Kerberos, PACs And Microsoft's Dirty Tricks

Chris DiBona wrote to us with something that Ted and Jeremy (Samba Boys) wrote: "Microsoft, after getting beat up in the press for making propietary extensions to the Kerberos protocol, has released the specifications on the web -- but in order to get it, you have to run a Windows .exe file which forces you agree to a click-through license agreement where you agree to treat it as a trade secret, before it will give you the .pdf file. Who would have thought that you could publish a trade secret on the web?" Read more from the Samba Team below.

The critical part of the license states:

• "b. The Specification is confidential information and a trade secret of Microsoft. Therefore, you may not disclose the Specification to anyone else (except as specifically allowed below), and you must take reasonable security precautions, at least as great as the precautions you take to protect your own confidential information, to keep the Specification confidential. If you are an entity, you may disclose the Specification to your full-time employees on a need to know basis, provided that you have executed appropriate written agreements with your employees sufficient to enable you to comply with the terms of this Agreement.

This is course is a very clever way to pretend to distribute the spec, whilst making it completely impossible to implement in competiting implementations which implements their propietary protocol extensions --- extensions to a protocol which was originally published by the Kerberos team as an Open Standard in the IETF. This completely defeats the IETF's interoperability goals, and helps Microsoft leverge their desktop monopoly into the server market.

The one good thing about Microsoft having pulled this dirty trick is that it makes their propietary intentions about the Windows 2000 PDC clear as day. I doubt anyone else could come up with a charitable explanation for what they've done. What a better example of Microsoft's "embrace, extend, and engulf" business model!

Jeremy Allison,
Samba Team.

Theodore Ts'o,
(former) Kerberos Development Lead "

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© 2000 Microsoft Corporation. All rights reserved. Microsoft Confidential.
This Specification is provided pursuant to the terms and conditions of the Agreement for Microsoft Authorization Data Specification
v. 1.0 for Microsoft Windows 2000 Operating Systems (the "Agreement") for the sole purpose of allowing review of the
Specification for security analysis, as further specified in the Agreement. If you have not downloaded the Specification from
Microsoft's website and agreed to the terms and conditions of the Agreement, you are not an authorized licensee of the Specification.
Page 1 of 12
Microsoft Authorization Data Specification v. 1.0
for Microsoft Windows 2000 Operating Systems
April, 2000
© 2000 Microsoft Corporation.
All rights reserved.
Microsoft Confidential
Please review this Specification copy only if you licensed and downloaded it from Microsoft
Corporation's website; if you did not, please destroy this copy, but you are welcome to license the
Specification at http://www.microsoft.com/technet/security/kerberos .
If you are an authorized licensee, when you downloaded the following Specification, you agreed
to the Agreement for Microsoft Authorization Data Specification v. 1.0 for Microsoft Windows 2000
Operating Systems (the "Agreement"). For your future reference, that Agreement is reproduced at
the end of this document.
Abstract
Microsoft Windows 2000 includes OS specific data in the Kerberos V5 authorization data field that is
used for authorization as described in the Kerberos revisions Internet Draft [1]. This data is used for
user logon and to create an access token. The access token is used by the system to enforce
access checking when attempting to reference objects. This document describes the structure of
the Windows 2000 specific authorization data that is carried in that field.
Top-Level PAC Structure
The PAC is generated by the KDC under the following conditions:
during an AS request that has been validated with pre-authentication
during a TGS request when the client has no PAC and the target is a service in the domain or a
ticket granting service (referral ticket).
The PAC itself is included in the IF-RELEVANT (ID 1) portion of the authorization data in a ticket.
Within the IF-RELEVANT portion, it is encoded as a KERB_AUTH_DATA_PAC with ID 128.
The PAC is defined as a C data type, with integers encoded in little-endian order. The PAC itself is
made up of several layers. The outer structure, contained directly in the authorization data, is as
follows. The top-level structure is the PACTYPE structure:

Windows 2000 Kerberos Authorization Data April 2000
© 2000 Microsoft Corporation. All rights reserved. Microsoft Confidential.
This Specification is provided pursuant to the terms and conditions of the Agreement for Microsoft Authorization Data Specification
v. 1.0 for Microsoft Windows 2000 Operating Systems (the "Agreement") for the sole purpose of allowing review of the
Specification for security analysis, as further specified in the Agreement. If you have not downloaded the Specification from
Microsoft's website and agreed to the terms and conditions of the Agreement, you are not an authorized licensee of the Specification.
Page 2 of 12
typedef unsigned long ULONG;
typedef unsigned short USHORT;
typedef unsigned long64 ULONG64;
typedef unsigned char UCHAR;
typedef struct _PACTYPE {
ULONG cBuffers;
ULONG Version;
PAC_INFO_BUFFER Buffers[1];
} PACTYPE;
The fields are defined as follows:
cBuffers - contains the number of entries in the array Buffers
Version - this is version zero
Buffers - contains a conformant array of PAC_INFO_BUFFER structures
The PAC_INFO_BUFFER structure contains information about each piece of the PAC:
typedef struct _PAC_INFO_BUFFER {
ULONG ulType;
ULONG cbBufferSize;
ULONG64 Offset;
} PAC_INFO_BUFFER;
Type fields are defined as follows:
ulType - contains the type of data contained in this buffer. For Windows 2000, it may be one of the
following, which are explained further below:
#define PAC_LOGON_INFO 1
#define PAC_CREDENTIAL_TYPE 2
#define PAC_SERVER_CHECKSUM 6
#define PAC_PRIVSVR_CHECKSUM 7
#define PAC_CLIENT_INFO_TYPE 10
Offset - contains the offset to the beginning of the data, in bytes, from the beginning of the
PACTYPE structure. The data offset must by a multiple of 8. If the data pointed to by this field is
complex, the data is typically NDR encoded. If the data is simple (indicating it includes no pointer
types or complex structures) it is a little-endian format data structure.

Windows 2000 Kerberos Authorization Data April 2000
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This Specification is provided pursuant to the terms and conditions of the Agreement for Microsoft Authorization Data Specification
v. 1.0 for Microsoft Windows 2000 Operating Systems (the "Agreement") for the sole purpose of allowing review of the
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Page 3 of 12
PAC Credential Information
PAC_INFO_BUFFERs of type PAC_LOGON_INFO contain the credential information for the client of
the Kerberos ticket. The data itself is contained in a KERB_VALIDATION_INFO structure, which is NDR
encoded. The output of the NDR encoding is placed in the PAC_INFO_BUFFER structure of type
PAC_LOGON_INFO.
typedef struct _KERB_VALIDATION_INFO {
FILETIME LogonTime;
FILETIME LogoffTime;
FILETIME KickOffTime;
FILETIME PasswordLastSet;
FILETIME PasswordCanChange;
FILETIME PasswordMustChange;
UNICODE_STRING EffectiveName;
UNICODE_STRING FullName;
UNICODE_STRING LogonScript;
UNICODE_STRING ProfilePath;
UNICODE_STRING HomeDirectory;
UNICODE_STRING HomeDirectoryDrive;
USHORT LogonCount;
USHORT BadPasswordCount;
ULONG UserId;
ULONG PrimaryGroupId;
ULONG GroupCount;
[size_is(GroupCount)] PGROUP_MEMBERSHIP GroupIds;
ULONG UserFlags;
ULONG Reserved[4];
UNICODE_STRING LogonServer;
UNICODE_STRING LogonDomainName;
PSID LogonDomainId;
ULONG Reserved1[2];
ULONG UserAccountControl;
ULONG Reserved3[7];
ULONG SidCount;
[size_is(SidCount)] PKERB_SID_AND_ATTRIBUTES ExtraSids;
PSID ResourceGroupDomainSid;
ULONG ResourceGroupCount;
[size_is(ResourceGroupCount)] PGROUP_MEMBERSHIP ResourceGroupIds;
} KERB_VALIDATION_INFO;
The fields are defined as follows:
LogonTime - the time the client last logged on.

Windows 2000 Kerberos Authorization Data April 2000
© 2000 Microsoft Corporation. All rights reserved. Microsoft Confidential.
This Specification is provided pursuant to the terms and conditions of the Agreement for Microsoft Authorization Data Specification
v. 1.0 for Microsoft Windows 2000 Operating Systems (the "Agreement") for the sole purpose of allowing review of the
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LogoffTime - the time at which the client's logon session should expire. If the logon session should
not expire, this field should be set to (0x7fffffff,0xffffffff).
KickOffTime - the time at which the server should forcibly logoff the client. If the client should not be
forced off, this field should be set to (0x7fffffff,0xffffffff). The ticket end time is a replacement for the
KickOffTime. The service ticket lifetime will never be longer than the KickOffTime for a user.
PasswordLastSet - the time the client's password was last set. If it was never set, this field is zero.
PasswordCanChange - the time at which the client's password is allowed to change. If there is no
restriction on when the client may change its password, this field should be set to the time of the
logon.
PasswordMustChange - the time at which the client's password expires. If it doesn't expire, this field
is set to (0x7fffffff,0xffffffff).
EffectiveName - This field contains the client's Windows 2000 UserName, stored in the Active
Directory in the SamAccountName property. This field is optional. If left blank the length, maxlength
and buffer are all zero.
FullName - this field contains the friendly name of the client, which is used only for display purpose
and not security purposes. This field is optional. If left blank the length, maxlength and buffer are all
zero.
LogonScript - This field contains the path to the client's logon script. This field is optional. If left blank
the length, maxlength and buffer are all zero.
ProfilePath - This field contains the path to the client's profile. This field is optional. If left blank the
length, maxlength and buffer are all zero.
HomeDirectory - This field contains the path to the client's home directory. It may be either a local
path name or a UNC path name. This field is optional. If left blank the length, maxlength and buffer
are all zero.
HomeDirectoryDrive - This field is only used if the client's home directory is a UNC path name. In that
case, the share on the remote file server is mapped to the local drive letter specified by this field.
This field is optional. If left blank the length, maxlength and buffer are all zero.
LogonCount - This field contains the count of how many times the client is currently logged on. This
statistic is not accurately maintained by Windows 2000 and should not be used.
BadPasswordCount - This field contains the number of logon or password change attempts with
bad passwords, since the last successful attempt.
* UserId - This field contains the relative Id for the client.
PrimaryGroupId - This field contains the relative ID for this client's primary group.
* GroupCount - This field contains the number of groups, within the client's domain, to which the
client is a member.
* GroupIds - This field contains an array of the relative Ids and attributes of the groups in the client's
domain of which the client is a member.
* UserFlags - This field contains information about which fields in this structure are valid. The two bits
that may be set are indicated below. Having these flags set indicates that the corresponding fields
in the KERB_VALIDATION_INFO structure are present and valid.
#define LOGON_EXTRA_SIDS 0x0020
#define LOGON_RESOURCE_GROUPS 0x0200
LogonServer - This field contains the NETBIOS name of the KDC which performed the AS ticket
request.

Windows 2000 Kerberos Authorization Data April 2000
© 2000 Microsoft Corporation. All rights reserved. Microsoft Confidential.
This Specification is provided pursuant to the terms and conditions of the Agreement for Microsoft Authorization Data Specification
v. 1.0 for Microsoft Windows 2000 Operating Systems (the "Agreement") for the sole purpose of allowing review of the
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Microsoft's website and agreed to the terms and conditions of the Agreement, you are not an authorized licensee of the Specification.
Page 5 of 12
LogonDomainName - This field contains the NETBIOS name of the client's domain.
* LogonDomainId - This field contains the SID of the client's domain. This field is used in conjunction
with the UserId, PrimaryGroupId,and GroupIds fields to create the user and group SIDs for the client.
UserAccountControl - This fields contains a bitfield of information about the client's account. Valid
values are:
#define USER_ACCOUNT_DISABLED (0x00000001)
#define USER_HOME_DIRECTORY_REQUIRED (0x00000002)
#define USER_PASSWORD_NOT_REQUIRED (0x00000004)
#define USER_TEMP_DUPLICATE_ACCOUNT (0x00000008)
#define USER_NORMAL_ACCOUNT (0x00000010)
#define USER_MNS_LOGON_ACCOUNT (0x00000020)
#define USER_INTERDOMAIN_TRUST_ACCOUNT (0x00000040)
#define USER_WORKSTATION_TRUST_ACCOUNT (0x00000080)
#define USER_SERVER_TRUST_ACCOUNT (0x00000100)
#define USER_DONT_EXPIRE_PASSWORD (0x00000200)
#define USER_ACCOUNT_AUTO_LOCKED (0x00000400)
#define USER_ENCRYPTED_TEXT_PASSWORD_ALLOWED (0x00000800)
#define USER_SMARTCARD_REQUIRED (0x00001000)
#define USER_TRUSTED_FOR_DELEGATION (0x00002000)
#define USER_NOT_DELEGATED (0x00004000)
#define USER_USE_DES_KEY_ONLY (0x00008000)
#define USER_DONT_REQUIRE_PREAUTH (0x00010000)
* SidCount - This field contains the number of SIDs present in the ExtraSids field. This field is only valid
if the LOGON_EXTRA_SIDS flag has been set in the UserFlags field.
* ExtraSids - This field contains a list of SIDs for groups to which the user is a member. This field is only
valid if the LOGON_EXTRA_SIDS flag has been set in the UserFlags field.
* ResouceGroupCount - This field contains the number of resource groups in the ResourceGroupIds
field. This field is only valid if the LOGON RESOURCE_GROUPS flag has been set in the UserFlags
field._
* ResourceGroupDomainSid - This field contains the SID of the resource domain. This field is used in
conjunction with the ResourceGroupIds field to create the group SIDs for the client.
* ResourceGroupIds - This field contains an array of the relative Ids and attributes of the groups in
the resource domain of which the resource is a member.
Fields marked with a '*' are used in the NT token.
When used in the KERB_VALIDATION_INFO, this is NDR encoded. The FILETIME type is defined as
follows:
typedef unsigned int DWORD;
typedef struct _FILETIME {
DWORD dwLowDateTime;
DWORD dwHighDateTime;
} FILETIME;

Windows 2000 Kerberos Authorization Data April 2000
© 2000 Microsoft Corporation. All rights reserved. Microsoft Confidential.
This Specification is provided pursuant to the terms and conditions of the Agreement for Microsoft Authorization Data Specification
v. 1.0 for Microsoft Windows 2000 Operating Systems (the "Agreement") for the sole purpose of allowing review of the
Specification for security analysis, as further specified in the Agreement. If you have not downloaded the Specification from
Microsoft's website and agreed to the terms and conditions of the Agreement, you are not an authorized licensee of the Specification.
Page 6 of 12
Times are encoded as the number of 100 nanosecond increments since January 1, 1601, in UTC
time.
When used in the KERB_VALIDATION_INFO, this is NDR encoded. The UNICODE_STRING structure is
defined as:
typedef struct _UNICODE_STRING
USHORT Length;
USHORT MaximumLength;
[size_is(MaximumLength / 2), length_is((Length) / 2) ] USHORT * Buffer;
} UNICODE_STRING;
The Length field contains the number of bytes in the string, not including the null terminator, and the
MaximumLength field contains the total number of bytes in the buffer containing the string.
The GROUP_MEMBERSHIP structure contains the relative ID of a group and the corresponding
attributes for the group.
typedef struct _GROUP_MEMBERSHIP {
ULONG RelativeId;
ULONG Attributes;
} *PGROUP_MEMBERSHIP;
The group attributes must be:
#define SE_GROUP_MANDATORY (0x00000001L)
#define SE_GROUP_ENABLED_BY_DEFAULT (0x00000002L)
#define SE_GROUP_ENABLED (0x00000004L)
The SID structure is defined as follows:
typedef struct _SID_IDENTIFIER_AUTHORITY {
UCHAR Value[6];
} SID_IDENTIFIER_AUTHORITY, *PSID_IDENTIFIER_AUTHORITY;
The constant value for the NT Authority is:
#define SECURITY_NT_AUTHORITY {0,0,0,0,0,5}
typedef struct _SID {
UCHAR Revision;
UCHAR SubAuthorityCount;

Windows 2000 Kerberos Authorization Data April 2000
© 2000 Microsoft Corporation. All rights reserved. Microsoft Confidential.
This Specification is provided pursuant to the terms and conditions of the Agreement for Microsoft Authorization Data Specification
v. 1.0 for Microsoft Windows 2000 Operating Systems (the "Agreement") for the sole purpose of allowing review of the
Specification for security analysis, as further specified in the Agreement. If you have not downloaded the Specification from
Microsoft's website and agreed to the terms and conditions of the Agreement, you are not an authorized licensee of the Specification.
Page 7 of 12
SID_IDENTIFIER_AUTHORITY IdentifierAuthority;
[size_is(SubAuthorityCount)] ULONG SubAuthority[*];
} SID, *PSID;
The SubAuthorityCount field contains the number of elements in the actual SubAuthority
conformant array. The maximum number of subauthorities allowed is 15.
The KERB_SID_AND_ATTRIBUTES structure contains entire group SIDs and their corresponding
attributes:
typedef struct _KERB_SID_AND_ATTRIBUTES {
PSID Sid;
ULONG Attributes;
} KERB_SID_AND_ATTRIBUTES, *PKERB_SID_AND_ATTRIBUTES;
The attributes are the same as the group attributes defined above.
Client Information
The client information is included in the PAC to allow a server to verify that the PAC in a ticket is
applicable to the client of the ticket, which prevents splicing of PACs between tickets. The
PAC_CLIENT_INFO structure is included in a PAC_INFO_BUFFER of type PAC_CLIENT_INFO_TYPE.
typedef struct _PAC_CLIENT_INFO {
FILETIME ClientId;
USHORT NameLength;
WCHAR Name[1];
} PAC_CLIENT_INFO, *PPAC_CLIENT_INFO;
The fields are defined as follows:
ClientId - This field contains a conversion of the AuthTime field of the ticket into a FILETIME structure.
NameLength - This field contains the length, in bytes, of the Name field.
Name - This field contains the client name from the ticket, converted to Unicode and encoded
using "/" to separate parts of the client principal name with an "@" separating the client principal
name from the realm name. The string is not null terminated.
Supplemental Credentials
The KDC may return supplemental credentials in the PAC as well. Supplemental credentials are
data associated with a security package that is private to that package. They can be used to
return an appropriate user key that is specific to that package for the purposes of authentication.
Supplemental creds are only used in conjunction with PKINIT[2]. Supplemental credentials are
always encrypted using the client key. The PAC_CREDENTIAL_DATA structure is NDR encoded and

Windows 2000 Kerberos Authorization Data April 2000
© 2000 Microsoft Corporation. All rights reserved. Microsoft Confidential.
This Specification is provided pursuant to the terms and conditions of the Agreement for Microsoft Authorization Data Specification
v. 1.0 for Microsoft Windows 2000 Operating Systems (the "Agreement") for the sole purpose of allowing review of the
Specification for security analysis, as further specified in the Agreement. If you have not downloaded the Specification from
Microsoft's website and agreed to the terms and conditions of the Agreement, you are not an authorized licensee of the Specification.
Page 8 of 12
then encrypted with the key used to encrypt the KDC's reply to the client. The
PAC_CREDENTIAL_INFO structure is included in PAC_INFO_BUFFER of type PAC_CREDENTIAL_TYPE.
Supplemental credentials for a single package are NDR encoded as follows:
typedef struct _SECPKG_SUPPLEMENTAL_CRED {
UNICODE_STRING PackageName;
ULONG CredentialSize;
[size_is(CredentialSize)]PUCHAR Credentials;
} SECPKG_SUPPLEMENTAL_CRED, *PSECPKG_SUPPLEMENTAL_CRED;
The fields in this structure are defined as follows:
PackageName - This field contains the name of the package for which credentials are presented.
CredentialSize - This field contains the length, in bytes, of the presented credentials.
Credentials - This field contains a pointer to the credential data.
The set of all supplemental credentials is NDR encoded in a PAC_CREDENTIAL_DATA structure:
typedef struct _PAC_CREDENTIAL_DATA {
ULONG CredentialCount;
[size_is(CredentialCount)] SECPKG_SUPPLEMENTAL_CRED Credentials[*];
} PAC_CREDENTIAL_DATA, *PPAC_CREDENTIAL_DATA;
The fields are defined as follows:
CredentialCount - This field contains the number of credential present in the Credentials array.
Credentials - This field contains an array of the presented supplemental credentials.
The PAC_CREDENTIAL_DATA structure is NDR encoded and then encrypted with the key used to
encrypt the KDC reply. The resulting buffer is returned in the following structure:
typedef struct _PAC_CREDENTIAL_INFO {
ULONG Version;
ULONG EncryptionType;
UCHAR Data[1];
} PAC_CREDENTIAL_INFO, *PPAC_CREDENTIAL_INFO;
The fields are defined as follows:
Version - This field contains the version field of the key used to encrypt the data, or zero if the field is
not present.

Windows 2000 Kerberos Authorization Data April 2000
© 2000 Microsoft Corporation. All rights reserved. Microsoft Confidential.
This Specification is provided pursuant to the terms and conditions of the Agreement for Microsoft Authorization Data Specification
v. 1.0 for Microsoft Windows 2000 Operating Systems (the "Agreement") for the sole purpose of allowing review of the
Specification for security analysis, as further specified in the Agreement. If you have not downloaded the Specification from
Microsoft's website and agreed to the terms and conditions of the Agreement, you are not an authorized licensee of the Specification.
Page 9 of 12
EncryptType - This field contains the encryption type used to encrypt the data. The encryption type
uses the same values as the defined encryptions types for Kerberos [1].
Data - This field contains an array of bytes containing the encrypted supplemental credential data.
Signatures
The PAC contains two digital signatures: one using the key of the server, and one using the key of
the KDC. The signatures are present for two reasons. First, the signature with the server's key is
present to prevent a client from generating their own PAC and sending it to the KDC as encrypted
authorization data to be included in tickets. Second, the signature with the KDC's key is present to
prevent an untrusted service from forging a ticket to itself with an invalid PAC. The two signatures
are sent in PAC_INFO_BUFFERs of type PAC_SERVER_CHECKSUM and PAC_KDC_CHECKSUM
respectively.
The signatures are contained in the following structure:
typedef struct _PAC_SIGNATURE_DATA {
ULONG SignatureType;
UCHAR Signature[1];
} PAC_SIGNATURE_DATA, *PPAC_SIGNATURE_DATA;
The fields are defined as follows:
SignatureType - This field contains the type of checksum used to create a signature. The checksum
must be a keyed checksum.
Signature - This field consists of an array of bytes containing the checksum data. The length of bytes
may be determined by the wrapping PAC_INFO_BUFFER structure.
For the server's checksum, the key used to generate the signature should be the same key used to
encrypt the ticket. Thus, if the enc_tkt_in_skey option is used, the session key from the server's TGT
should be used. The Key used to encrypt ticket-granting tickets is used to generate the KDC's
checksum.
The checksums are computed as follows:
1. The complete PAC is built, including space for both checksums
2. The data portion of both checksums is zeroed.
3. The entire PAC structure is checksummed with the server's key, and the result is stored in the
server's checksum structure.
4. The server's checksum is then checksummed with the KDC's key.
5. The checksum with the KDC key is stored in the KDC's checksum structure.

Windows 2000 Kerberos Authorization Data April 2000
© 2000 Microsoft Corporation. All rights reserved. Microsoft Confidential.
This Specification is provided pursuant to the terms and conditions of the Agreement for Microsoft Authorization Data Specification
v. 1.0 for Microsoft Windows 2000 Operating Systems (the "Agreement") for the sole purpose of allowing review of the
Specification for security analysis, as further specified in the Agreement. If you have not downloaded the Specification from
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Page 10 of 12
PAC Request Pre-Auth Data
Normally, the PAC is included in every pre-authenticated ticket received from an AS request.
However, a client may also explicitly request either to include or to not include the PAC. This is done
by sending the PAC-REQUEST preauth data.
KERB-PA-PAC-REQUEST ::= SEQUENCE {
include-pac[0] BOOLEAN -- if TRUE, and no PAC present,
-- include PAC.
---If FALSE, and PAC
-- present, remove PAC
}
The fields are defined as follows:
include-pac - This field indicates whether a PAC should be included or not. If the value is TRUE, a
PAC will be included independent of other preauth data. If the value is FALSE, then no PAC will be
included, even if other preauth data is present.
The preauth ID is:
#define KRB5_PADATA_PAC_REQUEST 128
References
1 Neuman, C., Kohl, J., Ts'o, T., "The Kerberos Network Authentication Service (V5)", draft-ietf-cat-kerberos-
revisions-05.txt, March 10, 2000
2 Tung, B., Hur, M., Medvinsky, A., Medvinsky, S., Wray, J., Trostle, J., " Public Key Cryptography for
Initial Authentication in Kerberos", draft-ietf-cat-kerberos-pk-init-11.txt, March 15, 2000

Windows 2000 Kerberos Authorization Data April 2000
© 2000 Microsoft Corporation. All rights reserved. Microsoft Confidential.
Page 11 of 12
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This Specification is provided to you pursuant to the terms and conditions of the Agreement for
Microsoft Authorization Data Specification v. 1.0 for Microsoft Windows 2000 Operating Systems (the
"Agreement") for the sole purpose of allowing you to review the Specification for security analysis,
as further specified in the Agreement. If you have not downloaded the Specification from
Microsoft's website and agreed to the terms and conditions of the Agreement, you are not an
authorized licensee of the Specification.
For your reference, the Agreement is reproduced below.
Agreement for Microsoft Authorization Data Specification v. 1.0
for Microsoft Windows 2000 Operating Systems
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Windows 2000 Kerberos Authorization Data April 2000
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Not a trade secret

[troyboy]

I am a law student and do not pretend to be qualified to give legal advice, but I think that the above posts which reveal the "secret" eliminate any basis for Microsoft to call this a trade secret. Once it is in the public, it is not a trade secret.

A similar case was presented in Religious Technology Center v. Netcom, 923 F. Supp. 1231 (N.D. Cal. 1995), where the judge held that RTC was unlikely to succeed in a trade secret suit against someone who had obtained the documents on USENET. The judge said that "although a work posted to an Internet newsgroup remains accessible to the public for only a limited time, once that trade secret has been released into the public domain there is no retrieving it."

Now, the poster may be liable for breaching the contract, but it is no longer a trade secret...

Better than a patent

[Thagg]

I don't blame you if you missed it during the DeCSS imbroglio, but this is so clear that it is unmistakable.

A way to get *permanent* protection over an idea or an implementation is to cause the secret to be leaked illegally.

Then, you sue everybody who implements the idea, at any time in the future, saying that they were inspired, or at least tainted, by the illegal release of the information. Trade secret laws do not allow the use of a secret if 'sufficient protections are taken'.

Previously, I had thought that a company would need a shill to do the publication of the secret; which is of course dangerous if the shill squeals. Microsoft has shown their ability to innovate here; publishing it as a secret sure to be 'improperly' released is a much better scheme.

thad

Re:Defeating Trade Secrets 101:

[Sloppy]

I did NOT agree (nor did I even SEE) the license, and I now have access to the .pdf file. I will give copies of the .pdf file to anyone who asks, its public domain as far as I'm concerned.

Surely you jest. If failing to read a license causes me not to be bound by it, then maybe I'll just download the Linux kernel code, ignore the license, and call it public domain. Then, if it's public domain (and no longer GPLed), I can compile it and distribute binaries without source.

The license exists, and not reading it has no effect on whether you are licensed or not.

The power of the license, on the other hand, is quite debatable.

---

Re:Does this hamper legitimate reverse-engineering

[NMerriam]

Does this hamper legitimate reverse-engineering of the product?

No more than IBM hampered Compaq from reverse-engineering the original IBM-PC BIOS back in '83.

IBM actively published the BIOS specifications for exactly the reason you state -- it made it improbably that anyone technically capable of reverse-engineering it had not been exposed to the "trade secret". They thought it would make bulletproof legal protection.

Compaq had to search wide and far to find a team of engineeres who could swear they had never seen or heard anything about the BIOS "trade secrets". They locked them in a room with a black box version of the IBM-PC, and a second team "outside the room" (since they had been exposed to the trade secrets) would tell them whether they were hot or cold. They reverse-engineered it in one of the most important feats of the computer age.

And they kept detailed logs & journals of every step along the way so that they could prove beyond a doubt that they had succeeded in reverse-engineering the BIOS without seeing the published "secrets".

This may be, alas, further proof of Microsoft's fall -- they truly are becoming like IBM was back then, using tricks and traps to protect themselves rather than building a better mousetrap.

What's sad is that MS, Compaq, et al -- who would not exist without that single feat of engineering -- are more than happy to support laws that would prevent it from happening again (DMCA, etc).

Defeating Trade Secrets 101:

[iCEBaLM]

1. Download the evaluation copy of winzip if you don't already have it.

2. Download the dumb exe thing.

3. Open Winzip, and then open the exe WITH WINZIP.

4. Extract the PDF without agreeing to the license.

This is what I have done, I did NOT agree (nor did I even SEE) the license, and I now have access to the .pdf file. I will give copies of the .pdf file to anyone who asks, its public domain as far as I'm concerned.

-- iCEBaLM

Re:Defeating Trade Secrets 101:

[Ephro]

Trade secrets MUST have the following conditions met to be held up in court as a trade secret:
1) have novelty
2) represent an economic investment to the claimant
3) have involved some effort in development
4) the company must show that it made some effort to keep the information a secret

In addion to this, although it is not legal to use redistribute trade secrets, the general knowledge that is learned through things that are held under trade secrecy CAN be used in the future. Another point to remember is that if something is held under trade secret copyright and patent laws DO NOT apply. It is debatable in this case whether the company tried to keep it a secret (documents downloaded by hackers have fallen under trade secret laws, but because they were not secured enough so a hacker couldn't get access the hacker has been determined to not be liable for any damages.) Also any country where there are not trade secrecy laws could download this and redistribute it. Once a trade secret is not a secret it falls into public domain.

Some information gathered from Computer Ethics, Deborah G. Johnson, 1994.

Re:Did Micro$oft have to do this.

[tytso]

The legal problem with what they're doing is that they're deliberately making their software non-interoperable with published standards. This seems to indicate that they're trying to use their monopoly position to exclude competition, which is illegal.

Yes, that's it in a nutshell. The game here is that they're trying to use their monopoly in the desktop space to dislodge Unix in the server market. One of the ways they do this is by making the Windows 2000 PDC "look" like it embraces open standards, so that the I/T departments in Fortune 500 departments (which up until now have very often used Unix/Linux systems in their back offices) think that using Windows servers, and the Windows 2000 PDC in particular, is mostly harmless.

But the Windows 2000 clients have been architected so that you only get a bunch of cool features if you use their propietary protocol extensions. So it's clear that Microsoft is trying to create a monopoly situation with the Windows 2000 PDC, and once they control enough of the servers, they'll have an even tighter lock on the client market, and vice versa.

In my opinion, the DOJ really should have proposed splitting Microsoft's OS operations into a Client OS company and a Server OS company, in addition to splitting away the Office operations. Unfortunately, given that they've already submitted their proposal, it may be too late to fix things. Simply splitting the Office group away isn't going to stop Microsoft from playing dirty tricks in the client/server OS space, just as they've done here.

Re:Loophole?

[ka9dgx]

http://warot.com/freedom/kerbspec.pdf
What happens now?
--Mike--

Re:Loophole?

[RickyRay]

Seems to me like we could eliminate the entire issue by convincing the official maintainers of Kerberos to give an official use for the byte M$ took over (in the next release). Then the only way M$ would be able to remain compliant with the spec is to remove their proprietary addon.

Is "Kerberos" trademarked?

[Greyfox]

If they're not conformant with a open and trademarked standard, they should not be allowed to say they are. Actually, even if it's not trademarked, I wonder if you could sue them for fraudulently misleading the customer into believing the OS will work seamlessly in their existing Kerberos network.

An easy way...

[GNUs-Not-Good]

to keep it secret. Put the pdf file on an IIS server. No one will find it there because there are no IIS exploits.