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diff --git a/third_party/heimdal/doc/standardisation/draft-ietf-krb-wg-kerberos-set-passwd-02.txt b/third_party/heimdal/doc/standardisation/draft-ietf-krb-wg-kerberos-set-passwd-02.txt new file mode 100644 index 00000000000..a25d8096ca4 --- /dev/null +++ b/third_party/heimdal/doc/standardisation/draft-ietf-krb-wg-kerberos-set-passwd-02.txt @@ -0,0 +1,1793 @@ + +Kerberos Working Group Nicolas Williams +INTERNET-DRAFT Sun Microsystems +Category: Standards Track Jonathan Trostle + Cisco Systems + + + + Kerberos Set/Change Password: Version 2 + <draft-ietf-krb-wg-kerberos-set-passwd-02.txt> + +Status of this Memo + + By submitting this Internet-Draft, I certify that any applicable + patent or other IPR claims of which I am aware have been disclosed, + and any of which I become aware will be disclosed, in accordance with + RFC 3668. + + Internet-Drafts are working documents of the Internet Engineering + Task Force (IETF), its areas, and its working groups. Note that + other groups may also distribute working documents as + Internet-Drafts. + + Internet-Drafts are draft documents valid for a maximum of six months + and may be updated, replaced, or obsoleted by other documents at any + time. It is inappropriate to use Internet-Drafts as reference + material or to cite them other than as "work in progress." + + The list of current Internet-Drafts can be accessed at + http://www.ietf.org/ietf/1id-abstracts.txt. + + The list of Internet-Draft Shadow Directories can be accessed at + http://www.ietf.org/shadow.html. + + This Internet-Draft will expire on January 12, 2005. + +Copyright Notice + + Copyright (C) The Internet Society (2004). All Rights Reserved. + +Abstract + + This document specifies an extensible protocol for setting keys and + changing the passwords of Kerberos V principals. + +Table of Contents + + 1 Introduction + 2 The Protocol + 2.1 Transports + 2.2 Protocol Framing + 2.3 Protocol version negotiation + 2.3.1 Protocol Major Version Negotiation + 2.3.2 Protocol Minor Version Negotiation + 2.4 Use of Kerberos V + +N. Williams et. al. [Page 1] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + 2.5 Use of ASN.1 + 2.6 Internationalization + 2.6.1 Normalization Forms for UTF-8 Strings + 2.6.2 Language Negotiation + 2.7 Protocol Extensibility + 2.8 Protocol Subsets + 3 Protocol Elements + 3.1 PDUs + 3.2 Operations + 3.2.1 Null + 3.2.2 Change Kerberos Password + 3.2.3 Set Kerberos Password + 3.2.4 Set Kerberos Keys + 3.2.5 Generate Kerberos Keys + 3.2.6 Get New Keys + 3.2.7 Commit New Keys + 3.2.8 Get Password Quality Policy + 3.2.9 Get Principal Aliases + 3.2.10 Get Realm's Supported Kerberos V Version and Features + 4 ASN.1 Module + 6 IANA Considerations + 7 Security Considerations + 8 Acknowledgements + 9 References + 9.1 Normative References + 9.2 Informative References + 10 Authors' Addresses + 11 Notes to the RFC Editor + +Conventions used in this document + + The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", + "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this + document are to be interpreted as described in [RFC2119]. + +1 Introduction + + Up to this point Kerberos V has lacked a single, standard protocol + for changing passwords and keys. While several vendor-specific + protocols exist for changing Kerberos passwords/keys, none are + properly internationalized and all are incomplete in one respect or + another and none are sufficiently extensible to cope with new + features that may be added to Kerberos V at some future time. + + This document defines a protocol that is somewhat backward-compatible + with the "kpasswd" protocol defined in [RFC3244] that uses more or + less the same protocol framing. + + This new protocol is designed to be extensible and properly + internationalized. + +2 The Protocol + + +N. Williams et. al. [Page 2] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + The structure of the protocol is quite similar to that of typical RPC + protocols. Each transaction consists of a data structure specific to + an operation which is then wrapped in a data structure which is + general to all operations of the protocol. These data structures are + defined with the Abstract Syntax Notation 1 (ASN.1) [X680] and they + are encoded using the Distinguished Encoding Rules (DER) [X690]. + + All protocol data is wrapped KRB-PRIV messages, or, in some cases, a + KRB-ERROR, and framed in a header that is backwards compatible with + [RFC3244]. + +2.1 Transports + + The service supports only connection-oriented transports, + specifically TCP, and MUST accept requests on TCP port 464, the same + as in [RFC3244]. + +2.2 Protocol Framing + + Requests and responses are exchanged using the same framing as in + [RFC3244], but with the following differences: + + - the protocol number field MUST be set to 0x2 (not 0xff80 or 0x1) + + - the 'AP-REQ length' field of the request can be set to 0x0, in + which case the 'AP-REQ' field of the request is excluded + + - the 'KRB-PRIV' field of the request and reply is mutually + exclusive with the 'AP-REQ' field of the request + + - the 'AP-REP length' field of the reply can be set to 0x0, in + which case the 'AP-REP' field of the reply is excluded + + - all errors MUST be sent in a KRB-PRIV if the client's AP-REQ can + be or has been accepted by the server + + - any KRB-ERROR messages are framed and sent in the 'AP-REP' field + of the reply + + The initial message from the client MUST carry an AP-REQ and the + response to any request bearing an AP-REQ MUST carry an AP-REP or + MUST be a KRB-ERROR. + + Subsequent messages exchanged on the same TCP connection MAY involve + Kerberos V AP exchanges, but generally the client SHOULD NOT initiate + a new AP exchange except when it desires to authenticate as a + different principal, when the ticket last used for authentication + expires or when the server responds with an error indicating that the + client must re-authenticate. + +2.3 Protocol Version Negotiation + + There are several major versions of this protocol. Version 2 also + +N. Williams et. al. [Page 3] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + introduces a notion of protocol minor versions for use in negotiating + protocol extensions. As of this time only one minor version is + defined for major version 2: minor version 0, defined herein. + +2.3.1 Protocol Major Version Negotiation + + Version 2 clients that also support other versions, such as 0xff80, + as in [RFC3244], SHOULD attempt to use version 2 of the protocol + first. + + Servers which do not support version 2 of this protocol typically + include their preferred version number in the reply and/or may + include a reply in the e-data of a KRB-ERROR, or in a KRB-PRIV with a + status code of KRB5_KPASSWD_MALFORMED. + + Note that some [RFC3244] server implementations close the TCP + connection without returning any other response. Note also that + there is no integrity protection for the major version number in the + protocol framing or for any data in a KRB-ERROR. + + As a result change password protocol major version negotiation is + subject to downgrade attacks. Therefore major version negotiation is + NOT RECOMMENDED. + + Where the server indicates that it does not support version 2, the + client MAY, but SHOULD NOT, unless configured to do so, fall back on + another major version of this protocol. + + Version 2 servers MAY respond to non-v2 requests using whatever + response is appropriate for the versions used by the clients, but if + a server does not do this or know how to do this then it MUST respond + with an error framed as in section 2.2, using an AP-REP and KRB-PRIV + if the client's AP-REQ can be accepted, or a KRB-ERROR otherwise and + using a ProtocolErrorCode value of unsupported-major-version. + + It is expected that implementations of as yet unspecified future + major versions of this protocol will be required to support version 2 + integrity protected error replies for properly indicating no support + for version 2 of the protocl. We also hope that no further major + versions of this protocol will be needed. + +2.3.2 Protocol Minor Version Negotiation + + Version 2 clients are free to use whatever protocol minor version and + message extensions are available to them in their initial messages to + version 2 servers, provided that the minor versions (other than 0) + have been defined through IETF documents. + + Version 2 servers MUST answer with the highest protocol minor version + number supported by the server and the client. + + Version 2 clients MUST use the protocol minor version used in a + server's reply for any subsequent messages in the same TCP session. + +N. Williams et. al. [Page 4] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + + See section 2.7 for further description of the protocol's + extensibility and its relation to protocol minor versions and the + negotiation thereof. + +2.4 Use of Kerberos V and Key Exchange + + This protocol makes use of messages defined in [RFC1510] and + [clarifications]. Specifically, AP-REQ, AP-REP, KRB-ERROR and + KRB-PRIV. + + All operations are to be performed by the server on behalf of the + client principal. + + Clients SHOULD use "kadmin/setpw" as the principal name of the server + for all requests except when changing the client principal's own + expired password, for which they should use "kadmin/changepw". The + "kadmin/changepw" service exists to allow KDCs to limit principals + with expired passwords to getting initial tickets to the password + changing service only and only for changing expired passwords. + + Servers MUST limit clients that used the "kadmin/changepw" service + principal name to changing the password of the client principal. + + The client MUST request mutual authentication and the client MUST + MUST request the use of sequence numbers. + + Clients SHOULD use INITIAL tickets for requests whose target + principal is the client's principal. Servers SHOULD force the use of + INITIAL tickets for such requests and MAY force the use of INITIAL + for all others - see section 3.2. + + Servers MUST specify a sub-session key. + + The encrypted part of KRB-PRIVs MUST be encrypted with the server's + sub-session key and key usage 20 (client->server) or 21 + (server->client). + + After each new AP exchange the client and server MUST destroy the + session keys, if any, resulting from the previous AP exchange. + +2.5 Use of ASN.1 + + This protocol's messages are defined in ASN.1, using only features + from [X680]. All ASN.1 types defined herein are to be encoded in + DER [X690]. A complete ASN.1 module is given in section 4. + + The DER encoding of the ASN.1 PDUs are exchanged wrapped in a + KRB-PRIV as described above and/or as e-data in KRB-ERROR messages. + +2.6 Internationalization + + This protocol's request PDU carries an optional field indicating the + +N. Williams et. al. [Page 5] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + languages spoken by the client user; the client SHOULD send its list + of spoken languages to the server (once per-TCP session). + + The server SHOULD localize all strings intended for display to users + to a language in common with the languages spoken by the client user. + + Strings for Kerberos principal and realm names used in this protocol + are be constrained as per [clarifications]. + +2.6.1 Normalization Forms for UTF-8 Strings + + Because Kerberos V [clarifications] restricts principal names, realm + names and passwords to IA5String, this protocol uses UTF8String with + an extensible constraint to IA5String. + + Future versions of Kerberos may relax this constraint; if so then a + minor version of this protocol should relax this constraint + accordingly. + +2.6.2 Language Negotiation + + The server MUST pick a language from the client's input list or + the default language tag (see [RFC3066]) for text in its responses + which is meant for the user to read. + + The server SHOULD use a language selection algorithm such that + consideration is first given to exact matches between the client's + spoken languages and the server's available locales, followed by + "fuzzy" matches where only the first sub-tags of the client's + language tag list are used for matching against the servers available + locales. + + Servers MUST cache the optional language tag lists from prior + requests for use with subsequent requests that exclude the language + tag list. Clients MAY expect such server behaviour and send the + language tag lists only once per-TCP session. Clients SHOULD send + the server the language tag list at least once. + + When the server has a message catalog for one of the client's spoken + languages the server SHOULD localize any text strings intended for + display to users. + +2.7 Protocol Extensibility + + The protocol is defined in ASN.1 and uses extensibility markers + throughout. As such, the module presented herein can be extended + within the framework of [X680]. + + Typed holes are not used in this protocol as it is very simple and + does not require the ability to deal with abstract data types defined + in different layers. For this reason, the only way to extend this + protocol is by extending the ASN.1 module within the framework of the + IETF; all future extensions to this protocol have to be defined in + +N. Williams et. al. [Page 6] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + IETF documents unless otherwise specified in a future IETF revision + of this protocol. + + A protocol minor version number is used to negotiate use of + extensions. See section 2.3.2 for the minor version negotiation. + + Servers SHOULD ignore unknown additions to the ASN.1 types, in + initial requests, where the syntax allows them, except for extensions + to the "Op-req" type, which MUST result in an error. + + Servers MUST respond with an error (ProtocolErrorCode value of + unsupported-minor-version) to clients that use operations unknown to + the server. + +2.8 Protocol Subsets + + The structure of the protocol is such that the ASN.1 syntaxes for the + various operations supported by the protocol are independent of the + each other. Client and server implementations MAY implement subsets + of the overall protocol by removing some alternatives to the Op-req, + Op-rep and Op-err CHOICEs from the ASN.1 module given in section 4. + + For example, it should be possible to have a password-change only + client that cannot set principal's keys - and vice versa. + +3 Protocol Elements + + The protocol as defined herein supports the following operations + relating to the management of Kerberos principal's passwords or keys: + + [NOTE: New since last version of this I-D.] + - get principal's current and preferred string-to-key parameters + + - change password (or enctypes and string-to-key parameters) + - set password (administrative) + - set new keys + - generate new keys + - get new, un-committed keys + - commit new keys + - get password policy name and/or description of principal + - list aliases of a principal + - list enctypes and version of Kerberos V supported by realm + + The operation for retrieving a list of aliases of a principal is + needed where KDCs implement aliasing of principal names and allows + clients to properly setup their key databases when principal aliasing + is in use. + + Operations such as creation or deletion of principals are outside the + scope of this document, and should be performed via other means, such + as through directories or other Kerberos administration protocols. + + The individual operations are described in section 3.2. + +N. Williams et. al. [Page 7] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + +3.1 PDUs + + The types "Request," "Response" and "Error-Response" are the ASN.1 + module's PDUs. + + The "Request" and "Response" PDUs are always to be sent wrapped in + KRB-PRIV messages, except for the "Error-Response" PDU which MUST be + sent as KRB-ERROR e-data (see section 2.4.1) when AP exchanges fail, + otherwise it MUST be sent wrapped in a KRB-PRIV. + + The ASN.1 syntax for the PDUs is given in section 4. + + Note that the first field of each PDU is the major version of the + protocol, defaulted to 2, meaning that it is never included in + version 2 exchanges. Similarly, the second field of each PDU is the + minor version, defaulted to 0. + + The request, responses and error PDUs consist of an outer structure + ("Request," "Response" and "Error-Response") containing fields common + to all requests, responses and errors, respectively, and an inner + structure for fields that are specific to each operation's + requests/responses. The inner structure is optional in the case of + the Error-Response PDU and need not be included when generic errors + occur for which there is a suitable ProtocolErrorCode. + + Specifically, the outer Request structure has a field for passing a + client user's spoken (read) languages to the server. It also has two + optional fields for identifying the requested operation's target + principal's name and realm (if not sent then the server MUST use the + client's principal name and realm as the target). A boolean field + for indicating whether or not the request should be dry-run is also + included; dry-runs can be used to test server policies, and servers + MUST NOT modify any principals when processing dry-run requests. + + The Response and Error PDUs' outer structures include a field + indicating the language that the server has chosen for localization + of text intended to be displayed to users; this field is defaulted to + "i-default". This language tag applies to all UTF8 strings in the + inner structure (Op-rep and Op-err) that are meant to be displayed to + users. + + The protocol error codes are: + + - proto-generic-error + + An operation-specific error ocurred, see the inner Op-error. + + - proto-format-error + - proto-unsupported-major-version + - proto-unsupported-minor-version + - proto-unsupported-operation + + +N. Williams et. al. [Page 8] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + - proto-wrong-service-principal + + Use kadmin/setpw for the server's principal name. + + - proto-re-authentication-required + + The server demands that the client re-authenticate through a new + AP exchange. + + - proto-initial-ticket-required + + Use of an INITIAL ticket is required for the requested + operation. + + - proto-client-and-target-realm-mismatch + + The server requires that the client's principal name and the + target principal of the operation share the same realm name. + + - proto-target-principal-unknown + - proto-authorization-failed + +3.2 Operations + + This section describes the semantics of each operation request and + response defined in the ASN.1 module in section 4. + +3.2.1 Null + + NAME + + null - Null or "ping" operation + + DESCRIPTION + + The null request is intended for use with TCP; its purpose is + similar to RPC null procedures and is akin to a "ping" operation. + + ERRORS + + None. + +3.2.2 Change Kerberos Password + + NAME + + change-pw - Change password operation + + SYNOPSIS + + Req-change-pw(old-pw, [languages], [new-pw], + [commit], [etypes]) -> + Rep-change-pw([info-text], [new-pw], [etypes]) | + +N. Williams et. al. [Page 9] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + Err-change-pw([help-text], error code, [error info]) + + DESCRIPTION + + Change a principal's password. + + The change password request has one required, three optional and + one defaulted arguments: "old-pw" (required), "languages," + "new-pw", "commit" (defaults to "TRUE") and "etypes", + corresponding to the target principal's old password, its + preferred languages, its new password, a boolean indicating + whether or not to make the new long-term key available for + immediate use, and the desired enctypes for the new long-term + keys. + + The server MUST validate the old password and MUST check the + quality of the new password, if sent, according the password + quality policy associated with the target principal. + + If the old and new passwords in the request are the same strings, + and the principal is not currently required to change its + password, then the server MAY permit the password change as way to + change a principal's enctypes and string-to-key parameters. This + feature provides a way to, for example, add enctypes to a + principals' password-derived long-term keys without forcing a + password change following an upgrade to the KDC that adds support + for new enctypes. + + A client MAY request that the server generate a new password by + excluding the new password from its request, in which case the + server MUST either generate a new password or respond with an + error indicating that it does not support this feature. + + Server-generated passwords MUST meet the target principal's + password quality policy. It is RECOMMENDED that server-generated + passwords be user-friendly, that is, memorable and that the target + principal's preferred languages be taken into account by the + password generation alogrithm used by the server. + + Uncommitted password changes are commited using the commit-keys + operation. + + RETURN + + Upon successful password changes the server responds with a + Rep-change-pw. The fields of Rep-change-pw are all optional and + include: + + - 'info-text' which the server can use to send a message to the + user such as "Your new password will expire in 90 days," for + example. + + - 'new-pw' which the server MUST include if the client + +N. Williams et. al. [Page 10] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + requested that the server generate a new password; generated + passwords MUST pass the target principal's password quality + policy. + + - 'etypes' which the server MAY include to indicate which types + of long-term keys it created for the target principal and + which the server MUST include if the client specified a set + of enctypes in its request. + + ERRORS + + The server may respond to change password requests with protocol + or operation errors. See section 3.1 for a description of + protocol error codes. + + All operation errors include an optional 'help-text' field by + which the server can describe the error in a human-readable, + localizaed string. + + Change password error codes include: + + - generic-error + + - old-pw-incorrect + + - wont-generate-new-pw + + The server will not generate a new password for this + principal or does not support password generation in general. + + - new-pw-rejected-generic + + The client's proposed new password failed the target + principal's password quality policy. + + The server MUST include a description of the password quality + policy or aspect of it that the client's proposed new + password failed to meet. + + The server MAY generate and send a new password that the + client can then use as a new password and which is guaranteed + to pass the target principal's current password quality + policy. + + The server MAY include a set of policy error code hints. + + - etype-not-supported + + The client requested an enctype that the KDC does not + support. + +3.2.3 Set Kerberos Password + + +N. Williams et. al. [Page 11] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + NAME + + set-pw - Set password operation + + SYNOPSIS + + Req-set-pw([languages], [new-pw], [commit], [etypes]) -> + Rep-set-pw([info-text], [new-pw], [etypes]) | + Err-set-pw([help-text], error code, [error info]) + + DESCRIPTION + + Administratively set a principal's password. + + The set password request has three optional and one defaulted + arguments: "languages", "new-pw," "commit" (defaulted to "TRUE") + and "etypes", corresponding to the target principal's preferred + languages, new password, a boolean indicating whether or not to + make the new long-term key available for immediate use, and the + desired enctypes for the new long-term keys. + + The server MUST check the quality of the new password, if sent, + according the password quality policy associated with the target + principal. + + The server SHOULD require that the client use the change-pw + operation instead of set-pw when the client principal and the + target principal are the same. + + A client MAY request that the server generate a new password by + excluding the new password from its request, in which case the + server MUST either generate a new password or respond with an + error indicating that it does not support this feature. + + Server-generated passwords MUST meet the target principal's + password quality policy. It is RECOMMENDED that server-generated + passwords be user-friendly, that is, memorable and that the target + principal's preferred languages be taken into account by the + password generation alogrithm used by the server. + + RETURN + + Upon successfully setting a password the server responds with a + Rep-set-pw. The fields of Rep-set-pw are all optional and + include: + + - 'info-text' which the server can use to send a message to the + user such as "Your new password will expire in 90 days," for + example. + + - 'new-pw' which the server MUST include if the client + requested that the server generate a new password; generated + passwords MUST pass the target principal's password quality + +N. Williams et. al. [Page 12] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + policy. + + - 'etypes' which the server MAY include to indicate which types + of long-term keys it created for the target principal and + which the server MUST include if the client specified a set + of enctypes in its request. + + ERRORS + + The server may respond to set password requests with protocol or + operation errors. See section XYZ for a description of protocol + error codes. + + All operation errors include an optional 'help-text' field by + which the server can describe the error in a human-readable, + localizaed string. + + Set password error codes include: + + - generic-error + + - use-change-pw + + The server demands that the client use the change-pw + operation for the target principal of the set-pw request. + + - wont-generate-new-pw + + The server will not generate a new password for this + principal or does not support password generation in general. + + - new-pw-rejected-generic + + The client's proposed new password failed the target + principal's password quality policy. + + The server MUST include a description of the password quality + policy or aspect of it that the client's proposed new + password failed to meet. + + The server MAY generate and send a new password that the + client can then use as a new password and which is guaranteed + to pass the target principal's current password quality + policy. + + The server MAY include a set of policy error code hints. + + - etype-not-supported + + The client requested an enctype that the KDC does not + support. + +3.2.4 Set Kerberos Keys + +N. Williams et. al. [Page 13] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + + NAME + + set-keys + + SYNOPSIS + + Req-set-keys(new-keys, commit?, [isupport]) -> + Rep-set-keys([info-text], kvno, aliases, [isupport]) + + DESCRIPTION + + The set-keys request consists of two required fields and one + optional field: "new-keys", "commit" (a boolean field - see below) + and "isupport", an optional field for indicating to the KDC what + Kerberos V features are supported by the target principal. + + When "commit" is true the KDC makes the new keys available for + issueing tickets encrypted in them immediately. Otherwise the + client MUST follow up with a commit-keys request to make the keys + available. This feature is useful for changing keys shared by + multiple hosts, in clustered services, for example, in an atomic + manner; see section 3.2.6 and 3.2.7. + + If a principal has keys are awaiting commitment when a new + set-keys request for that principal s made then the KDC MUST + overwrite the deferred keys. + + RETURN + + For successful set-keys operations the server returns: + + - Informational text, optional. + + - The new kvno for the target principal. + + - A list of aliases of the target principal known to the KDC + (optional). + + - The set of Kerberos V features supported by the KDC + (optional). + + ERRORS + + The server may respond with the following errors: + + - generic + - deferred-commit-no-support + - etype-no-support + +3.2.5 Generate Kerberos Keys + + NAME + +N. Williams et. al. [Page 14] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + + gen-keys + + SYNOPSIS + + Req-gen-keys(etypes, [entropy], commit?, [isupport]) -> + Rep-set-keys([info-text], key, kvno, aliases, [isupport]) + + DESCRIPTION + + The gen-keys is similar to the set-keys request (see section + 3.2.4) but differs in that the server generates keys of + client-requested enctypes, rather than the client providing + specific keys. + + The gen-keys request consists of two required fields and two + optional fields: "etypes" (the enctypes of the new keys), + "entropy", "commit" and "isupport" (see section 3.2.4). + + If a principal has keys are awaiting commitment when a new + set-keys request for that principal s made then the KDC MUST + overwrite the deferred keys. + + RETURN + + For successful set-keys operations the server returns: + + - Informational text, optional. + + - The new kvno for the target principal. + + - The new key (only one is needed). + + - A list of aliases of the target principal known to the KDC + (optional). + + - The set of Kerberos V features supported by the KDC + (optional). + + ERRORS + + The server may respond with the following errors: + + - generic + - deferred-commit-no-support + - etype-no-support + +3.2.6 Get New Keys + + NAME + + get-keys + + +N. Williams et. al. [Page 15] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + SYNOPSIS + + Req-get-keys(kvno) -> + Rep-get-keys([info-text], keys, aliases, [isupport]) | + Err-get-keys([help-text], error code, [error info]) + + DESCRIPTION + + This request allows a client to get the keys set or generated in a + previous set-keys or gen-keys request with deferred commitment.. + + RETURN + + If the target principal and kvno correspond to uncommitted keys + the server MUST respond with the actual keys that would be set by + a subsequent commit-keys request. Otherwise the server MUST + respond with an error (meaning that this operation cannot be used + to extract keys from the KDC that may be in use). + + ERRORS + + - generic + - kvno-committed + - no-such-kvno + +3.2.7 Commit New Keys + + NAME + + commit-keys + + SYNOPSIS + + Req-commit-keys(kvno) -> + Rep-commit-keys() | + Err-commit-keys([help-text], error code, [error info]) + + DESCRIPTION + + The commit-keys operation allows a client to bring a principal's + new keys into use at the KDC. + + Clients should make a commit-keys request corresponding to a + deferred commitment set-keys/gen-keys operation as soon as the + local key database for the target principal is updated. + + The target principal name and the kvno MUST match those from a + prior set-keys or gen-keys operation. + + Servers MAY expire delayed key commitments at will. Servers + SHOULD expire uncommitted new keys after a reasonable amount of + time (600 seconds is RECOMMENDED). + + +N. Williams et. al. [Page 16] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + Servers MUST respond to new set-keys requests for principals with + pending, uncommitted new keys by expiring the uncommitted new keys + and proceeding as if there had been no expired new keys. + + ERRORS + + - generic + - op-kvno-expired + - op-kvno-unknown + - new-keys-conflict (A set-keys or gen-keys request succeeded + subsequent to the request that matches this + {principal, kvno} tuple.) + +3.2.8 Get Password Quality Policy + + NAME + + get-pw-policy + + SYNOPSIS + + Req-get-pw-policy() -> + Rep-get-pw-policy([policy name], [policy description]) + + DESCRIPTION + + Returns a description of the target principal's associated + password quality policy, if any, as a list of localized + UTF8String values. + + Clients can use this operation in conjunction with the change-pw + operation to obtain text that can be displayed to the user before + the user actually enters a new password. + + It is common for sites to set policies with respect to password + quality. It is beyond the scope of this document to describe such + policies. Management of password quality policies' actual content + is also beyond the scope of this protocol. + + ERRORS + + No operation errors are defined. + + +3.2.9 Get Principal Aliases + + NAME + + get-print-aliases + + SYNOPSIS + + Req-get-princ-aliases() -> + +N. Williams et. al. [Page 17] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + Rep-get-princ-aliases(aliases) + + DESCRIPTION + + Returns a list of aliases of the target principal. + + ERRORS + + No operation-specific errors. + +3.2.10 Get Realm's Supported Kerberos V Version and Features + + NAME + + get-realm-krb5-support + + SYNOPSIS + + Req-get-realm-krb5-support() -> + Rep-get-realm-krb5-support(isupport) + + DESCRIPTION + + Returns set of Kerberos V features support by the target + principal's realm's KDCs. + + ERRORS + + No operation-specific errors. + +3.2.11 Retrieve Principal's S2K Params and Preferred Params + + NAME + + get-s2kparams + + SYNOPSIS + + Req-get-s2kparams() -> + Rep-get-s2kparams([princ-s2kparams], [preferred-s2kparams]) + + DESCRIPTION + + Returns the string2key parameters for the principal's current + password-derived long-term keys, if any, and the parameters that + the realm would prefer, if they differ from the former. + + This operation is intended for use with the change-pw() operation. + When surprised by a KDC's PA-ETYPE-INFO2 a client SHOULD check if + the principal's long-term secret keys' string2key parameters (and + enctype list) should be changed and, if so, change them. + + If the 'princ-s2kparams' return value is missing then the + +N. Williams et. al. [Page 18] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + principal does not have a password-derived long-term key. + + The 'preferred-s2kparams' MUST be excluded if the principal's + string2key parameters satisfy the realm's policy. + + ERRORS + + No operation-specific errors. + +3.3 Principal Aliases + + Applications that use Kerberos often have to derive acceptor + principal names from hostnames entered by users. Such hostnames may + be aliases, they may be fully qualified, partially qualified or not + qualified at all. Some implementations have resorted to deriving + principal names from such hostnames by utilizing the names services + to canonicalize the hostname first; such practices are not secure + unless the name service are secure, which often aren't. + + One method for securely deriving principal names from hostnames is to + alias principals at the KDC such that the KDC will issue tickets for + principal names which are aliases of others. It is helpful for + principals to know what are their aliases as known by the KDCs. + + Note that changing a principal's aliases is out of scope for this + protocol. + +3.4 Kerberos V Feature Negotiation + + Principals and realms' KDCs may need to know about additional + Kerberos V features and extensions that they each support. Several + operations (see above) provide a way for clients and servers to + exchange such infomration, in the form of lists of types supported + for the various typed holes used in Kerberos V. + +4 ASN.1 Module + + DEFINITIONS EXPLICIT TAGS ::= BEGIN + -- + -- Note: EXPLICIT tagging is in use by default throughout this + -- module. + + -- From [clarifications] with modifications + PrincipalName ::= SEQUENCE { + name-string [1] SEQUENCE OF UTF8String (IA5String, ...) + } + Realm ::= UTF8String (IA5String, ...) + Salt ::= UTF8String (IA5String, ...) + Password ::= UTF8String (IA5String, ...) + + -- NOTE WELL: Principal and realm names MUST be constrained by the + -- specification of the version of Kerberos V used by the + -- client. + +N. Williams et. al. [Page 19] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + -- + -- [Perhaps PrincipalName should be a SEQUENCE of an optional name + -- type and a UTF8String, for simplicity.] + + -- From [clarifications] + Int32 ::= INTEGER (-2147483648..2147483647) + UInt32 ::= INTEGER (0..4294967295) + + -- Based on [clarifications] + Etype ::= Int32 + Etype-Info-Entry ::= SEQUENCE { + etype [0] Etype, + salt [1] Salt OPTIONAL, + s2kparams [2] OCTET STRING OPTIONAL, + ... + } + Key ::= SEQUENCE { + enc-type [0] Etype, -- from Kerberos + key [1] OCTET STRING, + ... + } + + Language-Tag ::= UTF8String -- Constrained by [RFC3066] + + -- Empty, extensible SEQUENCEs are legal ASN.1 + Extensible-NULL ::= SEQUENCE { + ... + } + + -- Kerberos clients negotiate some parameters relating to their peers + -- indirectly through the KDC. Today this is true of ticket session + -- key enctypes, but in the future this indirect negotiation may also + -- occur with respect to the minor version of Kerberos V to be used + -- between clients and servers. Additionally, KDCs may need to know + -- what authorization-data types are supported by service principals, + -- both, for compatibility with legacy software and for optimization. + -- + -- Thesefore it is important for KDCs to know what features of + -- Kerberos V each service principal supports. + -- + -- In version 2.0 of this protocol the clients and servers may notify + -- each other of their support for: + -- + -- - enctypes + -- - authorization data types + -- - transited encoding data types + -- + -- All authorization-data types defined in [clarifications] are + -- assumed to be supported if the minor version is 1 and do not need + -- to be included in the ad-type list. + -- + -- Int32 is used for enctype and transited encoding data type + -- identifiers. + +N. Williams et. al. [Page 20] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + -- + -- An extensible CHOICE of Int32 is used for authorization data + -- types. + + KerberosV-TR-ID ::= Int32 + + KerberosV-AD-ID ::= CHOICE { + ad-int [0] Int32, + ... + } + + KerberosVSupportNego ::= SEQUENCE { + enc-types [0] SEQUENCE OF Etype, + ad-types [1] SEQUENCE OF KerberosV-AD-ID OPTIONAL, + -- authorization data types + tr-enc-types [2] SEQUENCE OF KerberosV-TR-ID OPTIONAL, + -- transited encoding types + ... + } + + Request ::= [APPLICATION 0] SEQUENCE { + pvno-minor [0] INTEGER DEFAULT 0, + languages [1] SEQUENCE OF Language-Tag OPTIONAL, + -- Should be defaulted to the SEQUENCE of "i-default" + targ-name [2] PrincipalName OPTIONAL, + targ-realm [3] Realm OPTIONAL, + -- If targ-name/realm are missing then the request + -- applies to the principal of the client + dry-run [4] BOOLEAN DEFAULT FALSE, + operation [5] Op-req, + ... + } + + Response ::= [APPLICATION 1] SEQUENCE { + pvno-minor [0] INTEGER DEFAULT 0, + language [1] Language-Tag DEFAULT "i-default", + result [2] Op-rep, + ... + } + + Error-Response ::= [APPLICATION 2] SEQUENCE { + pvno-minor [0] INTEGER DEFAULT 0, + language [1] Language-Tag DEFAULT "i-default", + error-code [2] ProtocolErrorCode, + help-text [3] UTF8String OPTIONAL, + op-error [4] Op-err OPTIONAL, + ... + } + + Op-req ::= CHOICE { + null [0] Req-null, + change-pw [1] Req-change-pw, + set-pw [2] Req-set-pw, + +N. Williams et. al. [Page 21] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + set-keys [3] Req-set-keys, + gen-keys [4] Req-gen-keys, + get-keys [5] Req-get-keys, + commit-keys [6] Req-commit-keys, + get-pw-policy [7] Req-get-pw-policy, + get-princ-aliases [8] Req-get-princ-aliases, + get-realm-krb5-support [9] Req-get-realm-krb5-support, + get-s2kparams [10] Req-get-s2kparams, + ... + } + + Op-rep ::= CHOICE { + null [0] Rep-null, + change-pw [1] Rep-change-pw, + set-pw [2] Rep-set-pw, + set-keys [3] Rep-set-keys, + gen-keys [4] Req-gen-keys, + get-keys [5] Req-get-keys, + commit-keys [6] Rep-commit-keys, + get-pw-policy [7] Rep-get-pw-policy, + get-princ-aliases [8] Rep-get-princ-aliases, + get-realm-krb5-support [9] Rep-get-realm-krb5-support, + get-s2kparams [10] Rep-get-s2kparams, + ... + } + + Op-err ::= CHOICE { + null [0] Err-null, + change-pw [1] Err-change-pw, + set-pw [2] Err-set-pw, + set-keys [3] Err-set-keys, + gen-keys [4] Err-gen-keys, + get-keys [5] Err-get-keys, + commit-keys [6] Err-commit-keys, + get-pw-policy [7] Err-get-pw-policy, + get-princ-aliases [8] Err-get-princ-aliases, + get-realm-krb5-support [9] Err-get-realm-krb5-support, + get-s2kparams [10] Err-get-s2kparams, + ... + } + + ProtocolErrorCode ::= ENUM { + proto-format-error, + proto-unsupported-major-version, + proto-unsupported-minor-version, + proto-unsupported-operation, -- Request CHOICE tag unknown + proto-generic-see-op-error, -- See Op-error + proto-wrong-service-principal, -- Use kadmin/setpw + proto-re-authentication-required, + proto-initial-ticket-required, + proto-client-and-target-realm-mismatch, + proto-target-principal-unknown, + proto-authorization-failed, + +N. Williams et. al. [Page 22] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + proto-dry-run-not-permitted, + ... + } + + -- These codes are hints for clients, primarily for when they are + -- used for changing the passwords of automated principals; error + -- replies carry password quality policy help text that is more + -- appropriate for clients to display to users. + PW-Quality-Codes ::= ENUM { + pwq-generic, + pwq-too-soon, + pwq-repeated, + pwq-too-short, + pwq-dictionary-words, + pwq-prohibited-codepoints, + pwq-need-more-char-classes, + ... + } + + -- + -- Requests and responses + -- + + -- NULL request, much like ONC RPC's NULL procedure - NOT extensible + Req-null ::= NULL + + Rep-null ::= NULL + + Err-null ::= NULL + + -- Change password + Req-change-pw ::= SEQUENCE { + old-pw [0] Password, + new-pw [1] Password OPTIONAL, + commit [2] BOOLEAN DEFAULT TRUE, + etypes [3] SEQUENCE (1..) OF Etype OPTIONAL, + ... + } + + Rep-change-pw ::= SEQUENCE { + info-text [0] UTF8String OPTIONAL, + new-pw [1] Password OPTIONAL, + -- generated by the server if present + -- (and requested by the client) + etypes [2] SEQUENCE (1..) OF Etype OPTIONAL, + ... + } + + Err-change-pw ::= SEQUENCE { + help-text [0] UTF8String OPTIONAL, + error [1] CHOICE { + op-generic-error [0] Extensible-NULL, + op-old-pw-incorrect [1] Extensible-NULL, + +N. Williams et. al. [Page 23] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + op-wont-generate-new-pw [2] Extensible-NULL, + op-new-pw-rejected-generic [3] SEQUENCE { + policy [1] SEQUENCE OF UTF8String, + suggested-pw [2] Password OPTIONAL, + policy-codes [3] SET OF PW-Quality-Codes + OPTIONAL, + ... + } + op-etype-not-supported [4] SEQUENCE { + supported-etypes [1] SEQUENCE OF Etype, + ... + }, + ... + }, + ... + } + + -- Set password + Req-set-pw ::= SEQUENCE { + languages [0] SEQUENCE OF Language-Tag OPTIONAL, + new-pw [1] Password OPTIONAL, + commit [2] BOOLEAN DEFAULT TRUE, + etypes [3] SEQUENCE (1..) OF Etype OPTIONAL, + ... + } + + Rep-set-pw ::= SEQUENCE { + info-text [0] UTF8String OPTIONAL, + new-pw [1] Password OPTIONAL, + -- generated by the server if present + -- (and requested by the client) + etypes [2] SEQUENCE (1..) OF Etype OPTIONAL, + ... + } + + Err-set-pw ::= Err-change-pw + + -- Set keys + Req-set-keys ::= SEQUENCE { + keys [0] SEQUENCE OF Key, + commit [1] BOOLEAN DEFAULT TRUE, + -- TRUE -> install keys now + -- + -- FALSE -> require set-keys-commit + -- before issuing tickets + -- encrypted with these keys. + -- + -- See commit-keys op + isupport [2] KerberosVSupportNego OPTIONAL, + -- For future Kerberos V extensions KDCs + -- may need to know what krb5 version is + -- supported by individual service + -- principals. This field provides a + +N. Williams et. al. [Page 24] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + -- way to tell the KDC what version of + -- Kerberos V the target principal + -- supports. + ... + } + + Rep-set-keys ::= SEQUENCE { + info-text [0] UTF8String OPTIONAL, + kvno [1] UInt32, + aliases [2] SEQUENCE OF SEQUENCE { + name [0] PrincipalName, + realm [1] Realm OPTIONAL, + ... + }, + isupport [3] KerberosVSupportNego OPTIONAL, + ... + -- Should there be ETYPE-INFO2 stuff here? + } + + Err-set-keys ::= SEQUENCE { + help-text [0] UTF8String OPTIONAL, -- Reason for rejection + error [1] CHOICE { + op-generic [0] Extensible-NULL, + op-deferred-commit-no-support [1] Extensible-NULL, + op-etype-no-support [2] SEQUENCE OF { + supported-etypes [1] SEQUENCE OF Etype, + ... + } + ... + } + } + + -- Generate keys + Req-gen-keys ::= SEQUENCE { + etypes [0] SEQUENCE (1..) OF Etype, + entropy [1] OCTET STRING OPTIONAL, + commit [2] BOOLEAN DEFAULT TRUE, + -- TRUE -> install keys now + -- + -- FALSE -> require set-keys-commit + -- before issuing tickets + -- encrypted with these keys. + -- + -- See commit-keys op + isupport [3] KerberosVSupportNego OPTIONAL, + -- For future Kerberos V extensions KDCs + -- may need to know what krb5 version is + -- supported by individual service + -- principals. This field provides a + -- way to tell the KDC what version of + -- Kerberos V the target principal + -- supports. + ... + +N. Williams et. al. [Page 25] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + } + + Rep-gen-keys ::= SEQUENCE { + info-text [0] UTF8String OPTIONAL, + kvno [1] UInt32, + key [2] Key, + aliases [3] SEQUENCE OF SEQUENCE { + name [0] PrincipalName, + realm [1] Realm OPTIONAL, + ... + }, + isupport [4] KerberosVSupportNego OPTIONAL, + ... + -- Should there be ETYPE-INFO2 stuff here? + } + + Err-gen-keys ::= Err-set-keys + + -- Get un-committed key request + Req-get-keys ::= SEQUENCE { + kvno [0] UInt32, + ... + } + + Rep-get-keys ::= SEQUENCE { + info-text [0] UTF8String OPTIONAL, + keys [1] SEQUENCE OF Key, + aliases [2] SEQUENCE OF SEQUENCE { + name [0] PrincipalName, + realm [1] Realm OPTIONAL, + ... + }, + isupport [3] KerberosVSupportNego OPTIONAL, + ... + -- Should there be ETYPE-INFO2 stuff here? + } + + Err-get-keys ::= SEQUENCE { + help-text [0] UTF8String OPTIONAL, -- Reason for rejection + error [1] CHOICE { + op-generic [0] Extensible-NULL, + op-kvno-committed [1] Extensible-NULL, + op-no-such-kvno [1] Extensible-NULL, + ... + } + } + + -- Commit a set keys request + Req-commit-keys ::= SEQUENCE { + kvno [0] UInt32, + ... + } + + +N. Williams et. al. [Page 26] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + Rep-commit-keys ::= Extensible-NULL + + Err-commit-keys ::= SEQUENCE { + help-text [0] UTF8String OPTIONAL, -- Reason for rejection + error [1] CHOICE { + op-generic [0] Extensible-NULL, + op-kvno-expired [1] Extensible-NULL, + -- The client took too long to respond. + op-kvno-unknown [2] Extensible-NULL, + -- The targ princ/kvno is invalid or unknown to the + -- server (perhaps it lost track of state) + op-new-keys-conflict [3] Extensible-NULL, + -- A new-keys/commit-keys request subsequent to the + -- new-keys that produced the kvno has completed + -- and incremented the principal's kvno + ... + } + ... + } + + -- Get password policy + Req-get-pw-policy ::= Extensible-NULL + + Rep-get-pw-policy ::= SEQUENCE { + policy-name [0] UTF8String OPTIONAL, + description [1] SEQUENCE OF UTF8String OPTIONAL, + ... + } + + Err-get-pw-policy ::= Extensible-NULL + + -- Get principal aliases + Req-get-princ-aliases ::= Extensible-NULL + + Rep-get-princ-aliases ::= SEQUENCE { + help-text [0] UTF8String OPTIONAL, + aliases [1] SEQUENCE OF SEQUENCE { + name [0] PrincipalName, + realm [1] Realm OPTIONAL, + ... + }, + ... + } + + Err-get-princ-aliases ::= Extensible-NULL + + -- Get list of enctypes supported by KDC for new keys + Req-get-realm-krb5-support ::= Extensible-NULL + + Rep-get-realm-krb5-support ::= SEQUENCE { + isupport [0] KerberosVSupportNego, + -- Version of Kerberos V supported by + -- the target realm. + +N. Williams et. al. [Page 27] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + ... + } + + Err-get-realm-krb5-support ::= Extensible-NULL + + -- Get s2kparams + Req-get-s2kparams ::= Extensible-NULL + + Rep-get-s2kparams ::= SEQUENCE { + help-text [0] UTF8String OPTIONAL, + s2kparams [1] SEQUENCE OF Etype-Info-Entry, + ... + } + + Err-get-s2kparams ::= Extensible-NULL + + END + + +6 IANA Considerations + + There are no IANA considerations for this document. + +7 Security Considerations + + Implementors and site administrators should note that the redundancy + of UTF-8 encodings of passwords varies by language. Password quality + policies SHOULD, therefore, take this into account when estimating + the amount of redundancy and entropy in a proposed new password. [?? + It's late at night - I think this is correct.] + + Kerberos set/change password/key protocol major version negotiation + cannot be done securely; a downgrade attack is possible against + clients that attempt to negotiate the protocol major version to use + with a server. It is not clear at this time that the attacker would + gain much from such a downgrade attack other than denial of service + (DoS) by forcing the client to use a protocol version which does not + support some feature needed by the client (Kerberos V in general is + subject to a variety of DoS attacks anyways [RFC1510]). Clients + SHOULD NOT negotiate support for legacy major versions of this + protocol unless configured otherwise. + + This protocol does not have Perfect Forward Security (PFS). As a + result, any passive network snooper watching password/key changing + operations who has stolen a principal's password or long-term keys + can find out what the new ones are. + + [More text needed?] + +8 Acknowledgements + + The authors would like to thank Bill GossmanMike Swift, John Brezak, + Ken Raeburn, Tom Yu, Martin Rex, Sam Hartman, Tony Andrea, Paul W. + +N. Williams et. al. [Page 28] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + Nelson, Marcus Watts, Love, Joel N. Weber II, Jeffrey Hutzelman and + other participants from the IETF Kerberos Working Group for their + assistance. + +9 References + +9.1 Normative References + + [RFC2026] + S. Bradner, RFC2026: "The Internet Standard Process - Revision + 3," October 1996, Obsoletes - RFC 1602, Status: Best Current + Practice. + + [RFC2119] + S. Bradner, RFC2119 (BCP14): "Key words for use in RFCs to + Indicate Requirement Levels," March 1997, Status: Best Current + Practice. + + [X680] + Abstract Syntax Notation One (ASN.1): Specification of Basic + Notation, ITU-T Recommendation X.680 (1997) | ISO/IEC + International Standard 8824-1:1998. + http://www.itu.int/ITU-T/studygroups/com17/languages/X680_0702.pdf + + [X690] + ASN.1 encoding rules: Specification of Basic Encoding Rules (BER), + Canonical Encoding Rules (CER) and Distinguished Encoding Rules + (DER), ITU-T Recommendation X.690 (1997)| ISO/IEC International + Standard 8825-1:1998. + http://www.itu.int/ITU-T/studygroups/com17/languages/X690_0702.pdf + + [clarifications] + RFC-Editor: To be replaced by RFC number for + draft-ietf-krb-wg-kerberos-clarifications. + + [RFC3066] + H. Alvestrand, RFC3066 (BCP47): "Tags for the Identification of + Languages," January 2001, Obsoletes RFC1766, Status: Best Current + Practice. + +9.2 Informative References + + [RFC3244] + M. Swift, J. Trostle, J. Brezak, RFC3244: "Microsoft Windows 2000 + Kerberos Change Password and Set Password Protocols," February + 2002, Status: Informational. + +10 Authors' Addresses + + Nicolas Williams + Sun Microsystems + 5300 Riata Trace Ct + Austin, TX 78727 + +N. Williams et. al. [Page 29] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + Email: nicolas.williams@sun.com + + Jonathan Trostle + Cisco Systems + 170 W. Tasman Dr. + San Jose, CA 95134 + Email: jtrostle@cisco.com + +11 Notes to the RFC Editor + + This document has two KRB WG drafts as normative references and + cannot progress until those drafts progress, but no other draft + depends on this one. + +12 Change History + + -01 -> -02 + + - Removed Bill Gossman, Mike Swift and John Brezak as authors. + + - Removed UDP as a transport for this protocol. + + - Replaced redundant copies of framing ASCII art with reference to + RFC3244. + + - Made all name/password strings UTF8String with an extensible + constraint to IA5String. + + - Added a method for doing dry runs of operations. This is helpful + in testing passwords against password quality policies. + + - Added an operation for retrieving a principal's current and + preferred string-to-key parameters, and a way to change them + without changing the principal's password. + + - Added password quality codes as hints for smart clients, but + these are optional and not to be used instead of messages to be + displayed to useds. + + - Added a 'commit' option to change-pw and set-pw (as requested by + Larry). + + - Removed "version" field of the Kerberos V feature negotiation + struture. + + + +N. Williams et. al. [Page 30] + +DRAFT Kerberos Set/Change Password v2 Expires January 2005 + + + +Intellectual Property Statement + + The IETF takes no position regarding the validity or scope of any + Intellectual Property Rights 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; nor does it represent that it has + made any independent effort to identify any such rights. Information + on the procedures with respect to rights in RFC documents can be + found in BCP 78 and BCP 79. + + Copies of IPR disclosures made to the IETF Secretariat 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 implementers or users of this + specification can be obtained from the IETF on-line IPR repository at + http://www.ietf.org/ipr. + + The IETF invites any interested party to bring to its attention any + copyrights, patents or patent applications, or other proprietary + rights that may cover technology that may be required to implement + this standard. Please address the information to the IETF at + ietf-ipr@ietf.org. + + +Disclaimer of Validity + + This document and the information contained herein are provided on an + "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS + OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET + ENGINEERING TASK FORCE DISCLAIM 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. + + +Copyright Statement + + Copyright (C) The Internet Society (2004). This document is subject + to the rights, licenses and restrictions contained in BCP 78, and + except as set forth therein, the authors retain all their rights. + +Acknowledgment + + Funding for the RFC Editor function is currently provided by the + Internet Society. + + + + + + + + +N. Williams et. al. [Page 31] + |