, e.g. as part of a - digitally signed object.) - - The client can request that the server use authentication - information from a lower layer protocol by using the SASL EXTERNAL - mechanism (see section 5.2.2.). - -4.3.1. Use of ANONYMOUS and PLAIN SASL Mechanisms - - As LDAP includes native anonymous and plaintext authentication - methods, the "ANONYMOUS" and "PLAIN" SASL mechanisms are not used - with LDAP. If an authorization identity of a form different from a - DN is requested by the client, a data confidentiality mechanism that - protects the password in transit should be used. - -4.3.2. Use of EXTERNAL SASL Mechanism - - The "EXTERNAL" SASL mechanism can be used to request the LDAP server - make use of security credentials exchanged by a lower layer. If a - TLS session has not been established between the client and server - prior to making the SASL EXTERNAL Bind request and there is no other - external source of authentication credentials (e.g. IP-level - -Harrison Expires September 2003 [Page 5] - - Authentication Methods for LDAPv3 - - security [RFC2401]), or if during the process of establishing the - TLS session, the server did not request the client's authentication - credentials, the SASL EXTERNAL bind MUST fail with a resultCode of - inappropriateAuthentication. Any client authentication and + SASL negotiation and not obtained through secure mechanisms. + + If the client is configured to support multiple SASL mechanisms, it + SHOULD fetch the supportedSASLmechanisms list both before and after + the SASL security layer is negotiated. This allows the client to + detect active attacks that remove supported SASL mechanisms from the + supportedSASLMechanisms list and allows the client to ensure that it + is using the best mechanism supported by both client and server. (In + particular, this allows for environments where the + supportedSASLMechanisms list is provided to the client through a + different trusted source, e.g. as part of a digitally signed + object.) + + If a lower level security layer (such as TLS) is negotiated, any + SASL security services SHALL be layered on top of such security + layers regardless of the order of their negotiation. + +3.3.6. Use of EXTERNAL SASL Mechanism + + A client can use the "EXTERNAL" SASL mechanism to request the LDAP + server to make use of security credentials exchanged by a lower + layer. If authentication credentials have not been established at a + lower level (such as by TLS authentication or IP-level security + [RFC2401]), the SASL EXTERNAL bind MUST fail with a resultCode of + inappropriateAuthentication. Any client authentication and authorization state of the LDAP association is lost, so the LDAP association is in an anonymous state after the failure (see [Protocol] section 4.2.1). -4.3.3. Other SASL Mechanisms - - Other SASL mechanisms may be used with LDAP, but their usage is not - considered in this document. - -4.4. SASL Authorization Identity - - The authorization identity is carried as part of the SaslCredentials - credentials field in the Bind request and response. +3.4. SASL Authorization Identity When the "EXTERNAL" SASL mechanism is being negotiated, if the - credentials field is present, it contains an authorization identity - of the authzId form described below. + SaslCredentials credentials field is present, it contains an + authorization identity. Other mechanisms define the location of the + authorization identity in the credentials field. In either case, the + authorization identity is represented in the authzId form described + below. - Other mechanisms define the location of the authorization identity - in the credentials field. - -4.4.1. Authorization Identity Syntax +3.4.1. Authorization Identity Syntax - The authorization identity is a string in the UTF-8 character set, - corresponding to the following ABNF grammar [RFC2234]: + The authorization identity is a string of [UTF-8] encoded [Unicode] + characters corresponding to the following ABNF grammar [RFC2234]: + +Harrison Expires April 2004 [Page 7] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + ; Specific predefined authorization (authz) id schemes are ; defined below -- new schemes may be defined in the future. @@ -343,84 +430,74 @@ Harrison Expires September 2003 [Page 5] userid = utf8string ; syntax unspecified The dnAuthzId choice allows client applications to assert - authorization identities in the form of a distinguished name. The - decision to allow or disallow an authentication identity to have - access to the requested authorization identity is a matter of local - policy ([SASL] section 4.2). For this reason there is no requirement - that the asserted dn be that of an entry in directory. + authorization identities in the form of a distinguished name to be + matched in accordance with the distinguishedName matching rule + [Syntaxes]. The decision to allow or disallow an authentication + identity to have access to the requested authorization identity is a + matter of local policy ([SASL] section 4.2). For this reason there + is no requirement that the asserted dn be that of an entry in + directory. - -Harrison Expires September 2003 [Page 6] - - Authentication Methods for LDAPv3 - The uAuthzId choice allows for compatibility with client applications that wish to assert an authorization identity to a local directory but do not have that identity in distinguished name - form. The format of utf8string is defined as only a sequence of UTF- - 8 encoded ISO 10646 characters, and further interpretation is - subject to prior agreement between the client and server. + form. The value contained within a uAuthzId MUST be prepared using + SASLprep before being compared octet-wise. The format of utf8string + is defined as only a sequence of of [UTF-8] encoded [Unicode] + characters, and further interpretation is subject to prior agreement + between the client and server. For example, the userid could identify a user of a specific - directory service, or be a login name or the local-part of an RFC - 822 email address. In general, a uAuthzId MUST NOT be assumed to be - globally unique. + directory service or be a login name or the local-part of an RFC 822 + email address. A uAuthzId SHOULD NOT be assumed to be globally + unique. - Additional authorization identity schemes MAY be defined in future + Additional authorization identity schemes may be defined in future versions of this document. -4.5. SASL Service Name for LDAP - - For use with SASL [RFC2222], a protocol must specify a service name - to be used with various SASL mechanisms, such as GSSAPI. For LDAP, - the service name is "ldap", which has been registered with the IANA - as a GSSAPI service name. - -4.6. SASL Integrity and Privacy Protections - - Any negotiated SASL integrity and privacy protections SHALL start on - the first octet of the first LDAP PDU following successful - completion of the SASL bind operation. If lower level security layer - is negotiated, such as TLS, any SASL security services SHALL be - layered on top of such security layers regardless of the order of - their negotiation. - -5. Start TLS Operation +4. Start TLS Operation The Start Transport Layer Security (StartTLS) operation defined in - section 4.13 of [Protocol] provides the ability to establish - Transport Layer Security [RFC2246] on an LDAP association. + section 4.13 of [Protocol] provides the ability to establish [TLS] + on an LDAP association. -5.1. Sequencing of the Start TLS Operation +4.1. Sequencing of the Start TLS Operation This section describes the overall procedures clients and servers must follow for TLS establishment. These procedures take into + +Harrison Expires April 2004 [Page 8] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + consideration various aspects of the overall security of the LDAP association including discovery of resultant security level and assertion of the client's authorization identity. Note that the precise effects, on a client's authorization identity, of establishing TLS on an LDAP association are described in detail - in section 5.5. + in section 4.2. -5.1.1. Requesting to Start TLS on an LDAP Association +4.1.1. Requesting to Start TLS on an LDAP Connection The client MAY send the Start TLS extended request at any time after - establishing an LDAP association, except that in the following cases - the client MUST NOT send a Start TLS extended request: - -Harrison Expires September 2003 [Page 7] - - Authentication Methods for LDAPv3 - - - - if TLS is currently established on the connection, or - - during a multi-stage SASL negotiation, or - - if there are any LDAP operations outstanding on the - connection. + establishing an LDAP connection, except: + + - when TLS is currently established on the connection, + - when a multi-stage SASL negotiation is in progress on the + connection, or + - when there are one or more outstanding LDAP operations on the + connection. The result of violating any of these requirements is a resultCode of - operationsError, as described above in [Protocol] section 14.3.2.2. + operationsError, as described in [Protocol] section 4.13.2.2. Client + implementers should note that it is possible to receive a resultCode + of success for a Start TLS operation that is sent on a connection + with outstanding LDAP operations and the server has sufficient time + to process them prior to its receiving the Start TLS request. + Implementors should ensure that they do not inadvertently depend + upon this race condition for proper functioning of their + applications. In particular, there is no requirement that the client have or have not already performed a Bind operation before sending a Start TLS @@ -432,11 +509,9 @@ Harrison Expires September 2003 [Page 7] other requests, and the server requires the client to establish a TLS connection before performing a particular request, the server MUST reject that request by sending a resultCode of - confidentialityRequired or strongAuthRequired. In response, the - client MAY send a Start TLS extended request, or it MAY choose to - close the connection. + confidentialityRequired or strongAuthRequired. -5.1.2. Starting TLS +4.1.2. Starting TLS The server will return an extended response with the resultCode of success if it is willing and able to negotiate TLS. It will return @@ -447,56 +522,47 @@ Harrison Expires September 2003 [Page 7] LDAP requests on the connection) MUST either begin a TLS negotiation or close the connection. The client will send PDUs in the TLS Record Protocol directly over the underlying transport connection to the - server to initiate TLS negotiation [RFC2246]. + server to initiate [TLS] negotiation. + -5.1.3. TLS Version Negotiation +Harrison Expires April 2004 [Page 9] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + +4.1.3. TLS Version Negotiation Negotiating the version of TLS or SSL to be used is a part of the - TLS Handshake Protocol, as documented in [RFC2246]. Please refer to - that document for details. + [TLS] Handshake Protocol. Please refer to that document for details. -5.1.4. Discovery of Resultant Security Level +4.1.4. Discovery of Resultant Security Level After a TLS connection is established on an LDAP association, both parties MUST individually decide whether or not to continue based on - the privacy level achieved. Ascertaining the TLS connection's - privacy level is implementation dependent, and accomplished by + the security level achieved. Ascertaining the TLS connection's + security level is implementation dependent and accomplished by communicating with one's respective local TLS implementation. If the client or server decides that the level of authentication or - privacy is not high enough for it to continue, it SHOULD gracefully + security is not high enough for it to continue, it SHOULD gracefully close the TLS connection immediately after the TLS negotiation has - completed (see [Protocol] section 4.13.3.1 and section 5.2.3 below). - -Harrison Expires September 2003 [Page 8] - - Authentication Methods for LDAPv3 + completed (see [Protocol] section 4.13.3.1 and section 4.2.3 below). + If the client decides to continue, it may gracefully close the TLS + connection and attempt to Start TLS again, it may send an unbind + request, or it may send any other LDAP request. - If the client decides to continue, it MAY attempt to Start TLS - again, it MAY send an unbind request, or it MAY send any other LDAP - request. - -5.1.5. Assertion of Client's Authorization Identity - - The client MAY, upon receipt of a Start TLS response indicating - success, assert that a specific authorization identity be utilized - in determining the client's authorization status. The client - accomplishes this via an LDAP Bind request specifying a SASL - mechanism of "EXTERNAL" [RFC2222] (see section 5.5.1.2 below). - -5.1.6. Server Identity Check +4.1.5. Server Identity Check The client MUST check its understanding of the server's hostname against the server's identity as presented in the server's - Certificate message, in order to prevent man-in-the-middle attacks. + Certificate message in order to prevent man-in-the-middle attacks. Matching is performed according to these rules: - - The client MUST use the server hostname it used to open the LDAP - connection as the value to compare against the server name as - expressed in the server's certificate. The client MUST NOT use - the any other derived form of name including the server's - canonical DNS name. + - The client MUST use the server provided by the user (or other + trusted entity) as the value to compare against the server name + as expressed in the server's certificate. A hostname derived + from the user input is to be considered provided by the user + only if derived in a secure fashion (e.g., DNSSEC). - If a subjectAltName extension of type dNSName is present in the certificate, it SHOULD be used as the source of the server's @@ -507,16 +573,21 @@ Harrison Expires September 2003 [Page 8] - The "*" wildcard character is allowed. If present, it applies only to the left-most name component. - For example, *.bar.com would match a.bar.com and b.bar.com, but it - would not match a.x.bar.com nor would it match bar.com. If more - than one identity of a given type is present in the certificate - (e.g. more than one dNSName name), a match in any one of the set is - considered acceptable. + For example, *.bar.com would match a.bar.com and b.bar.com, but + it would not match a.x.bar.com nor would it match bar.com. If + more than one identity of a given type is present in the + certificate (e.g. more than one dNSName name), a match in any + one of the set is considered acceptable. If the hostname does not match the dNSName-based identity in the certificate per the above check, user-oriented clients SHOULD either - notify the user (clients MAY give the user the opportunity to + notify the user (clients may give the user the opportunity to continue with the connection in any case) or terminate the + +Harrison Expires April 2004 [Page 10] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + connection and indicate that the server's identity is suspect. Automated clients SHOULD close the connection, returning and/or logging an error indicating that the server's identity is suspect. @@ -524,30 +595,25 @@ Harrison Expires September 2003 [Page 8] Beyond the server identity checks described in this section, clients SHOULD be prepared to do further checking to ensure that the server is authorized to provide the service it is observed to provide. The - client MAY need to make use of local policy information. - - -Harrison Expires September 2003 [Page 9] - - Authentication Methods for LDAPv3 + client may need to make use of local policy information in making + this determination. -5.1.7. Refresh of Server Capabilities Information +4.1.6. Refresh of Server Capabilities Information - Upon TLS session establishment, the client MUST discard all - information about the server fetched prior to the initiation of the - TLS negotiation and MUST refresh any cached server capabilities - information (e.g. from the server's root DSE; see section 3.4 of - [Protocol]). This is necessary to protect against active- - intermediary attacks that may have altered any server capabilities - information retrieved prior to TLS establishment. + Upon TLS session establishment, the client SHOULD discard or refresh + all information about the server fetched prior to the initiation of + the TLS negotiation and not obtained through secure mechanisms. This + protects against active-intermediary attacks that may have altered + any server capabilities information retrieved prior to TLS + establishment. - The server MAY advertise different capabilities after TLS + The server may advertise different capabilities after TLS establishment. In particular, the value of supportedSASLMechanisms - MAY be different after TLS has been negotiated (specifically, the - EXTERNAL mechanism or the proposed PLAIN mechanism are likely to - only be listed after a TLS negotiation has been performed). + may be different after TLS has been negotiated (specifically, the + EXTERNAL and [PLAIN] mechanisms are likely to be listed only after a + TLS negotiation has been performed). -5.2. Effects of TLS on a Client's Authorization Identity +4.2. Effects of TLS on a Client's Authorization Identity This section describes the effects on a client's authorization identity brought about by establishing TLS on an LDAP association. @@ -559,56 +625,60 @@ Harrison Expires September 2003 [Page 9] Authorization identities and related concepts are described in Appendix B. -5.2.1. Default Effects +4.2.1. Default Effects Upon establishment of the TLS session onto the LDAP association, any previously established authentication and authorization identities MUST remain in force, including anonymous state. This holds even in the case where the server requests client authentication via TLS -- e.g. requests the client to supply its certificate during TLS - negotiation (see [RFC2246]). + negotiation. -5.2.2. Client Assertion of Authorization Identity +4.2.2. Client Assertion of Authorization Identity - A client MAY either implicitly request that its LDAP authorization - identity be derived from its authenticated TLS credentials or it MAY - explicitly provide an authorization identity and assert that it be - used in combination with its authenticated TLS credentials. The - former is known as an implicit assertion, and the latter as an - explicit assertion. + The client MAY, upon receipt of a Start TLS response indicating + success, assert that a specific authorization identity be utilized + in determining the client's authorization status. The client + accomplishes this via an LDAP Bind request specifying a SASL + mechanism of "EXTERNAL" [SASL]. A client may either implicitly + request that its LDAP authorization identity be derived from its + +Harrison Expires April 2004 [Page 11] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + + authenticated TLS credentials or it may explicitly provide an + authorization identity and assert that it be used in combination + with its authenticated TLS credentials. The former is known as an + implicit assertion, and the latter as an explicit assertion. -5.2.2.1. Implicit Assertion +4.2.2.1. Implicit Assertion An implicit authorization identity assertion is accomplished after TLS establishment by invoking a Bind request of the SASL form using - the "EXTERNAL" mechanism name [RFC2222] [Protocol] that SHALL NOT + the "EXTERNAL" mechanism name [SASL] [Protocol] that SHALL NOT include the optional credentials octet string (found within the SaslCredentials sequence in the Bind Request). The server will derive the client's authorization identity from the authentication - -Harrison Expires September 2003 [Page 10] - - Authentication Methods for LDAPv3 - identity supplied in the client's TLS credentials (typically a public key certificate) according to local policy. The underlying mechanics of how this is accomplished are implementation specific. -5.2.2.2. Explicit Assertion +4.2.2.2. Explicit Assertion An explicit authorization identity assertion is accomplished after TLS establishment by invoking a Bind request of the SASL form using - the "EXTERNAL" mechanism name [RFC2222] [Protocol] that SHALL - include the credentials octet string. This string MUST be - constructed as documented in section 4.4.1. + the "EXTERNAL" mechanism name [SASL] [Protocol] that SHALL include + the credentials octet string. This string MUST be constructed as + documented in section 3.4.1. -5.2.2.3. Error Conditions + The server MUST verify that the client's authentication identity as + supplied in its TLS credentials is permitted to be mapped to the + asserted authorization identity. The server MUST reject the Bind + operation with an invalidCredentials resultCode in the Bind response + if the client is not so authorized. - For either form of assertion, the server MUST verify that the - client's authentication identity as supplied in its TLS credentials - is permitted to be mapped to the asserted authorization identity. - The server MUST reject the Bind operation with an invalidCredentials - resultCode in the Bind response if the client is not so authorized. +4.2.2.3. Error Conditions Additionally, with either form of assertion, if a TLS session has not been established between the client and server prior to making @@ -616,7 +686,7 @@ Harrison Expires September 2003 [Page 10] of authentication credentials (e.g. IP-level security [RFC2401]), or if during the process of establishing the TLS session, the server did not request the client's authentication credentials, the SASL - EXTERNAL bind MUST fail with a result code of + EXTERNAL bind MUST fail with a resultCode of inappropriateAuthentication. After the above Bind operation failures, any client authentication @@ -627,14 +697,19 @@ Harrison Expires September 2003 [Page 10] close_notify message, based on the Bind failure (as it MAY at any time). -5.2.3. TLS Connection Closure Effects +4.2.3. TLS Connection Closure Effects Closure of the TLS session MUST cause the LDAP association to move to an anonymous authentication and authorization state regardless of + +Harrison Expires April 2004 [Page 12] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + the state established over TLS and regardless of the authentication and authorization state prior to TLS session establishment. -6. LDAP Association State Transition Tables +5. LDAP Association State Transition Tables To comprehensively diagram the various authentication and TLS states through which an LDAP association may pass, this section provides a @@ -642,22 +717,20 @@ Harrison Expires September 2003 [Page 10] states through which an LDAP association may pass during the course of its existence and the actions that cause these changes in state. -6.1. LDAP Association States +5.1. LDAP Association States - -Harrison Expires September 2003 [Page 11] - - Authentication Methods for LDAPv3 - The following table lists the valid LDAP association states and provides a description of each state. The ID for each state is used - in the state transition table in section 6.4. + in the state transition table in section 5.4. ID State Description -- -------------------------------------------------------------- - S1 no Auth ID - no AuthZ ID - [TLS: no Creds, OFF] + S1 Anonymous + no Authentication ID is associated with the LDAP connection + no Authorization ID is in force + No security layer is in effect. + No TLS credentials have been provided + TLS: no Creds, OFF] S2 no Auth ID no AuthZ ID [TLS: no Creds, ON] @@ -680,11 +753,17 @@ Harrison Expires September 2003 [Page 11] AuthZ ID= K [TLS: Creds Auth ID "I", ON] -6.2. Actions that Affect LDAP Association State +5.2. Actions that Affect LDAP Association State The following table lists the actions that can affect the state of an LDAP association. The ID for each action is used in the state - transition table in section 6.4. + transition table in section 5.4. + + +Harrison Expires April 2004 [Page 13] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + ID Action -- ------------------------------------------------ @@ -700,24 +779,20 @@ Harrison Expires September 2003 [Page 11] A5 Client or Server: send TLS closure alert ([Protocol] section X) A6 Client: Bind w/simple password or SASL mechanism (e.g. DIGEST- - MD5 password, Kerberos, etc. -รป except EXTERNAL [Auth ID "X" - -Harrison Expires September 2003 [Page 12] - - Authentication Methods for LDAPv3 - + MD5 password, Kerberos, etc., except EXTERNAL [Auth ID "X" maps to AuthZ ID "Y"] A7 Client Binds SASL EXTERNAL with credentials: AuthZ ID "J" - [Explicit Assertion (section 5.2.1.2.2)] + [Explicit Assertion (section 4.2.1.2.2)] A8 Client Bind SASL EXTERNAL without credentials [Implicit - Assertion (section 5.2 .1.2.1)] + Assertion (section 4.2.1.2.1)] + A9 Client abandons a bind operation or bind operation fails -6.3. Decisions Used in Making LDAP Association State Changes +5.3. Decisions Used in Making LDAP Association State Changes Certain changes in the state of an LDAP association are only allowed if the server can affirmatively answer a question. These questions are applied as part of the criteria for allowing or disallowing a - state change in the state transition table in section 6.4. + state change in the state transition table in section 5.4. ID Decision Question -- -------------------------------------------------------------- @@ -725,7 +800,7 @@ Harrison Expires September 2003 [Page 12] D2 Can a valid AuthZ ID "K" be derived from TLS Credentials Auth ID "I"? -6.4. LDAP Association State Transition Table +5.4. LDAP Association State Transition Table The LDAP Association table below lists the valid states for an LDAP association and the actions that could affect them. For any given @@ -742,6 +817,11 @@ Harrison Expires September 2003 [Page 12] State Action State Comment ------- ------------- ----- ----------------------------------- S1 A1 S1 + +Harrison Expires April 2004 [Page 14] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + S1 A2 S1 Error: Inappropriate authentication S1 A3 S2 S1 A4 S3 @@ -759,11 +839,6 @@ Harrison Expires September 2003 [Page 12] S2 A7 ? identity could be provided by another underlying mechanism such as IPSec. - -Harrison Expires September 2003 [Page 13] - - Authentication Methods for LDAPv3 - S2 A8 ? identity could be provided by another underlying mechanism such as IPSec. @@ -776,7 +851,7 @@ Harrison Expires September 2003 [Page 13] S3 A8 and D2=NO S3 Error: InvalidCredentials S3 A8 and D2=YES S8 S4 A1 S1 - S4 A2 S4 Error: Inappropriate Authentication + S4 A2 S1 Error: Inappropriate Authentication S4 A3 S5 S4 A4 S6 S4 A5 S1 @@ -788,7 +863,7 @@ Harrison Expires September 2003 [Page 13] another underlying mechanism such as IPSec. S5 A1 S2 - S5 A2 S5 Error: Inappropriate Authentication + S5 A2 S2 Error: Inappropriate Authentication S5 A5 S1 S5 A6 S5 S5 A7 ? identity could be provided by @@ -798,35 +873,36 @@ Harrison Expires September 2003 [Page 13] another underlying mechanism such as IPSec. S6 A1 S3 - S6 A2 S6 Error: Inappropriate Authentication + S6 A2 S2 Error: Inappropriate Authentication + +Harrison Expires April 2004 [Page 15] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + S6 A5 S1 S6 A6 S6 S6 A7 and D1=NO S6 Error: InvalidCredentials S6 A7 and D1=YES S7 - S6 A8 and D2=NO S6 Error: InvalidCredentials + S6 A8 and D2=NO S3 Error: InvalidCredentials S6 A8 and D2=YES S8 S7 A1 S3 - S7 A2 S7 Error: Inappropriate Authentication + S7 A2 S2 Error: Inappropriate Authentication S7 A5 S1 S7 A6 S6 S7 A7 S7 S7 A8 and D2=NO S3 Error: InvalidCredentials S7 A8 and D2=YES S8 S8 A1 S3 - S8 A2 S8 Error: Inappropriate Authentication + S8 A2 S2 Error: Inappropriate Authentication S8 A5 S1 S8 A6 S6 - -Harrison Expires September 2003 [Page 14] - - Authentication Methods for LDAPv3 - S8 A7 and D1=NO S6 Error: InvalidCredentials S8 A7 and D1=YES S7 S8 A8 S8 + Any A9 S1 See [Protocol] section 4.2.1. -7. Anonymous Authentication +6. Anonymous Authentication Directory operations that modify entries or access protected attributes or entries generally require client authentication. @@ -836,10 +912,10 @@ Harrison Expires September 2003 [Page 14] access sensitive information in directory entries. LDAP implementations MUST support anonymous authentication, as - defined in section 7.1. + defined in section 6.1. LDAP implementations MAY support anonymous authentication with TLS, - as defined in section 7.2. + as defined in section 6.2. While there MAY be access control restrictions to prevent access to directory entries, an LDAP server SHOULD allow an anonymously-bound @@ -850,132 +926,136 @@ Harrison Expires September 2003 [Page 14] by the lower layers or external means to grant or deny access even to anonymously authenticated clients. -7.1. Anonymous Authentication Procedure +6.1. Anonymous Authentication Procedure - An LDAPv3 client that has not successfully completed a bind - operation on a connection is anonymously authenticated. See section - 4.3.3. + Prior to successfully completing a Bind operation, the LDAP + association is anonymous. See section 3.1. + + + +Harrison Expires April 2004 [Page 16] + +Internet-Draft LDAP Authentication Methods 7 October 2003 - An LDAP client MAY also choose to explicitly bind anonymously. A - client that wishes to do so MUST choose the simple authentication - option in the Bind Request (see section 4.1) and set the password to - be of zero length. (This is often done by LDAPv2 clients.) Typically - the name is also of zero length. + An LDAP client may also explicitly establish an anonymous + association. A client that wishes to do so MUST choose the simple + authentication option in the Bind Request and set the password to be + of zero length. (This is often done by LDAPv2 clients.) Typically + the name is also of zero length. A bind request where both the name + and password are of zero length is said to be an anonymous bind. A + bind request where the name, a DN, is of non-zero length, and the + password is of zero length is said to be an unauthenticated bind. + Both variations produce an anonymous association. -7.2. Anonymous Authentication and TLS +6.2. Anonymous Authentication and TLS An LDAP client MAY use the Start TLS operation (section 5) to - negotiate the use of TLS security [RFC2246]. If the client has not - bound beforehand, then until the client uses the EXTERNAL SASL - mechanism to negotiate the recognition of the client's certificate, - the client is anonymously authenticated. + negotiate the use of [TLS] security. If the client has not bound + beforehand, then until the client uses the EXTERNAL SASL mechanism + to negotiate the recognition of the client's certificate, the client + is anonymously authenticated. - Recommendations on TLS ciphersuites are given in section 10. + Recommendations on TLS ciphersuites are given in section 9. An LDAP server which requests that clients provide their certificate during TLS negotiation MAY use a local security policy to determine - - -Harrison Expires September 2003 [Page 15] - - Authentication Methods for LDAPv3 - whether to successfully complete TLS negotiation if the client did not present a certificate which could be validated. -8. Password-based Authentication +7. Password-based Authentication This section discusses various options for performing password-based - authentication to LDAPv3 compliant servers and the environments + authentication to LDAP compliant servers and the environments suitable for their use. -8.1. Simple Authentication +7.1. Simple Authentication The LDAP "simple" authentication choice is not suitable for authentication in environments where there is no network or transport layer confidentiality. LDAP implementations SHOULD support authentication with the "simple" authentication choice when the connection is protected against eavesdropping using TLS, as defined - in section 5. LDAP implementations SHOULD NOT support authentication + in section 4. LDAP implementations SHOULD NOT support authentication with the "simple" authentication choice unless the data on the connection is protected using TLS or other data confidentiality and data integrity protection. -8.2. Digest Authentication - - LDAP servers that implement any password-based authentication method - MUST support authentication with a password using the DIGEST-MD5 - SASL mechanism for password protection. - - An LDAP client MAY determine whether the server supports this - mechanism by performing a search request on the root DSE, requesting - the supportedSASLMechanisms attribute, and checking whether the - string "DIGEST-MD5" is present as a value of this attribute. - - In the first stage of authentication, when the client is performing - an "initial authentication" as defined in section 2.1 of [RFC2831], - the client sends a bind request in which the version number is 3, - the authentication choice is sasl, the sasl mechanism name is - "DIGEST-MD5", and the credentials are absent. The client then waits - for a response from the server to this request. - - The server will respond with a bind response in which the resultCode - is saslBindInProgress, and the serverSaslCreds field is present. The - contents of this field is a string defined by "digest-challenge" in - section 2.1.1 of [RFC2831]. The server SHOULD include a realm - indication and MUST indicate support for UTF-8. - - The client will send a bind request with a distinct message id, in - which the version number is 3, the authentication choice is sasl, - the sasl mechanism name is "DIGEST-MD5", and the credentials contain - the string defined by "digest-response" in section 2.1.2 of - [RFC2831]. The serv-type is "ldap". - - The server will respond with a bind response in which the resultCode - is either success, or an error indication. If the authentication is - successful and the server does not support subsequent - -Harrison Expires September 2003 [Page 16] - - Authentication Methods for LDAPv3 - - authentication, then the credentials field is absent. If the - authentication is successful and the server supports subsequent - authentication, then the credentials field contains the string - defined by "response-auth" in section 2.1.3 of [RFC2831]. Support - for subsequent authentication is OPTIONAL in clients and servers. +7.2. Digest Authentication + + LDAP servers that implement any authentication method or mechanism + (other than simple anonymous bind) MUST implement the SASL + DIGEST-MD5 mechanism [DigestAuth]. + + Support for subsequent authentication is OPTIONAL in clients and + servers. + + + -8.3. "simple" authentication choice under TLS encryption +Harrison Expires April 2004 [Page 17] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + + Implementors must take care to ensure that they maintain the + semantics of the DIGEST-MD5 specification even when handling data + that has different semantics in the LDAP protocol. + For example, the SASL DIGEST-MD5 authentication mechanism utilizes + realm and username values ([DigestAuth section 2.1) which are + syntactically simple strings and semsantically simple realm and + username values. These values are not LDAP DNs, and there is no + requirement that they be represented or treated as such. Username + and realm values that look like LDAP DNs in form, e.g. "cn=bob, + o=Ace Industry ", are syntactically allowed, however DIGEST-MD5 + treats them as simple strings for comparison purposes. To illustrate + further, the two DNs "cn=bob, o=Ace Industry" (space between RDNs) + and "cn=bob,o=Ace Industry" (no space between RDNs) would be + equivalent when being compared semantically as LDAP DNs, however + they are not equivalent if they were used to represent username + values in DIGEST-MD5 because simple octet-wise comparision semantics + are used by DIGEST-MD5. + + +7.3. "simple" authentication choice under TLS encryption Following the negotiation of an appropriate TLS ciphersuite - providing connection confidentiality [RFC2246], a client MAY - authenticate to a directory that supports the simple authentication - choice by performing a simple bind operation. + providing connection confidentiality, a client MAY authenticate to a + directory that supports the simple authentication choice by + performing a simple bind operation - The client will use the Start TLS operation [Protocol] to negotiate - the use of TLS security [RFC2246] on the connection to the LDAP - server. The client need not have bound to the directory beforehand. + Simple authentication with TLS encryption protection is performed as + follows: - For this authentication procedure to be successful, the client and - server MUST negotiate a ciphersuite which contains a bulk encryption - algorithm of appropriate strength. Recommendations on cipher suites - are given in section 10. + 1. The client will use the Start TLS operation [Protocol] to + negotiate the use of TLS security [TLS] on the connection to + the LDAP server. The client need not have bound to the + directory beforehand. + + For the subsequent authentication procedure to be performed + securely, the client and server MUST negotiate a ciphersuite + which contains a bulk encryption algorithm of appropriate + strength. Recommendations on cipher suites are given in + section 9. - Following the successful completion of TLS negotiation, the client - MUST send an LDAP bind request with the version number of 3, the - name field containing a DN, and the "simple" authentication choice, - containing a password. + 2. Following the successful completion of TLS negotiation, the + client MUST send an LDAP bind request with the version number + of 3, the name field containing a DN, and the "simple" + authentication choice, containing a password. -8.3.1. "simple" Authentication Choice +7.3.1. "simple" Authentication Choice DSAs that map the DN sent in the bind request to a directory entry with an associated set of one or more passwords will compare the presented password to the set of passwords associated with that - entry. If there is a match, then the server will respond with - resultCode success, otherwise the server will respond with - resultCode invalidCredentials. + entry. If the presented password matches any member of that set, + then the server will respond with a success resultCode, otherwise + the server will respond with an invalidCredentials resultCode. -8.4. Other authentication choices with TLS + +Harrison Expires April 2004 [Page 18] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + +7.4. Other authentication choices with TLS It is also possible, following the negotiation of TLS, to perform a SASL authentication that does not involve the exchange of plaintext @@ -983,21 +1063,16 @@ Harrison Expires September 2003 [Page 16] negotiate a ciphersuite that provides confidentiality if the only service required is data integrity. -9. Certificate-based authentication +8. Certificate-based authentication LDAP server implementations SHOULD support authentication via a - client certificate in TLS, as defined in section 5.2.2. + client certificate in TLS, as defined in section 8.1. -9.1. Certificate-based authentication with TLS +8.1. Certificate-based authentication with TLS A user who has a public/private key pair in which the public key has been signed by a Certification Authority may use this key pair to authenticate to the directory server if the user's certificate is - -Harrison Expires September 2003 [Page 17] - - Authentication Methods for LDAPv3 - requested by the server. The user's certificate subject field SHOULD be the name of the user's directory entry, and the Certification Authority that issued the user's certificate must be sufficiently @@ -1011,8 +1086,8 @@ Harrison Expires September 2003 [Page 17] configured to support certificates for which no mapping is required. The client will use the Start TLS operation [Protocol] to negotiate - the use of TLS security [RFC2246] on the connection to the LDAP - server. The client need not have bound to the directory beforehand. + the use of TLS security [TLS] on the connection to the LDAP server. + The client need not have bound to the directory beforehand. In the TLS negotiation, the server MUST request a certificate. The client will provide its certificate to the server, and the server @@ -1022,7 +1097,7 @@ Harrison Expires September 2003 [Page 17] In deployments that require protection of sensitive data in transit, the client and server MUST negotiate a ciphersuite that contains a bulk encryption algorithm of appropriate strength. Recommendations - of cipher suites are given in section 10. + of cipher suites are given in section 9. The server MUST verify that the client's certificate is valid. The server will normally check that the certificate is issued by a known @@ -1033,31 +1108,71 @@ Harrison Expires September 2003 [Page 17] Following the successful completion of TLS negotiation, the client will send an LDAP bind request with the SASL "EXTERNAL" mechanism. -10. TLS Ciphersuites +9. TLS Ciphersuites + +Harrison Expires April 2004 [Page 19] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + - The following ciphersuites defined in [RFC2246] MUST NOT be used for + A client or server that supports TLS MUST support + TLS_DHE_DSS_WITH_3DES_EDE_CBC_SHA and MAY support other ciphersuites + offering equivalent or better protection. + + Several issues should be considered when selecting TLS ciphersuites + that are appropriate for use in a given circumstance. These issues + include the following: + + - The ciphersuite's ability to provide adequate confidentiality + protection for passwords and other data sent over the LDAP + connection. Client and server implementers should recognize that + some TLS ciphersuites provide no confidentiality protection + while other ciphersuites that do provide confidentiality + protection may be vulnerable to being cracked using brute force + methods, especially in light of ever-increasing CPU speeds that + reduce the time needed to successfully mount such attacks. + + Client and server implementers SHOULD carefully consider the + value of the password or data being protected versus the level + of confidentially protection provided by the ciphersuite to + ensure that the level of protection afforded by the ciphersuite + is appropriate. + + - The ciphersuite's vulnerability (or lack thereof) to man-in-the- + middle attacks. Ciphersuites vulnerable to man-in-the-middle + attacks SHOULD NOT be used to protect passwords or sensitive + data, unless the network configuration is such that the danger + of a man-in-the-middle attack is tolerable. + +9.1. TLS Ciphersuites Recommendations + + As of the writing of this document, the following recommendations + regarding TLS ciphersuites are applicable. Because circumstances are + constantly changing, this list must not be considered exhaustive, + but is hoped that it will serve as a useful starting point for + implementers. + + The following ciphersuites defined in [TLS] MUST NOT be used for confidentiality protection of passwords or data: TLS_NULL_WITH_NULL_NULL TLS_RSA_WITH_NULL_MD5 TLS_RSA_WITH_NULL_SHA - The following ciphersuites defined in [RFC2246] can be cracked - easily (less than a day of CPU time on a standard CPU in 2000). - These ciphersuites are NOT RECOMMENDED for use in confidentiality - protection of passwords or data. Client and server implementers - SHOULD carefully consider the value of the password or data being - protected before using these ciphersuites: + The following ciphersuites defined in [TLS] can be cracked easily + (less than a day of CPU time on a standard CPU in 2000) and are NOT + RECOMMENDED for use in confidentiality protection of passwords or + data. TLS_RSA_EXPORT_WITH_RC4_40_MD5 TLS_RSA_EXPORT_WITH_RC2_CBC_40_MD5 TLS_RSA_EXPORT_WITH_DES40_CBC_SHA + TLS_DH_DSS_EXPORT_WITH_DES40_CBC_SHA -Harrison Expires September 2003 [Page 18] +Harrison Expires April 2004 [Page 20] - Authentication Methods for LDAPv3 +Internet-Draft LDAP Authentication Methods 7 October 2003 - TLS_DH_DSS_EXPORT_WITH_DES40_CBC_SHA TLS_DH_RSA_EXPORT_WITH_DES40_CBC_SHA TLS_DHE_DSS_EXPORT_WITH_DES40_CBC_SHA TLS_DHE_RSA_EXPORT_WITH_DES40_CBC_SHA @@ -1065,9 +1180,7 @@ Harrison Expires September 2003 [Page 18] TLS_DH_anon_EXPORT_WITH_DES40_CBC_SHA The following ciphersuites are vulnerable to man-in-the-middle - attacks, and SHOULD NOT be used to protect passwords or sensitive - data, unless the network configuration is such that the danger of a - man-in-the-middle attack is tolerable: + attacks: TLS_DH_anon_EXPORT_WITH_RC4_40_MD5 TLS_DH_anon_WITH_RC4_128_MD5 @@ -1075,47 +1188,58 @@ Harrison Expires September 2003 [Page 18] TLS_DH_anon_WITH_DES_CBC_SHA TLS_DH_anon_WITH_3DES_EDE_CBC_SHA - A client or server that supports TLS MUST support - TLS_DHE_DSS_WITH_3DES_EDE_CBC_SHA and MAY support other ciphersuites - offering equivalent or better protection. + -11. Security Considerations +10. Security Considerations Security issues are discussed throughout this memo; the (unsurprising) conclusion is that mandatory security is important and that session confidentiality protection is required when snooping is a problem. - Servers are encouraged to prevent modifications by anonymous users. + Servers are encouraged to prevent modifications by anonymous users. + Servers may also wish to minimize denial of service attacks by timing out idle connections, and returning the unwillingToPerform - result code rather than performing computationally expensive + resultCode rather than performing computationally expensive operations requested by unauthorized clients. - Operational experience shows that clients can misuse unauthenticated - access (simple bind with name but no password). For this reason, - servers SHOULD by default reject authentication requests that have a - DN with an empty password with an error of invalidCredentials. + The use of cleartext passwords is strongly discouraged over open + networks when the underlying transport service cannot guarantee + confidentiality. - Access control SHOULD be applied when reading sensitive information - or updating directory information. + Operational experience shows that clients can misuse unauthenticated + access (simple bind with name but no password). For example, a + client program might authenticate a user via LDAP and then grant + access to information not stored in the directory on the basis of + completing a successful bind. Some implementations will return a + success response to a simple bind that consists of a user name and + an empty password thus leaving the impression that the client has + successfully authenticated the identity represented by the user + name, when in reality, the directory server has simply performed an + anonymous bind. For this reason, servers SHOULD by default reject + authentication requests that have a DN with an empty password with + an error of invalidCredentials. + + Access control SHOULD always be applied when reading sensitive + information or updating directory information. A connection on which the client has not performed the Start TLS operation or negotiated a suitable SASL mechanism for connection + + +Harrison Expires April 2004 [Page 21] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + integrity and encryption services is subject to man-in-the-middle attacks to view and modify information in transit. -11.1. Start TLS Security Considerations +10.1. Start TLS Security Considerations The goals of using the TLS protocol with LDAP are to ensure connection confidentiality and integrity, and to optionally provide - for authentication. TLS expressly provides these capabilities, as - described in [RFC2246]. - -Harrison Expires September 2003 [Page 19] - - Authentication Methods for LDAPv3 - + for authentication. [TLS] expressly provides these capabilities. All security gained via use of the Start TLS operation is gained by the use of TLS itself. The Start TLS operation, on its own, does not @@ -1154,63 +1278,99 @@ Harrison Expires September 2003 [Page 19] via TLS is required. Additional security considerations relating to the EXTERNAL - mechanism to negotiate TLS can be found in [RFC2222] and [RFC2246]. + mechanism to negotiate TLS can be found in [SASL] and [TLS]. +11. IANA Considerations -12. Acknowledgements + The following IANA considerations apply to this document: + + Please update the GSSAPI service name registry to point to [Roadmap] + and this document. + +Harrison Expires April 2004 [Page 22] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + + [To be completed] + +Contributors + This document combines information originally contained in RFC 2829 - and RFC 2830. The author acknowledges the work of Harald Tveit + and RFC 2830. The editor acknowledges the work of Harald Tveit Alvestrand, Jeff Hodges, Tim Howes, Steve Kille, RL "Bob" Morgan , and Mark Wahl, each of whom authored one or more of these documents. - RFC 2829 and RFC 2830 were products of the IETF LDAPEXT Working - Group. RFC 2251 was a product of the ASID Working Group. +Acknowledgements + This document is based upon input of the IETF LDAP Revision working - group. The contributions of its members is greatly appreciated. + group. The contributions and suggestions made by its members in + shaping the contents and technical accuracy of this document is + greatly appreciated. -13. Normative References - -Harrison Expires September 2003 [Page 20] - - Authentication Methods for LDAPv3 - +Normative References [RFC2119] Bradner, S., "Key Words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. - [RFC2222] Myers, J., "Simple Authentication and Security Layer - (SASL)", draft-myers-saslrev-xx.txt, a work in progress. - [RFC2234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax Specifications: ABNF", RFC 2234, November 1997. - [RFC2246] Dierks, T. and C. Allen. "The TLS Protocol Version 1.0", - RFC 2246, January 1999. - - [RFC2831] Leach, P. and C. Newman, "Using Digest Authentication as - a SASL Mechanism", RFC 2831, May 2000. + [DigestAuth] Leach, P. C. Newman, and A. Melnikov, "Using Digest + Authentication as a SASL Mechanism", draft-ietf-sasl-rfc2831bis- + xx.txt, a work in progress. [LDAPDN] Zeilenga, Kurt D. (editor), "LDAP: String Representation of Distinguished Names", draft-ietf-ldapbis-dn-xx.txt, a work in progress. + [Model] Zeilenga, Kurt D. (editor), "LDAP: Directory Information + Models", draft-ietf-ldapbis-models-xx.txt, a work in progress. + [Protocol] Sermersheim, J., "LDAP: The Protocol", draft-ietf- ldapbis-protocol-xx.txt, a work in progress. - [ROADMAP] K. Zeilenga, "LDAP: Technical Specification Road Map", + [Roadmap] K. Zeilenga, "LDAP: Technical Specification Road Map", draft-ietf-ldapbis-roadmap-xx.txt, a work in progress. - -14. Informative References + + [SASL] Melnikov, A. (editor), "Simple Authentication and Security + Layer (SASL)", draft-ietf-sasl-rfc2222bis-xx.txt, a work in + progress. + + [Syntaxes] Legg, S. (editor), "LDAP: Syntaxes and Matching Rules", + draft-ietf-ldapbis-syntaxes-xx.txt, a work in progress. + + [TLS] Dierks, T. and C. Allen. "The TLS Protocol Version 1.1", + draft-ietf-tls-rfc2246-bis-xx.txt, a work in progress. + + [UTF-8] Yergeau, F., "UTF-8, a transformation format of ISO 10646", + RFC 2279, January 1998. + +Harrison Expires April 2004 [Page 23] + +Internet-Draft LDAP Authentication Methods 7 October 2003 - [RFC2828] Shirey, R., "Internet Security Glossary", RFC 2828, May + + [Unicode] International Organization for Standardization, "Universal + Multiple-Octet Coded Character Set (UCS) - Architecture and + Basic Multilingual Plane", ISO/IEC 10646-1 : 1993. + +Informative References + + [ANONYMOUS] Zeilenga, K.,"Anonymous SASL Mechanism", draft-zeilenga- + sasl-anon-xx.txt, a work in progress. + + [PLAIN] Zeilenga, K.,"Plain SASL Mechanism", draft-zeilenga-sasl- + plain-xx.txt, a work in progress. + + [RFC2828] Shirey, R., "Internet Security Glossary", RFC 2828, May 2000. [RFC2401] Kent, S. and R. Atkinson, "Security Architecture for the Internet Protocol", RFC 2401, November 1998. -15. Author's Address +Author's Address Roger Harrison Novell, Inc. @@ -1219,9 +1379,9 @@ Harrison Expires September 2003 [Page 20] +1 801 861 2642 roger_harrison@novell.com -16. Full Copyright Statement +Full Copyright Statement - Copyright (C) The Internet Society (2000). All Rights Reserved. + Copyright (C) The Internet Society (2003). All Rights Reserved. This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it @@ -1229,11 +1389,6 @@ Harrison Expires September 2003 [Page 20] and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this - -Harrison Expires September 2003 [Page 21] - - Authentication Methods for LDAPv3 - document itself may not be modified in any way, such as by removing the copyright notice or references to the Internet Society or other Internet organizations, except as needed for the purpose of @@ -1249,6 +1404,11 @@ Harrison Expires September 2003 [Page 21] "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION + +Harrison Expires April 2004 [Page 24] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. @@ -1288,11 +1448,6 @@ Appendix A. Example Deployment Scenarios sensitive authentication information AND data integrity for all authentication information. - -Harrison Expires September 2003 [Page 22] - - Authentication Methods for LDAPv3 - (5) A directory containing sensitive data. This scenario requires data confidentiality protection AND secure authentication. @@ -1308,11 +1463,16 @@ B.1. Access Control Policy An access control policy is a set of rules defining the protection of resources, generally in terms of the capabilities of persons or other entities accessing those resources. A common expression of an + +Harrison Expires April 2004 [Page 25] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + access control policy is an access control list. Security objects and mechanisms, such as those described here, enable the expression of access control policies and their enforcement. Access control - policies are typically expressed in terms of access control - attributes as described below. + policies are typically expressed in terms of access control factors + as described below. B.2. Access Control Factors @@ -1348,11 +1508,6 @@ B.3. Authentication, Credentials, Identity mechanism may constrain the form of authentication identities used with it. -Harrison Expires September 2003 [Page 23] - - Authentication Methods for LDAPv3 - - B.4. Authorization Identity An authorization identity is one kind of access control factor. It @@ -1367,13 +1522,18 @@ B.4. Authorization Identity identity distinct from the authentication identity asserted by the client's credentials. This permits agents such as proxy servers to authenticate using their own credentials, yet request the access - privileges of the identity for which they are proxying [RFC2222]. - Also, the form of authentication identity supplied by a service like - TLS may not correspond to the authorization identities used to - express a server's access control policy, requiring a server- - specific mapping to be done. The method by which a server composes - and validates an authorization identity from the authentication - credentials supplied by a client is implementation-specific. + +Harrison Expires April 2004 [Page 26] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + + privileges of the identity for which they are proxying [SASL]. Also, + the form of authentication identity supplied by a service like TLS + may not correspond to the authorization identities used to express a + server's access control policy, requiring a server-specific mapping + to be done. The method by which a server composes and validates an + authorization identity from the authentication credentials supplied + by a client is implementation-specific. Appendix C. RFC 2829 Change History @@ -1383,9 +1543,9 @@ Appendix C. RFC 2829 Change History C.0. General Editorial Changes Version -00 - - Changed other instances of the term LDAP to LDAPv3 where v3 of - the protocol is implied. Also made all references to LDAPv3 use - the same wording. + - Changed other instances of the term LDAP to LDAP where v3 of the + protocol is implied. Also made all references to LDAP use the + same wording. - Miscellaneous grammatical changes to improve readability. @@ -1406,11 +1566,6 @@ C.2. Changes to Section 2 Version -01 - -Harrison Expires September 2003 [Page 24] - - Authentication Methods for LDAPv3 - - Moved section to an appendix. C.3. Changes to Section 3 @@ -1426,6 +1581,11 @@ C.4 Changes to Section 4 - Changed "Distinguished Name" to "LDAP distinguished name". C.5. Changes to Section 5 + +Harrison Expires April 2004 [Page 27] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + Version -00 @@ -1464,14 +1624,8 @@ C.6. Changes to Section 6. authentication unless confidentiality and data integrity mechanisms are in force. - - -Harrison Expires September 2003 [Page 25] - - Authentication Methods for LDAPv3 - 2. Moved first paragraph of section 6 (beginning with "LDAP - implementations MUST support authentication with a passwordร ") + implementations MUST support authentication with a password...") to section on Digest Authentication (Now section 6.2). C.6.1. Changes to Section 6.1. @@ -1479,13 +1633,18 @@ C.6.1. Changes to Section 6.1. Version -00 Renamed section to 6.2 - Added sentence from original section 6 indicating that the - DIGEST-MD5 SASL mechanism is required for all conforming LDAPv3 + DIGEST-MD5 SASL mechanism is required for all conforming LDAP implementations C.6.2. Changes to Section 6.2 Version -00 + +Harrison Expires April 2004 [Page 28] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + - Renamed section to 6.3 - Reworded first paragraph to remove reference to user and the @@ -1524,11 +1683,6 @@ C.7.1. Changes to section 7.1. C.8. Changes to section 8. - -Harrison Expires September 2003 [Page 26] - - Authentication Methods for LDAPv3 - Version -00 - Removed the first paragraph because simple authentication is @@ -1546,6 +1700,11 @@ Harrison Expires September 2003 [Page 26] for Other Security Services) to bring material on SASL mechanisms together into one location. +Harrison Expires April 2004 [Page 29] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + + C.9. Changes to section 9. Version -00 @@ -1582,12 +1741,6 @@ C.10. Changes to Section 10. and server implementers SHOULD" to sentence just prior the second list of ciphersuites. - - -Harrison Expires September 2003 [Page 27] - - Authentication Methods for LDAPv3 - - Added text: "and MAY support other ciphersuites offering equivalent or better protection," to the last paragraph of the section. @@ -1605,6 +1758,11 @@ C.12. Changes to Section 12. - Inserted new section 12 that specifies when SASL protections begin following SASL negotiation, etc. The original section 12 is renumbered to become section 13. + +Harrison Expires April 2004 [Page 30] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + Version -01 @@ -1642,11 +1800,6 @@ E.0. General Editorial Changes - All material from section 4.2 of RFC 2251 was moved into this document. - -Harrison Expires September 2003 [Page 28] - - Authentication Methods for LDAPv3 - - A new section was created for the Bind Request - Section 4.2.1 of RFC 2251 (Sequencing Bind Request) was moved @@ -1664,11 +1817,16 @@ Appendix F. Change History to Combined Document F.1. Changes for draft-ldap-bis-authmeth-02 General + +Harrison Expires April 2004 [Page 31] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + - Added references to other LDAP standard documents, to sections within the document, and fixed broken references. - - General editorial changesรนpunctuation, spelling, formatting, + - General editorial changes--punctuation, spelling, formatting, etc. Section 1. @@ -1701,11 +1859,6 @@ F.1. Changes for draft-ldap-bis-authmeth-02 statement and one that prohibited use of ANONYMOUS and PLAIN SASL mechanisms.) - -Harrison Expires September 2003 [Page 29] - - Authentication Methods for LDAPv3 - Section 5.3.6 - Added a.x.bar.com to wildcard matching example on hostname @@ -1723,6 +1876,11 @@ Harrison Expires September 2003 [Page 29] - Brought security terminology in line with IETF security glossary throughout the appendix. + +Harrison Expires April 2004 [Page 32] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + F.2. Changes for draft-ldap-bis-authmeth-03 General @@ -1760,11 +1918,6 @@ F.2. Changes for draft-ldap-bis-authmeth-03 - Generalized the language of this section to not refer to any specific password attribute or to refer to the directory entry as a "user" entry. - -Harrison Expires September 2003 [Page 30] - - Authentication Methods for LDAPv3 - Section 11 @@ -1781,6 +1934,12 @@ F.3. Changes for draft-ldap-bis-authmeth-04 General + + +Harrison Expires April 2004 [Page 33] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + - Changed references to use [RFCnnnn] format wherever possible. (References to works in progress still use [name] format.) - Various edits to correct typos and bring field names, etc. in @@ -1819,11 +1978,6 @@ F.3. Changes for draft-ldap-bis-authmeth-04 - Section 13 - -Harrison Expires September 2003 [Page 31] - - Authentication Methods for LDAPv3 - - Verified all normative references and moved informative references to a new section 14. @@ -1839,14 +1993,20 @@ F.4. Changes for draft-ldap-bis-authmeth-05 several changes to correct improper usage. Abstract + + +Harrison Expires April 2004 [Page 34] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + - Updated to match current contents of documents. This was needed due to movement of material on Bind and Start TLS operations to [Protocol] in this revision. Section 3. - - Renamed section to "Rationale for LDAPv3 Security Mechanisms" - and removed text that did not support this theme. Part of the + - Renamed section to "Rationale for LDAP Security Mechanisms" and + removed text that did not support this theme. Part of the motivation for this change was to remove the implication of the previous section title, "Required Security Mechanisms", and other text found in the section that everything in the section @@ -1878,11 +2038,6 @@ F.4. Changes for draft-ldap-bis-authmeth-05 mechanisms not explicitly mentioned in this document. Section 4.4.1. - -Harrison Expires September 2003 [Page 32] - - Authentication Methods for LDAPv3 - - Added paragraph beginning, "The dnAuthzID choice allows client applications..." to clarify whether DN form authorization @@ -1898,6 +2053,11 @@ Harrison Expires September 2003 [Page 32] section. Section 5.1.7. + +Harrison Expires April 2004 [Page 35] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + - Wording from section 3 paragraph beginning " If TLS is negotiated, the client MUST discard all information..." was @@ -1935,13 +2095,232 @@ Harrison Expires September 2003 [Page 32] - Began changes to incorporate information on deployment scenarios removed from section 3. + +F.5. Changes for draft-ldap-bis-authmeth-06 + + + General + + - Combined Section 2 (Introduction) and Section 3 (Motivation) and + moved Introduction to section 1. All following sections numbers + were decremented by one as result. + + - Edits to fix typos, I-D nits, etc. + - Opened several new issues in Appendix G based on feedback from + WG. Some of these have been resolved. Others require further + discussion. + + Section 1 +Harrison Expires April 2004 [Page 36] + +Internet-Draft LDAP Authentication Methods 7 October 2003 -Harrison Expires September 2003 [Page 33] + + - Added additional example of spoofing under threat (7). + + Section 2.1 + + - Changed definition of "LDAP association" and added terms, + "connection" and "TLS connection" to bring usage in line with + [Protocol]. + + Section 4.1.6 + + - Clarified sentence stating that the client MUST NOT use derived + forms of DNS names. + + Section 5.1 + + - Began edits to LDAP Association state table to clarify meaning + of various states and actions. + + - Added action A9 to cover abandoned bind operation and added + appropriate transitions to the state transition table to + accommodate it. + + Section 7.2 + + - Replaced first paragraph to clarify that the "DIGEST-MD5" SASL + mechanism is required to implement. + + Section 9 + + - Rewrote the section to make the advice more applicable over the + long term, i.e. more "timeless." The intent of content in the + original section was preserved. + + Section 10 + + - Added a clarifying example to the consideration regarding misuse + of unauthenticated access. + +F.6. Changes for draft-ldap-bis-authmeth-07 + + + General + + - Updated external and internal references to accommodate changes + in recent drafts. + + - Opened several new issues in Appendix G based on feedback from + WG. Some of these have been resolved. Others require further + discussion. + + Section 3 + + + +Harrison Expires April 2004 [Page 37] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + + - Rewrote much of section 3.3 to mee the SASL profile requirements + of draft-ietf-sasl-rfc2222bis-xx.txt section 5. + + - Changed treatement of SASL ANONYMOUS and PLAIN mechanisms to + bring in line with WG consensus. + + Section 4 + + - Note to implementers in section 4.1.1 based on operational + experience. + + - Clarification on client continuing by performing a Start TLS + with TLS already established in section 4.1.4. + + - Moved verification of mapping of client's authentication ID to + asserted authorization ID to apply only to explicit assertion. + The local policy in place for implicit assertion is adequate. + + Section 7 + + - Removed most of section 7.2 as the information is now covered + adequately via the new SASL profile in section 3.3. Added note + to implementors regarding the treatment of username and realm + values in DIGEST-MD5. + + - Section 7.3. Minor clarifications in wording. + + - Section 7.3.1. Clarification that a match of the presented value + to any member of the set of stored passwords constitutes a + successful authentication. + +F.6. Changes for draft-ldap-bis-authmeth-08 + + + General + + - Changed usage from LDAPv3 to LDAP for usage consistency across + LDAP technical specification. + - Fixed a number of usage nits for consistency and to bring doc in + conformance with publication guidelines. + + Abstract + + - Significant cleanup and rewording of abstract based on WG + feedback. + + Section 2.1 + + - New definition of user. + + Section 3 + + - Added 1.5 sentences at end of introductory paragraph indicating + the effect of the Bind op on the LDAP association. + +Harrison Expires April 2004 [Page 38] - Authentication Methods for LDAPv3 +Internet-Draft LDAP Authentication Methods 7 October 2003 + + Section 3.1 + + - Retitled section and clarified wording + + Section 3.2 + + - Clarified that simple authentication choice provides three types + of authentication: anonymous, unauthenticated, and simple + password. + + Section 3.3.3 + + - New wording clarifying when negotiated security mechanisms take + effect. + + Section 3.3.5 + + - Changed requirement to discard information about server fetched + prior to SASL negotion from MUST to SHOULD to allow for + information obtained through secure mechanisms. + + Section 3.3.6 + + - Simplified wording of first paragraph based on suggestion from + WG. + + Section 3.4 + + - Minor clarifications in wording. + + Section 3.4.1 + + - Minor larifications in wording in first sentence. + - Explicitly called out that the DN value in the dnAuthzID form is + to be matched using DN matching rules. + - Called out that the uAuthzID MUST be prepared using SASLprep + rules before being compared. + - Clarified requirement on assuming global uniqueness by changing + a "generally... MUST" wording to "SHOULD". + + Section 4.1.1 + + - Simplified wording describing conditions when Start TLS cannot + be sent. + - Simplified wording in note to implementers regarding race + condition with outstanding LDAP operations on connection. + + Section 4.1.5 + + - Removed section and moved relevant text to section 4.2.2. + + Section 4.1.6 + + +Harrison Expires April 2004 [Page 39] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + + - Renumbered to 4.1.5. + - Updated server identity check rules for server's name based on + WG list discussion. + + Section 4.1.7 + + - Renumbered to 4.1.6 + - Changed requirement to discard information about server fetched + prior to TLS negotion from MUST to SHOULD to allow for + information obtained through secure mechanisms. + + Section 6.1 + + - Clarified wording. + - Added definition of anonymous and unauthenticated binds. + + Section 10 + + - Added security consideration (moved from elsewhere) discouraging + use of cleartext passwords on unprotected communication + channels. + + Section 11 + + - Added an IANA consideration to update GSSAPI service name + registry to point to [Roadmap] and [Authmeth] + Appendix G. Issues to be Resolved This appendix lists open questions and issues that need to be @@ -1969,6 +2348,11 @@ G.3. Section 2, deployment scenario 2: What is meant by the term "secure authentication function?" + +Harrison Expires April 2004 [Page 40] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + Status: resolved. Based on the idea that a "secure authentication function" could be provided by TLS, I changed the wording to require @@ -1995,12 +2379,6 @@ G.5. reference is simply too arcane to be left in place. In -03 the text has been modified to focus on the need to either update password information in a protected fashion outside of the protocol or to - - -Harrison Expires September 2003 [Page 34] - - Authentication Methods for LDAPv3 - update it in session well protected against snooping, and the reference to /etc/passwd has been removed. @@ -2029,6 +2407,11 @@ G.8. Section 4 paragraph 9 indicates that clients SHOULD check the supportedSASLMechanisms list both before and after a SASL security + +Harrison Expires April 2004 [Page 41] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + layer is negotiated to ensure that they are using the best available security mechanism supported mutually by the client and server. A note at the end of the paragraph indicates that this is a SHOULD @@ -2055,11 +2438,6 @@ G.8. G.9. - -Harrison Expires September 2003 [Page 35] - - Authentication Methods for LDAPv3 - Section 6.3.1 states: "DSAs that map the DN sent in the bind request to a directory entry with a userPassword attribute will... compare [each value in the named user's entry]... with the presented @@ -2088,6 +2466,11 @@ G.10 userPassword and simple bind the bind request. G.11. Meaning of LDAP Association + +Harrison Expires April 2004 [Page 42] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + The original RFC 2830 uses the term "LDAP association" in describing a connection between an LDAP client and server regardless of the @@ -2114,11 +2497,6 @@ G.12. Is DIGEST-MD5 mandatory for all implementations? defined in section 6.1." The thing is for acl it would be nice (though not critical) to be - -Harrison Expires September 2003 [Page 36] - - Authentication Methods for LDAPv3 - able to default the required authentication level for a subject to a single "fairly secure" mechanism--if there is no such mandatory authentication scheme then you cannot do that. (Source: Rob Byrne) @@ -2147,6 +2525,11 @@ G.14. Document vulnerabilities of various mechanisms While I'm here...in 2829, I think it would be good to have some comments or explicit reference to a place where the security properties of the particular mandatory authentication schemes are + +Harrison Expires April 2004 [Page 43] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + outlined. When I say "security properties" I mean stuff like "This scheme is vulnerable to such and such attacks, is only safe if the key size is > 50, this hash is widely considered the best, etc...". @@ -2172,12 +2555,6 @@ G.15. Include a StartTLS state transition table members indicate that additional description of each state's meaning would be helpful. - - -Harrison Expires September 2003 [Page 37] - - Authentication Methods for LDAPv3 - G.16. Empty sasl credentials question I spent some more time looking microscopically at ldap-auth-methods @@ -2207,6 +2584,11 @@ G.17. Hostname check from MUST to SHOULD? solution! Wildcard match does not solve this problem. For these reasons I am inclined to argue for 'SHOULD' instead of 'MUST' in paragraph... + +Harrison Expires April 2004 [Page 44] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + Also, The hostname check against the name in the certificate is a very weak means of preventing man-in-the-middle attacks; the proper @@ -2221,7 +2603,7 @@ G.17. Hostname check from MUST to SHOULD? afterward is a SHOULD. This gives server implementations the room to maneuver as needed. - G.18. Must SASL DN exist in the directory? +G.18. Must SASL DN exist in the directory? If the 'dn:' form of sasl creds is used, is it the intention of the draft(ers) that this DN must exist in the directory and the client @@ -2232,11 +2614,6 @@ G.17. Hostname check from MUST to SHOULD? We already know that if *no* sasl credentials are presented, the DN or altname in the client certificate may be mapped to a DN in an implementation-dependent fashion, or indeed to something not in the - -Harrison Expires September 2003 [Page 38] - - Authentication Methods for LDAPv3 - directory at all. (Right?) (Source: ariel@columbia.edu via Jeff Hodges) @@ -2266,6 +2643,11 @@ G.19. DN used in conjunction with SASL mechanism G.20. Bind states + +Harrison Expires April 2004 [Page 45] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + Differences between unauthenticated and anonymous. There are four states you can get into. One is completely undefined (this is now explicitly called out in [Protocol]). This text needs to be moved @@ -2285,18 +2667,13 @@ G.21. Misuse of unauthenticated access requests that have a DN with an empty password with an error of invalidCredentials. (Source: Kurt Zeilenga and Chris Newman (Sun)) - Status: Resolved. Added to security considerations in รป03. + Status: Resolved. Added to security considerations in -03. G.22. Need to move StartTLS protocol information to [Protocol] Status: Resolved. Removed Sections 5.1, 5.2, and 5.4 for -04 and they are [Protocol] -11. -Harrison Expires September 2003 [Page 39] - - Authentication Methods for LDAPv3 - - G.23. Split Normative and Non-normative references into separate sections. @@ -2305,80 +2682,99 @@ sections. G.24. What is the authentication state if a Bind operation is abandoned? - Status: In process. (11/12/02) This text was suggested to be added - to [Protocol] -11 to cover what happens if a bind operation is - abandoned: + Status: Resolved. + + (3/24/03) This following text appears in section 4.2.1 of [Protocol] + revision -13 to cover what happens if a bind operation is abandoned: - "If a server receives an Abandon request for a Bind operation, the - server SHOULD leave the connection in the anonymous state. Clients - that abandon a Bind operation MUST rebind after abandoning the Bind - request in order to have a known authentication state on the - connection." - - (11/21/02) Jim Sermersheim prposed the following wording on the - ldapbis mail list: "Authentication from earlier binds are - subsequently ignored. A failed or abandoned Bind Operation has the - effect of leaving the connection in an anonymous state. Clients MUST - rebind after abandoning a bind operation in order to determine a - known authentication state." - - Once this is resolved in [Protocol] the state table in section 6 of - [AuthMeth] will need to be updated to reflect the consensus wording. + A failed or abandoned Bind Operation has the effect of leaving the + connection in an anonymous state. To arrive at a known + authentication state after abandoning a bind operation, clients may + unbind, rebind, or make use of the BindResponse. + + (6/28/03): The state table in section 6 of [AuthMeth] has been + updated to reflect this wording. G.25. Difference between checking server hostname and server's canonical DNS name in Server Identity Check? - Section 5.1.6: I now understand the intent of the check (prevent + Section 4.1.6: I now understand the intent of the check (prevent man-in-the-middle attacks). But what is the subtle difference between the "server hostname" and the "server's canonical DNS name"? (Source: Tim Hahn) + +Harrison Expires April 2004 [Page 46] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + - Status: In Process. (11/12/02) Sent suggested wording change to this - paragraph to the ldapbis mail list and also asked for opinion as to - whether we should discuss the distinction between server DNS - hostname and server canonical DNS hostname in [AuthMeth]. + Status: Resolved. + + (11/12/02) Sent suggested wording change to this paragraph to the + ldapbis mail list and also asked for opinion as to whether we should + discuss the distinction between server DNS hostname and server + canonical DNS hostname in [AuthMeth]. (11/21/02): RL Bob Morgan will provide wording that allows derivations of the name that are provided securely. -6.26. Server Identity Check using servers located via SRV records + (6/28/03): posted to the WG list asking Bob or any other WG member + who is knowledgeable about the issues involved to help me with + wording or other information I can use to make this change and close + the work item. + + (10/08/03): Based on WG list feedback, I've updated this text to + read what I judge to be the WG consensus, "The client MUST use the + server provided by the user (or other trusted entity) as the value + to compare against the server name as expressed in the server's + certificate. A hostname derived from the user input is to be + considered provided by the user only if derived in a secure fashion + (e.g., DNSSEC)." - Section 5.1.6: What should be done if the server was found using SRV + +G.26. Server Identity Check using servers located via SRV records + + Section 4.1.6: What should be done if the server was found using SRV records based on the "locate" draft/RFC? (Source: Tim Hahn). Status: Resolved. Section 5 of draft-ietf-ldapext-locate-08 specifically calls out how the server identity should be performed if the server is located using the method defined in that draft. - - -Harrison Expires September 2003 [Page 40] - - Authentication Methods for LDAPv3 - This is the right location for this information, and the coverage appears to be adequate. G.27 Inconsistency in effect of TLS closure on LDAP association. - Section 5.4.1 of authmeth -03 (section 4.1 of RFC2830) states that + Section 4.4.1 of authmeth -03 (section 4.1 of RFC2830) states that TLS closure alert will leave the LDAP association intact. Contrast - this with Section 5.5.2 (section 5.2 of RFC2830) that says that the + this with Section 4.5.2 (section 5.2 of RFC2830) that says that the closure of the TLS connection MUST cause the LDAP association to move to an anonymous authentication. - Status: in process. (11/12/02) This is actually a [Protocol] issue + Status: Resolved. (11/12/02) This is actually a [Protocol] issue because these sections have now been moved to [Protocol] -11. I have - proposed the following text for Section 5.4.1 of [AuthMeth] -03 + proposed the following text for Section 4.4.1 of [AuthMeth] -03 (section 4.13.3.1 of [Protocol]) to resolve this apparent discrepancy: "Either the client or server MAY terminate the TLS connection on an LDAP association by sending a TLS closure alert. The LDAP connection remains open for further communication after TLS closure + + +Harrison Expires April 2004 [Page 47] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + occurs although the authentication state of the LDAP connection is - affected (see [AuthMeth] section 5.2.2). + affected (see [AuthMeth] section 4.2.2). (11/21/02): resolution to this is expected in [Protocol] -12 + + (06/28/03): [Protocol]-15 clarifies that a TLS closure alert + terminates the TLS connection while leaving the LDAP connection + intact. The authentication state table in [AuthMeth] specifies the + effect on the LDAP association. G.28 Ordering of external sources of authorization identities @@ -2392,22 +2788,332 @@ G.28 Ordering of external sources of authorization identities states that the decision to allow or disallow the asserted identity is based on an implementation defined policy. -G.29 Rewrite of Section 10, TLS Ciphersuites +G.29 Rewrite of Section 9, TLS Ciphersuites This section contains anachronistic references and needs to be updated/rewritten in a way that provides useful guidance for future readers in a way that will transcend the passage of time. + Status: Resolved. (6/28/03): Rewrote the section to cover the + general issues and considerations involved in selecting TLS + ciphersuites. + G.30 Update to Appendix A, Example Deployment Scenarios This section needs to be updated to indicate which security mechanisms and/or combinations of security mechanisms described elsewhere in the document can provide the types of protections suggested in this appendix. - + +G.31 Use of PLAIN SASL Mechanism + + At least one LDAP server implementer has found the SASL "PLAIN" + mechanism useful in authenticating to legacy systems that do not + represent authentication identities as DNs. Section 3.3.1 appears to + implicitly disallow the use of the SASL "PLAIN" mechanism with LDAP. + Should we allow the use of this mechanism? I.e. is this "SASL" + "PLAIN" MUST NOT be used with LDAP, or is it simply that LDAP + doesn't define bindings for these mechanism. If SASL "PLAIN" is + allowed, the following adjustments will be needed to section 3.3.1: + (a) change section heading, (b) remove reference to "PLAIN" in the + section, (c) ensure wording of last sentence regarding non-DN + AuthZIDs is consistent with rest of the section. + + +Harrison Expires April 2004 [Page 48] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + + Status: Resolved. + + (6/28/03): email to WG list stating issue and asking if we should + remove the reference to SASL "PLAIN". + + For -07 draft I've generalized the SASL profile in section 3.3 to + allow any SASL mechanism. + + +G.32 Clarification on use of SASL mechanisms + + Section 3.3.1: BTW, what _are_ the "ANONYMOUS" and "PLAIN" SASL + mechanisms? They are not defined in RFC2222. If you refer to other + SASL mechanisms than those in rfc2222, Maybe you should only list + which mechanisms _are_used, instead of which ones are _not. (Source: + Hallvard Furuseth) + + I (Kurt Zeilenga) note[s] as well that the ANONYMOUS/PLAIN section + (4.2) should + be deleted. ANONYMOUS and PLAIN, like in other mechanism, + can be used in LDAP if a) supported and b) enabled. I note + that they each offer capabilities not found in their simple + bind equivalents (and hence are used in some deployments). + For example, PLAIN (over TLS) is quite useful when interacting + with legacy authentication subsystems. (Source: Kurt Zeilenga) + + Status: Resolved. + + For -07 draft I've generalized the SASL profile in section 3.3 to + allow any SASL mechanism. + + + +G.33 Clarification on use of password protection based on AuthZID form + + Section 3.3.1: "If an authorization identity of a form different + from a DN is requested by the client, a mechanism that protects the + password in transit SHOULD be used." What has that to do with DNs? + A mechanism that protects the password in transit should be used in + any case, shouldn't it? + + +G.34 Clarification on use of matching rules in Server Identity Check + + The text in section 4.1.6 isn't explicit on whether all rules apply + to both CN and dNSName values. The text should be clear as to which + rules apply to which values.... in particular, the wildcard + rules. (Source: Kurt Zeilenga) + + +G.35 Requested Additions to Security Considerations + + Requested to mention hostile servers which the user might have been + fooled to into contacting. Which mechanisms that are standardized by + +Harrison Expires April 2004 [Page 49] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + + the LDAP standard do/do not disclose the user's password to the + server? (Or to servers doing man-in-the-middle attack? Or is that a + stupid question?) + + Requested to mention denial of service attacks. + + Requested list of methods that need/don't need the server to know + the user's plaintext password. (I say 'know' instead of 'store' + because it could still store the password encrypted, but in a way + which it knows how to decrypt.) + + (Source: Hallvard Furuseth) + +G.36 Add reference to definition of DIGEST-MD5 + + Need a reference to the definition of DIGEST-MD5 SASL mechanism in + section 7.2 (Source: Hallvard Furuseth) + + Status: Resolved. A reference to to the DIGEST-MD5 SASL mechanism, + [DigestAuth], is included in the -07 revision. + +G.37 Clarification on procedure for certificate-based authentication + + + 8.1. Certificate-based authentication with TLS states: "Following + the successful completion of TLS negotiation, the client will send + an LDAP bind request with the SASL "EXTERNAL" mechanism." Is this + immediately following, or just some time later? Should the wording, + "the client will send..." actually read, "the client MUST send..."? + +G.38 Effect of StartTLS on authentication state + + Should the server drop all knowledge of connection, i.e. return to + anonymous state, if it gets a StartTLS request on a connection that + has successfully bound using the simple method? + +G.39 Be sure that there is a consideration in [SCHEMA] that discusses +multiple password values in userPassword + + Allowing multiple values obviously does raise a number of security + considerations and these need to be discussed in the document. + + Certainly applications which intend to replace the userPassword with + new value(s) should use modify/replaceValues (or + modify/deleteAttribute+addAttribute). Additionally, server + implementations should be encouraged to provide administrative + controls which, if enabled, restrict userPassword to one value. + +G.40. Clarify need to verify mapping between authentication identity +and resulting authorization identity on implicit assertion of AuthZID. + + 4.2.2.3. Error Conditions + + "For either form of assertion, the server MUST verify that the + +Harrison Expires April 2004 [Page 50] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + + client's authentication identity as supplied in its TLS credentials + is permitted to be mapped to the asserted authorization identity." + + This makes sense for the explicit assertion case, but seems to be + ambiguous for the implicit case. + IMHO, the mapping can be done as two steps: + a). deriving LDAP authentication identity from TLS credentials; If t + this steps fails, EXTERNAL mechanism returns failure. + b). verify that the authorization identity is allowed for the + derived authentication identity. This is always "noop" for the + implicit case. + I am not sure that the text is saying this. + (Source: Alexey Melnikov email 8/1/2003 5:30:43 PM) + + Status: Resolved in -07. After reading the comments and the text of + the draft, I believe that this should be clarified. The local policy + used to map the AuthNID to the AuthZID in the implicit case is + sufficient and that no additional verification is useful or needed. + This text has been moved to apply only to the explicit assertion + case. + +G.41. Section 7.2 contains unnecessary and misleading detail. + + " I am not sure why this section is required in the document. + DIGEST-MD5 is defined in a separate document and there should be + nothing magical about its usage in LDAP. If DIGEST-MD5 description + creates confusion for LDAP implementors, let's fix the DIGEST-MD5 + document! Also, this section tries to redefine DIGEST-MD5 behavior, + which is explicitly prohibited by the SASL specification." + (Source: Alexey Melnikov: email 8/1/2003 5:30:43 PM) + + Status: Resolved. + + After reading the comments and the text of the draft plus the + related text in draft-ietf-sasl-rfc2831bis-02.txt plus + http://www.ietf.org/internet-drafts/draft-ietf-sasl-rfc2222bis- + 02.txt, I am inclined to agree with Alexey. In -07 I rewrote section + 3.3 (SASL mechanisms) to match the profiling requirements + rfc2831bis. I then dramatically reduced the material in section 7.2 + to a bare minimum and let the SASL profile stand on its own. + +G.42. Does change for G.41 cause interoperability issue? + + There is one issue with the way the authmeth draft is currently + written that changes the SASL DIGEST-MD5 behavior on the way the + server responds with the subsequent authentication information . + This has been documented in this fashion since RFC 2829 (section + 6.1) was originally published and may cause an interoperability + issue at this point if it changed to follow the DIGEST-MD5 spec (as + it was in -07 of AuthMeth). Take this issue to the list. + + Status: Resolved + + + +Harrison Expires April 2004 [Page 51] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + + (10/08/03) This item was discussed on the WG list between 5/2/03 and + 5/9/03. Consensus apppears to support the notion that RFC 2829 was + in error and that the semantics of RFC 2831 are correct and should + be reflected in authmeth. This is already the case as of the -07 + draft. + +G.43. DIGEST-MD5 Realms recommendations for LDAP + + From http://www.ietf.org/internet-drafts/draft-ietf-sasl-rfc2222bis- + 02.txt: A protocol profile SHOULD provide a guidance how realms are + to be constructed and used in the protocol and MAY further restrict + its syntax and protocol-specific semantics." + + I don't believe that any such guidance exists within the LDAP TS. + The most likely place for this to reside is in the authmeth draft. + + Related email from Alexey Melnikov (8/4/2003 1:08:40 PM): + + "The problem I have with the document is that it references realm + without explaining what it is (or at least some examples of valid + values). For LDAP, some recommendations should be given. For + example: + 1). Use a hardcoded string as the realm (one of the implementations + I worked on was doing that) + 2). Use hostname (realm==host) or domain/cluster name (realm + includes multiple hosts). + 3). Use a node in DIT above user entry, for example for "cn=Barbara + Jensen, ou=Accounting, o=Ace Industry, c=US" + and "cn=John Doe, ou=Accounting, o=Ace Industry, c=US" realm can be + "ou=Accounting, o=Ace Industry, c=US" + (or "o=Ace Industry, c=US"); for "cn=Gern Jensen, ou=Product + Testing,o=Ace Industry, c=US" realm can be "ou=Product Testing, + o=Ace Industry, c=US". + + Of course other choices are possible. + + Alexey + + To summarize: I'd like authmeth to define a realm name for use with + Digest-MD5 that corresponds to LDAP DNs known to this server. + Authzid is okay, but perhaps could be better put into context. + + + John McMeeking (5/12/2003) + +G.44. Use of DNs in usernames and realms in DIGEST-MD5 + + In reading the discussion on the mailing list, I reach the following + conclusions: + + DIGEST-MD5 username and realm are simple strings. The syntax of + these strings allows strings that look like DNs in form, however, + DIGEST-MD5 treats them a simple strings for comparision purposes. + For example, the DNs cn=roger, o=US and cn=roger,o=us are equivalent + +Harrison Expires April 2004 [Page 52] + +Internet-Draft LDAP Authentication Methods 7 October 2003 + + when being compared semantically as DNs, however, these would be + considered two different username values in DIGEST-MD5 because + simple octet-wise semantics (rather than DN semantics) are used to + compare username values in DIGEST-MD5. Ditto for realm values. + + Status: Resolved. + + In -07 revision I added notes to implementors expressing this issue + in section 7.2. + +G.45: Open Issue: Is Simple+TLS mandatory to implement? + + Going forward, it would be much better to clarify that simple + +TLS is to be used for DN/password credentials and DIGEST-MD5 + (or PLAIN+TLS) be used for username/password credentials. (Kurt + Zeilenga, 5/12/2003) + + I don't believe you can mandate simple/TLS! At the time RFC 2829 was + debated, a large number on the WG wanted this. They did not get + their way because of the complexity of the solution. It was argued + that a password-based method would be better. I think they believed + it would still be DN/password, though. (Ron Ramsay, 5/12/2003) + + This was officially opened as an issue by WG co-chair Kurt Zeilenga + on 5/12/03. Little direct discussion has occurred since, however + there has been significant discussion on the use of DN values as the + username for DIGEST-MD5. + + + + + + + + + + + + + + + + + + + + + + + + -Harrison Expires September 2003 [Page 41] +Harrison Expires April 2004 [Page 53] diff --git a/doc/drafts/draft-ietf-ldapbis-dn-xx.txt b/doc/drafts/draft-ietf-ldapbis-dn-xx.txt index ac1882a6fb..da95fd3f3f 100644 --- a/doc/drafts/draft-ietf-ldapbis-dn-xx.txt +++ b/doc/drafts/draft-ietf-ldapbis-dn-xx.txt @@ -6,12 +6,14 @@ INTERNET-DRAFT Editor: Kurt D. Zeilenga Intended Category: Standard Track OpenLDAP Foundation -Expires in six months 4 May 2003 +Expires in six months 27 October 2003 Obsoletes: 2253 + LDAP: String Representation of Distinguished Names - + + Status of Memo @@ -23,7 +25,7 @@ Status of Memo revision, submitted to the RFC Editor as a Standard Track document replacing RFC 2253. Distribution of this memo is unlimited. Technical discussion of this document will take place on the IETF LDAP - Revision (LDAPbis) Working Group mailing list + Revision (LDAPBIS) Working Group mailing list . Please send editorial comments directly to the document editor . @@ -40,26 +42,30 @@ Status of Memo Internet-Draft Shadow Directories can be accessed at . - Copyright 2003, The Internet Society. All Rights Reserved. + Copyright (C) The Internet Society (2003). All Rights Reserved. + + Please see the Full Copyright section near the end of this document + for more information. + + - Please see the Copyright section near the end of this document for - more information. -Abstract - The X.500 Directory uses distinguished names (DNs) as primary keys to - entries in the directory. This document defines the string - representation used in the Lightweight Directory Access Protocol - (LDAP) to transfer distinguished names. The string representation is Zeilenga LDAP: Distinguished Names [Page 1] -INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 +INTERNET-DRAFT draft-ietf-ldapbis-dn-12.txt 27 October 2003 +Abstract + + The X.500 Directory uses distinguished names (DNs) as primary keys to + entries in the directory. This document defines the string + representation used in the Lightweight Directory Access Protocol + (LDAP) to transfer distinguished names. The string representation is designed to give a clean representation of commonly used distinguished names, while being able to represent any distinguished name. @@ -75,13 +81,14 @@ Conventions In X.500-based directory systems [X.500], including those accessed using the Lightweight Directory Access Protocol (LDAP) [Roadmap], - distinguished names (DNs) are used to unambiguously refer to a - directory entry [X.501][Models]. + distinguished names (DNs) are used to unambiguously refer to directory + entries [X.501][Models]. The structure of a DN [X.501] is described in terms of ASN.1 [X.680]. In the X.500 Directory Access Protocol [X.511] (and other ITU-defined directory protocols), DNs are encoded using the Basic Encoding Rules - (BER) [X.690]. In LDAP, DNs are represented in string form. + (BER) [X.690]. In LDAP, DNs are represented in the string form + described in this document. It is important to have a common format to be able to unambiguously represent a distinguished name. The primary goal of this @@ -89,8 +96,8 @@ Conventions to have names that are human readable. It is not expected that LDAP implementations with a human user interface would display these strings directly to the user, but would most likely be performing - translations (such as expressing attribute type names in one of the - local national languages). + translations (such as expressing attribute type names in the local + national language). This document defines the string representation of Distinguished Names used in LDAP [Protocol][Syntaxes]. Section 2 details the RECOMMENDED @@ -102,6 +109,13 @@ Conventions from its ASN.1 structured representation to a string, all algorithms MUST produce strings which adhere to the requirements of Section 3. + + +Zeilenga LDAP: Distinguished Names [Page 2] + +INTERNET-DRAFT draft-ietf-ldapbis-dn-12.txt 27 October 2003 + + This document does not define a canonical string representation for DNs. Comparison of DNs for equality is to be performed in accordance with the distinguishedNameMatch matching rule [Syntaxes]. @@ -109,13 +123,6 @@ Conventions This document is an integral part of the LDAP Technical Specification [Roadmap]. - - -Zeilenga LDAP: Distinguished Names [Page 2] - -INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 - - This document obsoletes RFC 2253. Changes since RFC 2253 are summarized in Appendix B. @@ -141,7 +148,7 @@ INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 This section defines the RECOMMENDED algorithm for converting a distinguished name from an ASN.1 structured representation to an UTF-8 - [RFC2279] encoded Universal Character Set (UCS) [ISO10646] character + [UTF-8] encoded Universal Character Set (UCS) [ISO10646] character string representation. Other documents may describe other algorithms for converting a distinguished name to a string, but only strings which conform to the grammar defined in Section 3 MUST be produced by @@ -158,19 +165,18 @@ INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 2.2), starting with the last element of the sequence and moving backwards toward the first. - The encodings of adjoining RelativeDistinguishedNames are separated by - a comma ("," U+002C) character. -2.2. Converting RelativeDistinguishedName +Zeilenga LDAP: Distinguished Names [Page 3] + +INTERNET-DRAFT draft-ietf-ldapbis-dn-12.txt 27 October 2003 + The encodings of adjoining RelativeDistinguishedNames are separated by + a comma ("," U+002C) character. -Zeilenga LDAP: Distinguished Names [Page 3] - -INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 - +2.2. Converting RelativeDistinguishedName When converting from an ASN.1 RelativeDistinguishedName to a string, the output consists of the string encodings of each @@ -189,14 +195,14 @@ INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 encoding of the AttributeValue is given in Section 2.4. If the AttributeType is defined to have a short name and that short - name is known to be registered [REGISTRY] as identifying the + name is known to be registered [REGISTRY][BCP64bis] as identifying the AttributeType, that short name, a , is used. Otherwise the AttributeType is encoded as the dotted-decimal encoding, a , of its OBJECT IDENTIFIER. The and is defined in [Models]. - Implementations are not expected dynamically update their knowledge of - registered short names. However, implementations SHOULD provide a + Implementations are not expected to dynamically update their knowledge + of registered short names. However, implementations SHOULD provide a mechanism to allow its knowledge of registered short names to be updated. @@ -214,19 +220,19 @@ INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 desired (see Section 5.2). Otherwise, if the AttributeValue is of a syntax which has a native - string encoding, the value is converted first to a UTF-8 encoded UCS - string according to its syntax specification (see for example Section - 6 of [Syntaxes]). If that UTF-8 encoded UCS string does not have any - of the following characters which need escaping, then that string can - be used as the string representation of the value. - Zeilenga LDAP: Distinguished Names [Page 4] -INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 +INTERNET-DRAFT draft-ietf-ldapbis-dn-12.txt 27 October 2003 + + string encoding, the value is converted first to a UTF-8 encoded UCS + string according to its syntax specification (see for example Section + 6 of [Syntaxes]). If that UTF-8 encoded UCS string does not have any + of the following characters which need escaping, then that string can + be used as the string representation of the value. - a space (" " U+0020) or number sign ("#" U+0023) occurring at the beginning of the string; @@ -259,7 +265,7 @@ INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 3. Parsing a String back to a Distinguished Name The string representation of Distinguished Names is restricted to - UTF-8 [RFC2279] encoded characters from the Universal Character Set + UTF-8 [UTF-8] encoded characters from the Universal Character Set (UCS) [ISO10646]. The structure of this string representation is specified using the following Augmented BNF [RFC2234] grammar: @@ -271,19 +277,18 @@ INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 attributeTypeAndValue = attributeType EQUALS attributeValue - attributeType = descr / numericoid - - attributeValue = string / hexstring - - ; The UTF-8 string shall not contain NULL, ESC, or - Zeilenga LDAP: Distinguished Names [Page 5] -INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 +INTERNET-DRAFT draft-ietf-ldapbis-dn-12.txt 27 October 2003 + attributeType = descr / numericoid + + attributeValue = string / hexstring + + ; The UTF-8 string shall not contain NULL, ESC, or ; one of escaped, shall not start with SHARP or SPACE, ; and shall must not end with SPACE. string = [ (leadchar / pair) @@ -327,19 +332,19 @@ INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 replace with ; replace with the octet indicated by the . - If in form, a BER representation can be obtained from - converting each of the to the octet indicated by - the . - - One or more attribute values assertions, separated by , for a Zeilenga LDAP: Distinguished Names [Page 6] -INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 +INTERNET-DRAFT draft-ietf-ldapbis-dn-12.txt 27 October 2003 + If in form, a BER representation can be obtained from + converting each of the to the octet indicated by + the . + + One or more attribute values assertions, separated by , for a relative distinguished name. Zero or more relative distinguished names, separated by , for a @@ -383,19 +388,19 @@ INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 OU=Sales+CN=J. Smith,DC=example,DC=net This example shows the method of escaping of a comma in a common - name: - - CN=John Smith\, III,DC=example,DC=net - - An example name in which a value contains a carriage return Zeilenga LDAP: Distinguished Names [Page 7] -INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 +INTERNET-DRAFT draft-ietf-ldapbis-dn-12.txt 27 October 2003 + + name: + + CN=John Smith\, III,DC=example,DC=net + An example name in which a value contains a carriage return character: CN=Before\0dAfter,DC=example,DC=net @@ -439,17 +444,19 @@ INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 - the common name of the object (i.e. a person's full name) - an email or TCP/IP address - - its physical location (country, locality, city, street address) - - organizational attributes (such as department name or affiliation) - - Most countries have privacy laws regarding the publication of - information about people. Zeilenga LDAP: Distinguished Names [Page 8] -INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 +INTERNET-DRAFT draft-ietf-ldapbis-dn-12.txt 27 October 2003 + + + - its physical location (country, locality, city, street address) + - organizational attributes (such as department name or affiliation) + + Most countries have privacy laws regarding the publication of + information about people. 5.2. Use of Distinguished Names in Security Applications @@ -491,78 +498,96 @@ INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 8. Normative References - [X.501] "The Directory -- Models," ITU-T Rec. X.501(1993). + [X.501] International Telecommunication Union - + Telecommunication Standardization Sector, "The Directory - [X.680] ITU-T, "Abstract Syntax Notation One (ASN.1) - - Specification of Basic Notation", X.680, 1994. - [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate - Requirement Levels", BCP 14 (also RFC 2119). - [RFC2234] Crocker, D., and P. Overell, "Augmented BNF for Syntax +Zeilenga LDAP: Distinguished Names [Page 9] + +INTERNET-DRAFT draft-ietf-ldapbis-dn-12.txt 27 October 2003 + -- Models," X.501(1993) (also ISO/IEC 9594-2:1994). -Zeilenga LDAP: Distinguished Names [Page 9] - -INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 + [X.680] International Telecommunication Union - + Telecommunication Standardization Sector, "Abstract + Syntax Notation One (ASN.1) - Specification of Basic + Notation", X.680(1997) (also ISO/IEC 8824-1:1998). + [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate + Requirement Levels", BCP 14 (also RFC 2119), March 1997. - Specifications: ABNF", RFC 2234, November 1997. + [RFC2234] Crocker, D. and P. Overell, "Augmented BNF for Syntax + Specifications: ABNF", RFC 2234, November 1997. - [RFC2279] Yergeau, F., "UTF-8, a transformation format of ISO - 10646", RFC 2279, January 1998. + [UTF-8] Yergeau, F., "UTF-8, a transformation format of ISO + 10646", draft-yergeau-rfc2279bis-xx.txt, a work in + progress. - [Models] K. Zeilenga (editor), "LDAP: Directory Information - Models", draft-ietf-ldapbis-models-xx.txt, a work in - progress. + [Models] Zeilenga, K. (editor), "LDAP: Directory Information + Models", draft-ietf-ldapbis-models-xx.txt, a work in + progress. - [Roadmap] K. Zeilenga, "LDAP: Technical Specification Road Map", - draft-ietf-ldapbis-roadmap-xx.txt, a work in progress. + [Roadmap] Zeilenga, K. (editor), "LDAP: Technical Specification + Road Map", draft-ietf-ldapbis-roadmap-xx.txt, a work in + progress. - [Protocol] J. Sermersheim (editor), "LDAP: The Protocol", - draft-ietf-ldapbis-protocol-xx.txt, a work in progress. + [Protocol] Sermersheim, J. (editor), "LDAP: The Protocol", + draft-ietf-ldapbis-protocol-xx.txt, a work in progress. - [Syntaxes] S. Legg (editor), "LDAP: Syntaxes", - draft-ietf-ldapbis-syntaxes-xx.txt, a work in progress. + [Syntaxes] Legg, S. (editor), "LDAP: Syntaxes and Matching Rules", + draft-ietf-ldapbis-syntaxes-xx.txt, a work in progress. - [Schema] K. Dally (editor), "LDAP: User Schema", - draft-ietf-ldapbis-user-schema-xx.txt, a work in - progress. + [Schema] Dally, K. (editor), "LDAP: User Schema", + draft-ietf-ldapbis-user-schema-xx.txt, a work in + progress. - [ISO10646] Universal Multiple-Octet Coded Character Set (UCS) - - Architecture and Basic Multilingual Plane, ISO/IEC - 10646-1 : 1993. + [ISO10646] International Organization for Standardization, + "Universal Multiple-Octet Coded Character Set (UCS) - + Architecture and Basic Multilingual Plane", ISO/IEC + 10646-1 : 1993. + [REGISTRY] IANA, Object Identifier Descriptors Registry, + . 9. Informative References - [X.500] "The Directory -- overview of concepts, models and - services," ITU-T Rec. X.500(1993). + [ASCII] Coded Character Set--7-bit American Standard Code for + Information Interchange, ANSI X3.4-1986. - [X.690] ITU-T, "Specification of ASN.1 encoding rules: Basic, - Canonical, and Distinguished Encoding Rules", X.690, - 1994. - [RFC3383] K. Zeilenga, "IANA Considerations for LDAP", BCP 64 (also - RFC 3383), September 2002. - [RFC2849] G. Good, "The LDAP Data Interchange Format (LDIF) - - Technical Specification", RFC 2849, June 2000. +Zeilenga LDAP: Distinguished Names [Page 10] + +INTERNET-DRAFT draft-ietf-ldapbis-dn-12.txt 27 October 2003 -Appendix A. Presentation Issues - This appendix is provided for informational purposes only, it is not a - normative part of this specification. + [X.500] International Telecommunication Union - + Telecommunication Standardization Sector, "The Directory + -- Overview of concepts, models and services," + X.500(1993) (also ISO/IEC 9594-1:1994). + [X.690] International Telecommunication Union - + Telecommunication Standardization Sector, "Specification + of ASN.1 encoding rules: Basic Encoding Rules (BER), + Canonical Encoding Rules (CER), and Distinguished + Encoding Rules (DER)", X.690(1997) (also ISO/IEC + 8825-1:1998). + [RFC2849] Good, G., "The LDAP Data Interchange Format (LDIF) - + Technical Specification", RFC 2849, June 2000. + + [BCP64bis] Zeilenga, K., "IANA Considerations for LDAP", draft- + ietf-ldapbis-bcp64-xx.txt, a work in progress. -Zeilenga LDAP: Distinguished Names [Page 10] - -INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 +Appendix A. Presentation Issues + + This appendix is provided for informational purposes only, it is not a + normative part of this specification. The string representation described in this document is not intended to be presented to humans without translation. However, at times it @@ -587,6 +612,14 @@ INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 demonstrated in the final example of Section 4). When a DN string is displayed in free form text, it is often necessary + + + +Zeilenga LDAP: Distinguished Names [Page 11] + +INTERNET-DRAFT draft-ietf-ldapbis-dn-12.txt 27 October 2003 + + to distinguish the DN string from surrounding text. While this is often done with white space (as demonstrated in Section 4), it is noted that DN strings may end with white space. Careful readers of @@ -612,14 +645,6 @@ INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 so it has been line-wrapped for readability. The extra white space is to be removed before the DN string is used in LDAP. - - - -Zeilenga LDAP: Distinguished Names [Page 11] - -INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 - - It is not advised to insert white space otherwise as it may not be obvious to the user which white space is part of the DN string and which white space was added for readability. @@ -642,18 +667,27 @@ Appendix B. Changes made since RFC 2253 The following substantive changes were made to RFC 2253: - Removed IESG Note. The IESG Note has been addressed. - - Clarified (in Section 1), that this document does not define a + - Clarified (in Section 1) that this document does not define a + + + +Zeilenga LDAP: Distinguished Names [Page 12] + +INTERNET-DRAFT draft-ietf-ldapbis-dn-12.txt 27 October 2003 + + canonical string representation. + - Revised specification (in Section 2) to allow short names of any + registered attribute type to appear in string representations of + DNs instead of being restricted to a "published table". Remove + "as an example" language. Added statement (in Section 3) allowing + recognition of additional names but require recognization of those + names in the published table. The table is now published in + Section 3. - Replaced specification of additional requirements for LDAPv2 implementations which also support LDAPv3 (RFC 2253, Section 4) with a statement (in Section 3) allowing recognition of alternative string representations. - - Clarified (in Section 2.3) that the "published" table of names - which may be appear in DNs is the table which Section 2.3 - provides. Remove "as an example" language. Noted this table is - not extensible. Added statement (in Section 3) allowing - recognition of additional names. Added security considerations - (Section 5.3) regarding the use of other names. - Updated Section 2.3 to indicate attribute type name strings are case insensitive. - Updated Section 2.4 to allow hex pair escaping of all characters @@ -669,21 +703,48 @@ Appendix B. Changes made since RFC 2253 - Added discussion of presentation issues (Appendix A). - Added this appendix. + In addition, numerous editorial changes were made. -Zeilenga LDAP: Distinguished Names [Page 12] +Intellectual Property Rights + + The IETF takes no position regarding the validity or scope of any + intellectual property or other rights that might be claimed to pertain + to the implementation or use of the technology described in this + document or the extent to which any license under such rights might or + might not be available; neither does it represent that it has made any + effort to identify any such rights. Information on the IETF's + procedures with respect to rights in standards-track and + standards-related documentation can be found in BCP-11. Copies of + claims of rights made available for publication and any assurances of + licenses to be made available, or the result of an attempt made to + obtain a general license or permission for the use of such proprietary + rights by implementors or users of this specification can be obtained + from the IETF Secretariat. + + The IETF invites any interested party to bring to its attention any + copyrights, patents or patent applications, or other proprietary + + + +Zeilenga LDAP: Distinguished Names [Page 13] -INTERNET-DRAFT draft-ietf-ldapbis-dn-10.txt 4 May 2003 +INTERNET-DRAFT draft-ietf-ldapbis-dn-12.txt 27 October 2003 + + + rights which may cover technology that may be required to practice + this standard. Please address the information to the IETF Executive + Director. - In addition, numerous editorial changes were made. +Full Copyright -Copyright 2003, The Internet Society. All Rights Reserved. + Copyright (C) The Internet Society (2003). All Rights Reserved. This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it - or assist in its implementation may be prepared, copied, published and + or assist in its implmentation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this @@ -694,15 +755,7 @@ Copyright 2003, The Internet Society. All Rights Reserved. copyrights defined in the Internet Standards process must be followed, or as required to translate it into languages other than English. - The limited permissions granted above are perpetual and will not be - revoked by the Internet Society or its successors or assigns. - This document and the information contained herein is provided on an - "AS IS" basis and THE AUTHORS, THE INTERNET SOCIETY, AND THE INTERNET - ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, - INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE - INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED - WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. @@ -727,5 +780,8 @@ Copyright 2003, The Internet Society. All Rights Reserved. -Zeilenga LDAP: Distinguished Names [Page 13] + + + +Zeilenga LDAP: Distinguished Names [Page 14] diff --git a/doc/drafts/draft-ietf-ldapbis-filter-xx.txt b/doc/drafts/draft-ietf-ldapbis-filter-xx.txt index 33790efcf2..8ef1d3ed2a 100644 --- a/doc/drafts/draft-ietf-ldapbis-filter-xx.txt +++ b/doc/drafts/draft-ietf-ldapbis-filter-xx.txt @@ -7,12 +7,12 @@ Network Working Group M. Smith, Editor Request for Comments: DRAFT Netscape Communications Corp. Obsoletes: RFC 2254 T. Howes -Expires: 28 August 2003 Opsware, Inc. - 28 February 2003 +Expires: 25 April 2004 Opsware, Inc. + 25 October 2003 LDAP: String Representation of Search Filters - + @@ -57,7 +57,7 @@ Expires: 28 August 2003 Opsware, Inc. Smith & Howes Intended Category: Standards Track [Page 1] -INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 +INTERNET-DRAFT LDAP: String Repres. of Search Filters 25 October 2003 3. Table of Contents @@ -72,15 +72,16 @@ INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 8. Security Considerations........................................7 9. Normative References...........................................7 10. Informative References.........................................8 -11. Acknowledgments................................................8 -12. Authors' Address...............................................8 -13. Full Copyright Statement.......................................9 -14. Appendix A: Changes Since RFC 2254.............................9 -14.1. Technical Changes...........................................9 -14.2. Editorial Changes...........................................10 -15. Appendix B: Changes Since Previous Document Revision...........11 -15.1. Technical Changes...........................................11 -15.2. Editorial Changes...........................................11 +11. Intellectual Property Rights...................................8 +12. Acknowledgments................................................8 +13. Authors' Address...............................................8 +14. Full Copyright Statement.......................................9 +15. Appendix A: Changes Since RFC 2254.............................9 +15.1. Technical Changes...........................................10 +15.2. Editorial Changes...........................................10 +16. Appendix B: Changes Since Previous Document Revision...........11 +16.1. Technical Changes...........................................12 +16.2. Editorial Changes...........................................12 4. Introduction @@ -110,10 +111,9 @@ INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 - Smith & Howes Intended Category: Standards Track [Page 2] -INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 +INTERNET-DRAFT LDAP: String Repres. of Search Filters 25 October 2003 Filter ::= CHOICE { @@ -160,7 +160,7 @@ INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 LDAPString ::= OCTET STRING -- UTF-8 encoded, -- ISO 10646 characters - where the LDAPString above is limited to the UTF-8 encoding [RFC2279] + where the LDAPString above is limited to the UTF-8 encoding [UTF-8] of the ISO 10646 character set [ISO10646]. The AttributeDescription is a string representation of the attribute description and is defined in [Protocol]. The AttributeValue and AssertionValue OCTET @@ -169,7 +169,7 @@ INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 Smith & Howes Intended Category: Standards Track [Page 3] -INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 +INTERNET-DRAFT LDAP: String Repres. of Search Filters 25 October 2003 STRING have the form defined in [Syntaxes]. The Filter is encoded @@ -201,10 +201,10 @@ INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 extensible = attr [dnattrs] [matchingrule] COLON EQUALS assertionvalue / [dnattrs] matchingrule COLON EQUALS assertionvalue / COLON EQUALS assertionvalue - present = attr EQUALS ASTERIX + present = attr EQUALS ASTERISK substring = attr EQUALS [initial] any [final] initial = assertionvalue - any = ASTERIX *(assertionvalue ASTERIX) + any = ASTERISK *(assertionvalue ASTERISK) final = assertionvalue attr = attributedescription ; The attributedescription rule is defined in @@ -219,18 +219,18 @@ INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 escaped = ESC HEX HEX UTF1SUBSET = %x01-27 / %x2B-5B / %x5D-7F ; UTF1SUBSET excludes 0x00 (NUL), LPAREN, - ; RPAREN, ASTERIX, and ESC. + ; RPAREN, ASTERISK, and ESC. Smith & Howes Intended Category: Standards Track [Page 4] -INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 +INTERNET-DRAFT LDAP: String Repres. of Search Filters 25 October 2003 EXCLAMATION = %x21 ; exclamation mark ("!") AMPERSAND = %x26 ; ampersand (or AND symbol) ("&") - ASTERIX = %x2A ; asterix ("*") + ASTERISK = %x2A ; asterisk ("*") COLON = %x3A ; colon (":") VERTBAR = %x7C ; vertical bar (or pipe) ("|") TILDE = %x7E ; tilde ("~") @@ -264,11 +264,11 @@ INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 As indicated by the valueencoding rule, implementations MUST escape all octets greater than 0x7F that are not part of a valid UTF-8 encoding sequence when they generate a string representation of a - search filter. Since RFC 2254 does not clearly define the term - "string representation" (and in particular does mention that the - string representation of an LDAP search filter is a string of UTF-8 - encoded ISO 10646-1 characters) implementations SHOULD accept as - input strings that include invalid UTF-8 octet sequences. + search filter. Implementations SHOULD accept as input a string that + includes invalid UTF-8 octet sequences. This is necessary because RFC + 2254 did not clearly define the term "string representation" (and in + particular did not mention that the string representation of an LDAP + search filter is a string of UTF-8 encoded ISO 10646-1 characters). 7. Examples @@ -281,7 +281,7 @@ INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 Smith & Howes Intended Category: Standards Track [Page 5] -INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 +INTERNET-DRAFT LDAP: String Repres. of Search Filters 25 October 2003 (!(cn=Tim Howes)) @@ -297,7 +297,6 @@ INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 (o:dn:=Ace Industry) (:1.2.3:=Wilma Flintstone) (:dn:2.4.6.8.10:=Dino) - (:=Fred Flintstone) The first example shows use of the matching rule "1.2.3.4.5". @@ -316,13 +315,10 @@ INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 The fifth example is a filter that should be applied to any attribute supporting the matching rule given (since the attr has been omitted). - The sixth example is also a filter that should be applied to any - attribute supporting the matching rule given. Attributes supporting - the matching rule contained in the DN should also be considered. - - The seventh and final example is a filter that should be applied to - any attribute (since both the attr and matching rule have been - omitted). + The sixth and final example is also a filter that should be applied + to any attribute supporting the matching rule given. Attributes + supporting the matching rule contained in the DN should also be + considered. The following examples illustrate the use of the escaping mechanism. @@ -333,16 +329,17 @@ INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 (sn=Lu\c4\8di\c4\87) (1.3.6.1.4.1.1466.0=\04\02\48\69) + The first example shows the use of the escaping mechanism to + represent parenthesis characters. The second shows how to represent a + "*" in an assertion value, preventing it from being interpreted as a + Smith & Howes Intended Category: Standards Track [Page 6] -INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 +INTERNET-DRAFT LDAP: String Repres. of Search Filters 25 October 2003 - The first example shows the use of the escaping mechanism to - represent parenthesis characters. The second shows how to represent a - "*" in an assertion value, preventing it from being interpreted as a substring indicator. The third illustrates the escaping of the backslash character. @@ -388,19 +385,16 @@ INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 [RFC2119] S. Bradner, "Key words for use in RFCs to Indicate Requirement Levels", BCP 14 (also RFC 2119), March 1997. + [RFC2234] Crocker, D., Overell, P., "Augmented BNF for Syntax + Specifications: ABNF", RFC 2234, November 1997. + Smith & Howes Intended Category: Standards Track [Page 7] -INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 - - - [RFC2234] Crocker, D., Overell, P., "Augmented BNF for Syntax - Specifications: ABNF", RFC 2234, November 1997. +INTERNET-DRAFT LDAP: String Repres. of Search Filters 25 October 2003 - [RFC2279] Yergeau, F., "UTF-8, a transformation format of ISO 10646", - RFC 2279, January 1998. [Roadmap] Zeilenga, K. (editor), "LDAP: Technical Specification Road Map", draft-ietf-ldapbis-roadmap-xx.txt, a work in progress. @@ -408,13 +402,36 @@ INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 [Syntaxes] Dally, K. (editor), "LDAP: Syntaxes", draft-ietf-ldapbis- syntaxes-xx.txt, a work in progress. + [UTF-8] Yergeau, F., "UTF-8, a transformation format of ISO 10646", + draft-yergeau-rfc2279bis-xx.txt, a work in progress. 10. Informative References None. - -11. Acknowledgments +11. Intellectual Property Rights + + The IETF takes no position regarding the validity or scope of any + intellectual property or other rights that might be claimed to + pertain to the implementation or use of the technology described in + this document or the extent to which any license under such rights + might or might not be available; neither does it represent that it + has made any effort to identify any such rights. Information on the + IETF's procedures with respect to rights in standards-track and + standards-related documentation can be found in BCP-11. Copies of + claims of rights made available for publication and any assurances of + licenses to be made available, or the result of an attempt made to + obtain a general license or permission for the use of such + proprietary rights by implementors or users of this specification can + be obtained from the IETF Secretariat. + + The IETF invites any interested party to bring to its attention any + copyrights, patents or patent applications, or other proprietary + rights which may cover technology that may be required to practice + this standard. Please address the information to the IETF Executive + Director. + +12. Acknowledgments This document replaces RFC 2254 by Tim Howes. Changes included in this revised specification are based upon discussions among the @@ -424,15 +441,23 @@ INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 acknowledged. -12. Authors' Address +13. Authors' Address Mark Smith, Editor + + + +Smith & Howes Intended Category: Standards Track [Page 8] + +INTERNET-DRAFT LDAP: String Repres. of Search Filters 25 October 2003 + + Netscape Communications Corp. 360 W. Caribbean Drive Sunnyvale, CA 94089 USA +1 650 937-3477 - mcs@netscape.com + MarkCSmithWork@aol.com Tim Howes Opsware, Inc. @@ -442,19 +467,9 @@ INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 +1 408 744-7509 howes@opsware.com +14. Full Copyright Statement - - - - -Smith & Howes Intended Category: Standards Track [Page 8] - -INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 - - -13. Full Copyright Statement - - Copyright (C) The Internet Society (2003). All Rights Reserved. + Copyright (C) The Internet Society (2003). All Rights Reserved. This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it @@ -481,9 +496,19 @@ INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. -14. Appendix A: Changes Since RFC 2254 +15. Appendix A: Changes Since RFC 2254 + + + + + + +Smith & Howes Intended Category: Standards Track [Page 9] + +INTERNET-DRAFT LDAP: String Repres. of Search Filters 25 October 2003 + -14.1. Technical Changes +15.1. Technical Changes The following technical changes were made to the contents of the "String Search Filter Definition" section: @@ -501,13 +526,6 @@ INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 precisely reference productions from the [Models] and [Protocol] documents. - - -Smith & Howes Intended Category: Standards Track [Page 9] - -INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 - - Introduced the "valueencoding" and associated "normal" and "escaped" rules to reduce the dependence on descriptive text. The "normal" production restricts filter strings to valid UTF-8 sequences. @@ -519,7 +537,7 @@ INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 of a clear definition of "string representation." -14.2. Editorial Changes +15.2. Editorial Changes Changed document title to include "LDAP:" prefix. @@ -529,14 +547,23 @@ INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 Header and "Authors' Addresses" sections: added Mark Smith as the document editor and updated affiliation and contact information. - "Table of Contents" section: added. + "Table of Contents" and "Intellectual Property Rights" sections: + added. - Copyright: updated the year. + Copyright: updated per latest IETF guidelines. "Abstract" section: separated from introductory material. "Introduction" section: new section; separated from the Abstract. Updated second paragraph to indicate that RFC 2254 is replaced by + + + +Smith & Howes Intended Category: Standards Track [Page 10] + +INTERNET-DRAFT LDAP: String Repres. of Search Filters 25 October 2003 + + this document (instead of RFC 1960). Added reference to the [Roadmap] document. @@ -550,27 +577,19 @@ INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 escaped is replaced by a backslash and two hex digits, which represent a single octet. - "Examples" section: added five additional examples: (seeAlso=), - (cn:=Betty Rubble), (:1.2.3:=Wilma Flintstone), (:=Fred Flintstone), - and (1.3.6.1.4.1.1466.0=\04\02\48\69). Replaced one occurrence of "a + "Examples" section: added four additional examples: (seeAlso=), + (cn:=Betty Rubble), (:1.2.3:=Wilma Flintstone), and + (1.3.6.1.4.1.1466.0=\04\02\48\69). Replaced one occurrence of "a value" with "an assertion value". "Security Considerations" section: added references to [Protocol] and - - - -Smith & Howes Intended Category: Standards Track [Page 10] - -INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 - - [AuthMeth]. "Normative References" section: renamed from "References" per new RFC guidelines. Changed from [1] style to [Protocol] style throughout the document. Added entries for [ISO10646], [RFC2119], [AuthMeth], - [Models], and [Roadmap] and updated UTF-8 reference to RFC 2279. - Replaced RFC 822 reference with a reference to RFC 2234. + [Models], and [Roadmap] and updated the UTF-8 reference. Replaced + RFC 822 reference with a reference to RFC 2234. "Informative References" section: added for clarity. @@ -582,72 +601,53 @@ INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 added. -15. Appendix B: Changes Since Previous Document Revision +16. Appendix B: Changes Since Previous Document Revision - This appendix lists all changes relative to the last published - revision, draft-ietf-ldapbis-filter-03.txt. Note that when + This appendix lists all changes relative to the previously published + revision, draft-ietf-ldapbis-filter-04.txt. Note that when appropriate these changes are also included in Appendix A, but are also included here for the benefit of the people who have already - reviewed draft-ietf-ldapbis-filter-03.txt. This section will be + reviewed draft-ietf-ldapbis-filter-04.txt. This section will be removed before this document is published as an RFC. -15.1. Technical Changes - - "String Search Filter Definition" section: Added statement that the - string representation is a string of UTF-8 encoded ISO 10646-1 - characters and statement about expected behavior in light of RFC - 2254's lack of a clear definition of "string representation." - - "String Search Filter Definition" section: Revised all of the ABNF to - use common productions from [Models]. Revised the "normal" - production to restrict filter strings to valid UTF-8 sequences. - - -15.2. Editorial Changes - - "Status of this Memo" section: updated boilerplate to match current - I-D guidelines. - - "Examples" section: removed ;binary from an example. - "LDAP Search Filter Definition " section: updated section references Smith & Howes Intended Category: Standards Track [Page 11] -INTERNET-DRAFT LDAP: String Repres. of Search Filters 28 February 2003 - - - to match current LDAPBis drafts. Made minor changes to the ASN.1 so - it exactly matches that used in the Protocol document (added - comments). - - "Normative References" section: added references to [ISO10646], - [RFC2119] and [Models]. - - "Informative References" section: added for clarity. - - Updated copyright year to 2003. - - -This Internet Draft expires on 28 August 2003. - - +INTERNET-DRAFT LDAP: String Repres. of Search Filters 25 October 2003 +16.1. Technical Changes + "Examples" section: Removed the (:=Fred Flintstone) example which is + not allowed by the protocol. +16.2. Editorial Changes + "String Search Filter Definition" section: Revised the last two + sentences in this section to improve clarity (the updated text now + begins with the text "Implementations SHOULD accept as input a string + that includes...." + Replaced all occurrences of "asterix" with the correctly spelled + "asterisk." + "Normative References" section: changed UTF-8 reference to point to + the UTF-8 Internet Draft. + "Intellectual Property Rights" section: added. + Author's Addresses section: New email address for Mark Smith. + "Full Copyright Statement" section: updated text to match latest IETF + guidelines. +This Internet Draft expires on 25 April 2004. diff --git a/doc/drafts/draft-ietf-ldapbis-models-xx.txt b/doc/drafts/draft-ietf-ldapbis-models-xx.txt index 38d44aa8cb..90b6048534 100644 --- a/doc/drafts/draft-ietf-ldapbis-models-xx.txt +++ b/doc/drafts/draft-ietf-ldapbis-models-xx.txt @@ -6,13 +6,13 @@ INTERNET-DRAFT Editor: Kurt D. Zeilenga Intended Category: Standard Track OpenLDAP Foundation -Expires in six months 1 March 2003 +Expires in six months 27 October 2003 Obsoletes: RFC 2251, RFC 2252, RFC 2256 LDAP: Directory Information Models - + @@ -40,9 +40,10 @@ Status of this Memo Internet-Draft Shadow Directories can be accessed at . - Copyright 2003, The Internet Society. All Rights Reserved. Please - see the Copyright section near the end of this document for more - information. + Copyright (C) The Internet Society (2003). All Rights Reserved. + + Please see the Full Copyright section near the end of this document + for more information. Abstract @@ -54,10 +55,9 @@ Abstract - Zeilenga LDAP Models [Page 1] -INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 +INTERNET-DRAFT draft-ietf-ldapbis-models-09 27 October 2003 Table of Contents @@ -67,53 +67,56 @@ Table of Contents Table of Contents 2 1. Introduction 3 1.1. Relationship to Other LDAP Specifications - 1.2. Relationship to ITU Specifications - 1.3. Conventions 4 + 1.2. Relationship to X.501 4 + 1.3. Conventions 1.4. Common ABNF Productions 2. Model of Directory User Information 6 - 2.1. The Directory Information Tree - 2.2. Naming of Entries 7 + 2.1. The Directory Information Tree 7 + 2.2. Naming of Entries 2.3. Structure of an Entry 8 - 2.4. Object Classes + 2.4. Object Classes 9 2.5. Attribute Descriptions 11 2.6. Alias Entries 15 - 3. Directory Administrative and Operational Information 16 + 3. Directory Administrative and Operational Information 17 3.1. Subtrees - 3.2. Subentries 17 - 3.3. The 'objectClass' attribute - 3.4. Operational attributes 18 - 4. Directory Schema 20 - 4.1. Schema Definitions 21 - 4.2. Subschema Subentries 30 + 3.2. Subentries + 3.3. The 'objectClass' attribute 18 + 3.4. Operational attributes + 4. Directory Schema 21 + 4.1. Schema Definitions 22 + 4.2. Subschema Subentries 31 4.3. 'extensibleObject' 34 - 4.4. Subschema Discovery + 4.4. Subschema Discovery 35 5. DSA (Server) Informational Model - 5.1. Server-specific Data Requirements 35 - 6. Other Considerations 38 + 5.1. Server-specific Data Requirements 36 + 6. Other Considerations 39 6.1. Preservation of User Information 6.2. Short Names - 6.3. Cache and Shadowing 39 - 7. Implementation Guidelines 40 + 6.3. Cache and Shadowing 40 + 7. Implementation Guidelines 7.1. Server Guidelines - 7.2. Client Guidelines - 8. Security Considerations 41 + 7.2. Client Guidelines 41 + 8. Security Considerations 9. IANA Considerations 10. Acknowledgments 42 11. Author's Address - 12. References + 12. References 43 12.1. Normative References - 12.2. Informative References 43 + 12.2. Informative References 44 Appendix A. Changes A.1 Changes to RFC 2251 44 A.2 Changes to RFC 2252 46 - A.3 Changes to RFC 2256 47 - Copyright + A.3 Changes to RFC 2256 48 + Intellectual Property Rights Zeilenga LDAP Models [Page 2] -INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 +INTERNET-DRAFT draft-ietf-ldapbis-models-09 27 October 2003 + + + Full Copyright 49 1. Introduction @@ -161,20 +164,20 @@ INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 This document obsoletes RFC 2251 sections 3.2 and 3.4, as well as portions of sections 4 and 6. Appendix A.1 summaries changes to these - sections. The remainder of RFC 2251 is obsoleted by the [Protocol], - [AuthMeth], and [Roadmap] documents. - Zeilenga LDAP Models [Page 3] -INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 +INTERNET-DRAFT draft-ietf-ldapbis-models-09 27 October 2003 + sections. The remainder of RFC 2251 is obsoleted by the [Protocol], + [AuthMeth], and [Roadmap] documents. + This document obsoletes RFC 2252 sections 4, 5 and 7. Appendix A.2 summaries changes to these sections. The remainder of RFC 2252 is - obsoleted by [Syntaxes] and [Schema]. + obsoleted by [Syntaxes]. This document obsoletes RFC 2256 sections 5.1, 5.2, 7.1 and 7.2. Appendix A.3 summarizes changes to these sections. The remainder of @@ -184,8 +187,8 @@ INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 1.2. Relationship to X.501 This document includes material, with and without adaptation, from the - [X.501]. Due to the adaptation, the material included in this - document takes precedence. + [X.501]. The material in this document takes precedence over that in + [X.501]. 1.3. Conventions @@ -217,17 +220,17 @@ INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 DIGIT = %x30 / LDIGIT ; "0"-"9" LDIGIT = %x31-39 ; "1"-"9" - HEX = DIGIT / %x41-46 / %x61-66 ; 0-9 / A-F / a-f - - SP = 1*SPACE ; one or more " " Zeilenga LDAP Models [Page 4] -INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 +INTERNET-DRAFT draft-ietf-ldapbis-models-09 27 October 2003 + + HEX = DIGIT / %x41-46 / %x61-66 ; 0-9 / A-F / a-f + SP = 1*SPACE ; one or more " " WSP = 0*SPACE ; zero or more " " NULL = %x00 ; null (0) @@ -254,35 +257,36 @@ INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 ; Any UTF-8 character UTF8 = UTF1 / UTFMB - UTFMB = UTF2 / UTF3 / UTF4 / UTF5 / UTF6 + UTFMB = UTF2 / UTF3 / UTF4 UTF0 = %x80-BF UTF1 = %x00-7F - UTF2 = %xC0-DF 1(UTF0) - UTF3 = %xE0-EF 2(UTF0) - UTF4 = %xF0-F7 3(UTF0) - UTF5 = %xF8-FB 4(UTF0) - UTF6 = %xFC-FD 5(UTF0) + UTF2 = %xC2-DF UTF0 + UTF3 = %xE0 %xA0-BF UTF0 / %xE1-EC 2(UTF0) / + %xED %x80-9F UTF0 / %xEE-EF 2(UTF0) + UTF4 = %xF0 %x90-BF 2(UTF0) / %xF1-F3 3(UTF0) / + %xF4 %x80-8F 2(UTF0) ; Any octet OCTET = %x00-FF - Object identifiers are represented in LDAP using a dot-decimal format - conforming to the ABNF: + Object identifiers (OIDs) [X.680] are represented in LDAP using a dot- + decimal format conforming to the ABNF: numericoid = number *( DOT number ) Short names, also known as descriptors, are used as more readable aliases for object identifiers. Short names are case insensitive and - conform to the ABNF: - - descr = keystring Zeilenga LDAP Models [Page 5] -INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 +INTERNET-DRAFT draft-ietf-ldapbis-models-09 27 October 2003 + + conform to the ABNF: + + descr = keystring Where either an object identifier or a short name may be specified, the following production is used: @@ -329,16 +333,15 @@ INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 provides alternative naming. A subentry holds administrative and/or operational information. - The set of entries representing the DIB are organized hierarchically - in a tree structure known as the Directory Information Tree (DIT). - - Zeilenga LDAP Models [Page 6] -INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 +INTERNET-DRAFT draft-ietf-ldapbis-models-09 27 October 2003 + + The set of entries representing the DIB are organized hierarchically + in a tree structure known as the Directory Information Tree (DIT). Section 2.1 describes the Directory Information Tree Section 2.2 discusses naming of entries. @@ -386,16 +389,14 @@ INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 immediate subordinates of the entry's immediate superior (i.e., all siblings). - The following are example string representations of RDNs [LDAPDN]: - - Zeilenga LDAP Models [Page 7] -INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 +INTERNET-DRAFT draft-ietf-ldapbis-models-09 27 October 2003 + The following are example string representations of RDNs [LDAPDN]: UID=12345 OU=Engineering CN=Kurt Zeilenga+L=Redwood Shores @@ -446,10 +447,9 @@ INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 - Zeilenga LDAP Models [Page 8] -INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 +INTERNET-DRAFT draft-ietf-ldapbis-models-09 27 October 2003 Two values are considered equivalent if they would match according to @@ -505,7 +505,7 @@ INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 Zeilenga LDAP Models [Page 9] -INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 +INTERNET-DRAFT draft-ietf-ldapbis-models-09 27 October 2003 allowed to be present in entries belonging to the class. As an entry @@ -561,7 +561,7 @@ INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 Zeilenga LDAP Models [Page 10] -INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 +INTERNET-DRAFT draft-ietf-ldapbis-models-09 27 October 2003 Structural object classes are related to associated entries: @@ -617,7 +617,7 @@ INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 Zeilenga LDAP Models [Page 11] -INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 +INTERNET-DRAFT draft-ietf-ldapbis-models-09 27 October 2003 2.5.1) and a set of zero or more attribute options (see Section @@ -673,7 +673,7 @@ INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 Zeilenga LDAP Models [Page 12] -INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 +INTERNET-DRAFT draft-ietf-ldapbis-models-09 27 October 2003 syntax of its supertype. An attribute type cannot be a subtype of an @@ -695,7 +695,7 @@ INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 Not all options can be associated with attributes held in the directory. Tagging options can be. - Not all options can be use in conjunction with all attribute types. + Not all options can be used in conjunction with all attribute types. In such cases, the attribute description is to be treated as unrecognized. @@ -716,7 +716,7 @@ INTERNET-DRAFT draft-ietf-ldapbis-models-07 1 March 2003 conforming to the