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MacOS keychain database file format.asciidoc

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MacOS keychain database file format

Summary

The MacOS keychain database file format is used by MacOS to store keys. This specification is based on the source code and documentation.

This document is intended as a working document for the MacOS keychain database file format specification.

Document information

Author(s):

Joachim Metz <joachim.metz@gmail.com>

Abstract:

MacOS keychain database file format

Classification:

Public

Keywords:

keychain

License

Copyright (C) 2018-2021, Joachim Metz <joachim.metz@gmail.com>.
Permission is granted to copy, distribute and/or modify this document under the
terms of the GNU Free Documentation License, Version 1.3 or any later version
published by the Free Software Foundation; with no Invariant Sections, no
Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included
in the section entitled "GNU Free Documentation License".

Revision history

Version Author Date Comments

0.0.1

J.B. Metz

June 2018

Initial version.

0.0.2

J.B. Metz

August 2018

Additional information.

0.0.3

J. Aguilar

July 2019

Additional information about X509 certificate record (CSSM_DL_DB_RECORD_X509_CERTIFICATE).

0.0.4

J.B. Metz

May 2021

Changes to formatting.

1. Overview

  • file header

  • tables array

  • one or more tables

Characteristics Description

Byte order

big-endian

Date and time values

Character strings

2. File header

The file header is 20 bytes of size and consists of:

Offset Size Value Description

0

4

"kych"

Signature

4

2

1

Major format version

6

2

0

Minor format version

8

4

16

Unknown (Header data size or offset to unknown)

12

4

Tables array offset

16

4

Unknown
Seen: 0

3. Tables array

The tables array is variable of size and consists of:

Offset Size Value Description

0

4

Data size
Contains the size of the tables array data including the 4 bytes of the data size itself

4

4

Number of tables

8

4 x number of tables

Table offsets
The offset is relative to the start of the tables array

…​

…​

Tables array data

4. Table

A table consist of:

  • table header

  • zero or more records

  • Unknown (trailing data)

Table trailing data:
0x00000000  00 00 00 08 00 00 00 00                           ........

4.1. Table header

The table header is variable of size and consists of:

Offset Size Value Description

0

4

Data size
Contains the size of the table data including the 4 bytes of the data size itself

4

4

Record type
See section: Record types

8

4

Number of records

12

4

Records array offset
The offset is relative to the start of the table header

16

4

Unknown (Index offset?)

20

4

Unknown
Seen: 0x00, 0x1d

24

4

Number of record offsets

28

4 x number of records

Record offsets
The offset is relative to the start of the table header, or 0 if not set

4.2. Record types

Value Identifier Description

0x00000000

CSSM_DL_DB_SCHEMA_INFO

Record identifiers and table names

0x00000001

CSSM_DL_DB_SCHEMA_INDEXES

0x00000002

CSSM_DL_DB_SCHEMA_ATTRIBUTES

0x00000003

CSSM_DL_DB_SCHEMA_PARSING_MODULE

0x0000000a

CSSM_DL_DB_RECORD_ANY

0x0000000b

CSSM_DL_DB_RECORD_CERT

0x0000000c

CSSM_DL_DB_RECORD_CRL

0x0000000d

CSSM_DL_DB_RECORD_POLICY

0x0000000e

CSSM_DL_DB_RECORD_GENERIC

0x0000000f

CSSM_DL_DB_RECORD_PUBLIC_KEY

0x00000010

CSSM_DL_DB_RECORD_PRIVATE_KEY

0x00000011

CSSM_DL_DB_RECORD_SYMMETRIC_KEY

0x00000012

CSSM_DL_DB_RECORD_ALL_KEYS

0x80000000

CSSM_DL_DB_RECORD_GENERIC_PASSWORD

Generic passwords

0x80000001

CSSM_DL_DB_RECORD_INTERNET_PASSWORD

Internet passwords

0x80000002

CSSM_DL_DB_RECORD_APPLESHARE_PASSWORD

0x80000003

CSSM_DL_DB_RECORD_USER_TRUST

0x80000004

CSSM_DL_DB_RECORD_X509_CRL

0x80000005

CSSM_DL_DB_RECORD_UNLOCK_REFERRAL

0x80000006

CSSM_DL_DB_RECORD_EXTENDED_ATTRIBUTE

0x80001000

CSSM_DL_DB_RECORD_X509_CERTIFICATE

0x80008000

CSSM_DL_DB_RECORD_METADATA

Note
The MSB (0x80000000) of the value indicates application specific tables.

5. Record

A record consist of:

  • record header

  • attribute value offsets

  • Unknown (Opional key data?)

  • attribute values data

  • Unknown (padding)

5.1. Record header

The record header is 24 bytes of size and consists of:

Offset Size Value Description

0

4

Data size
Contains the size of the record data including the 4 bytes of the data size itself

4

4

Unknown (record index)

8

4

Unknown

12

4

Unknown

16

4

Unknown (key data size)

20

4

Unknown

5.2. Attribute value offsets

The attribute value offset are variable of size and consists of:

Offset Size Value Description

0

4 x number of attributes

Attribute value offset
The offset is relative to the start of the record header - 1, or 0 if value is empty (NULL)

The number of attributes is dependent on the record type.

5.3. CSSM_DL_DB_SCHEMA_INFO attribute values

The CSSM_DL_DB_SCHEMA_INFO (or CSSM_DL_DB_SCHEMA_RELATIONS) attribute values data consists of:

Attribute number Attribute name Data type Attribute description

0

RelationID

Integer 32-bit unsigned

Record type (or relation identifier)
See section: Record types

1

RelationName

String with size

Table name (or relation name)

5.4. CSSM_DL_DB_SCHEMA_INDEXES attribute values

The CSSM_DL_DB_SCHEMA_INDEXES attribute values data consists of:

Attribute number Attribute name Data type Attribute description

0

RelationID

Integer 32-bit unsigned

Record type (or relation identifier)
See section: Record types

1

IndexID

Integer 32-bit unsigned

Index identifier

2

AttributeID

Integer 32-bit unsigned

Attribute identifier

3

IndexType

Integer 32-bit unsigned

Index type

4

IndexedDataLocation

Integer 32-bit unsigned

Location of the source data used to create the index

5.5. CSSM_DL_DB_SCHEMA_ATTRIBUTES attribute values

The CSSM_DL_DB_SCHEMA_ATTRIBUTES attribute values data consists of:

Attribute number Attribute name Data type Attribute description

0

RelationID

Integer 32-bit unsigned

Record type (or relation identifier)
See section: Record types

1

AttributeID

Integer 32-bit unsigned

Attribute identifier

2

AttributeNameFormat

Integer 32-bit unsigned

Data type of the attribute name
See section: Attribute data types

3

AttributeName

Attribute name

4

AttributeNameID

Binary data

Identifier of the attribute name
Contains an OID

5

AttributeFormat

Integer 32-bit unsigned

Data type of the attribute value
See section: Attribute data types

Note
The data type of AttributeName is depedent on AttributeNameFormat

5.6. CSSM_DL_DB_SCHEMA_PARSING_MODULE attribute values

The CSSM_DL_DB_SCHEMA_PARSING_MODULE attribute values data consists of:

Attribute number Attribute name Data type Attribute description

0

RelationID

Integer 32-bit unsigned

Record type (or relation identifier)
See section: Record types

1

AttributeID

Integer 32-bit unsigned

Attribute identifier

2

ModuleID

Binary data

Module identifier
Contains a GUID/UUID

3

AddinVersion

String with size

Module version

4

SSID

Integer 32-bit unsigned

Subservice module identifier

5

SubserviceType

Integer 32-bit unsigned

Subservice module type

5.7. CSSM_DL_DB_RECORD_CERT attribute values

Attribute Name	Attribute Type	Attribute Description
CertType	CSSM_CERT_TYPE	One of the values defined for CSSM_CERT_TYPE.
CertEncoding	CSSM_CERT_ENCODING	One of the values defined for CSSM_CERT_ENCODING.
PrintName	CSSM_Data
(max length 16 characters)	The PrintName attribute required in all DL-stored records.
Alias	CSSM_Data
(max length 8 bytes)	The Alias attribute required in all DL-stored records.

5.8. CSSM_DL_DB_RECORD_CERT attribute values

Attribute Name	Attribute Type	Attribute Description
CrlType	CSSM_CRL_TYPE	One of the values defined for CSSM_CRL_TYPE.
CrlEncoding	CSSM_CRL_ENCODING	One of the values defined for CSSM_CRL_ENCODING.
PrintName	CSSM_Data
(max length 16 characters)	The PrintName attribute required in all DL-stored records.
Alias	CSSM_Data
(max length 8 bytes)	The Alias attribute required in all DL-stored records.

5.9. CSSM_DL_DB_RECORD_POLICY attribute values

Attribute Name	Attribute Type	Attribute Description
PolicyName	CSSM_OID	One of the values defined by the policy domain.
PrintName	CSSM_Data
(max length 16 characters)	The PrintName attribute required in all DL-stored records.
Alias	CSSM_Data
(max length 8 bytes)	The Alias attribute required in all DL-stored records.

5.10. CSSM_DL_DB_RECORD_GENERIC attribute values

Attribute Name	Attribute Type	Attribute Description
PrintName	CSSM_Data
(max length 16 characters)	The PrintName attribute required in all DL-stored records.
Alias	CSSM_Data
(max length 8 bytes)	The Alias attribute required in all DL-stored records.

5.11. CSSM_DL_DB_RECORD_PUBLIC_KEY attribute values

The CSSM_DL_DB_RECORD_PUBLIC_KEY attribute values data consists of:

Attribute number Attribute name Data type Attribute description

KeyClass

PrintName

Alias

Permanent

Private

Modifiable

Label

ApplicationTag

KeyCreator

KeyType

KeySizeInBits

EffectiveKeySize

StartDate

EndDate

Sensitive

AlwaysSensitive

Extractable

NeverExtractable

Encrypt

Decrypt

Derive

Sign

Verify

SignRecover

VerifyRecover

Wrap

Unwrap

5.12. CSSM_DL_DB_RECORD_PRIVATE_KEY attribute values

The CSSM_DL_DB_RECORD_PRIVATE_KEY attribute values data consists of:

Attribute number Attribute name Data type Attribute description

KeyClass

PrintName

Alias

Permanent

Private

Modifiable

Label

ApplicationTag

KeyCreator

KeyType

KeySizeInBits

EffectiveKeySize

StartDate

EndDate

Sensitive

AlwaysSensitive

Extractable

NeverExtractable

Encrypt

Decrypt

Derive

Sign

Verify

SignRecover

VerifyRecover

Wrap

Unwrap

5.13. CSSM_DL_DB_RECORD_SYMMETRIC_KEY attribute values

The CSSM_DL_DB_RECORD_SYMMETRIC_KEY attribute values data consists of:

Attribute number Attribute name Data type Attribute description

KeyClass

PrintName

Alias

Permanent

Private

Modifiable

Label

ApplicationTag

KeyCreator

KeyType

KeySizeInBits

EffectiveKeySize

StartDate

EndDate

Sensitive

AlwaysSensitive

Extractable

NeverExtractable

Encrypt

Decrypt

Derive

Sign

Verify

SignRecover

VerifyRecover

Wrap

Unwrap

5.14. CSSM_DL_DB_RECORD_GENERIC_PASSWORD attribute values

The CSSM_DL_DB_RECORD_GENERIC_PASSWORD attribute values data consists of:

Attribute number Attribute name Data type Attribute description

0

cdat

Date and time

1

mdat

Date and time

2

desc

Binary data

3

icmt

Binary data

4

crtr

Integer 32-bit unsigned

Item creator tag (kSecCreatorItemAttr)

5

type

Integer 32-bit unsigned

6

scrp

Integer 32-bit unsigned

7

PrintName

Binary data

8

Alias

Binary data

9

invi

Integer 32-bit unsigned

10

nega

Integer 32-bit unsigned

11

cusi

Integer 32-bit unsigned

12

prot

Binary data

13

acct

Binary data

14

svce

Binary data

15

gena

Binary data

5.15. CSSM_DL_DB_RECORD_INTERNET_PASSWORD attribute values

The CSSM_DL_DB_RECORD_INTERNET_PASSWORD attribute values data consists of:

Attribute number Attribute name Data type Attribute description

0

cdat

Date and time

1

mdat

Date and time

2

desc

Binary data

3

icmt

Binary data

4

crtr

Integer 32-bit unsigned

Item creator tag (kSecCreatorItemAttr)

5

type

Integer 32-bit unsigned

6

scrp

Integer 32-bit unsigned

7

PrintName

Binary data

8

Alias

Binary data

9

invi

Integer 32-bit unsigned

10

nega

Integer 32-bit unsigned

11

cusi

Integer 32-bit unsigned

12

prot

Binary data

13

acct

Binary data

14

sdmn

Binary data

15

srvr

Binary data

16

ptcl

Integer 32-bit unsigned

17

atyp

Binary data

18

port

Integer 32-bit unsigned

19

path

Binary data

5.16. CSSM_DL_DB_RECORD_APPLESHARE_PASSWORD attribute values

The CSSM_DL_DB_RECORD_APPLESHARE_PASSWORD attribute values data consists of:

Attribute number Attribute name Data type Attribute description

0

cdat

Date and time

1

mdat

Date and time

2

desc

Binary data

3

icmt

Binary data

4

crtr

Integer 32-bit unsigned

Item creator tag (kSecCreatorItemAttr)

5

type

Integer 32-bit unsigned

6

scrp

Integer 32-bit unsigned

7

PrintName

Binary data

8

Alias

Binary data

9

invi

Integer 32-bit unsigned

10

nega

Integer 32-bit unsigned

11

cusi

Integer 32-bit unsigned

12

prot

Binary data

13

acct

Binary data

14

vlme

Binary data

15

srvr

Binary data

16

ptcl

Integer 32-bit unsigned

17

addr

Binary data

18

ssig

Binary data

5.17. CSSM_DL_DB_RECORD_USER_TRUST attribute values

5.18. CSSM_DL_DB_RECORD_X509_CRL attribute values

5.19. CSSM_DL_DB_RECORD_UNLOCK_REFERRAL attribute values

5.20. CSSM_DL_DB_RECORD_EXTENDED_ATTRIBUTE attribute values

5.21. CSSM_DL_DB_RECORD_X509_CERTIFICATE attribute values

Attribute number Attribute name Data type Attribute description

0

CertType

Integer 32-bit unsigned

1

CertEncoding

Integer 32-bit unsigned

2

PrintName

Binary data

3

Alias

Binary data

4

Subject

Binary data

5

Issuer

Binary data

6

SerialNumber

Binary data

7

SubjectKeyIdentifier

Binary data

8

PublicKeyHash

Binary data

5.22. CSSM_DL_DB_RECORD_METADATA attribute values

6. Attribute data types

The attribute data types (or formats):

Value Identifier Description

0

CSSM_DB_ATTRIBUTE_FORMAT_STRING

+ See section: String data type

1

CSSM_DB_ATTRIBUTE_FORMAT_SINT32

Integer 32-bit signed

2

CSSM_DB_ATTRIBUTE_FORMAT_UINT32

Integer 32-bit unsigned

3

CSSM_DB_ATTRIBUTE_FORMAT_BIG_NUM

4

CSSM_DB_ATTRIBUTE_FORMAT_REAL

Floating-point 64-bit

5

CSSM_DB_ATTRIBUTE_FORMAT_TIME_DATE

Date and time
See section: Date time data type

6

CSSM_DB_ATTRIBUTE_FORMAT_BLOB

Binary data

7

CSSM_DB_ATTRIBUTE_FORMAT_MULTI_UINT32

8

CSSM_DB_ATTRIBUTE_FORMAT_COMPLEX

6.1. Binary data type

The binary data type is variable of size and consists of:

Offset Size Value Description

0

4

Binary data size

4

…​

Binary data

6.2. Date time data type

The date time data type is at 16 bytes of size and consists of:

Offset Size Value Description

0

4

Date and time string
The string is formatted as "YYYYMMDDhhmmssZ", with an end-of-string character

6.3. String data type

The string data type is variable of size and consists of:

Offset Size Value Description

0

4

String size

4

…​

String
The end-of-string character is optional
The encoding is platform specific

6.4. Notes

BIG_NUM

This is a sign-magnitude little-endian integer of arbitrary size. The first bit represents the sign of the number (0 == positive, 1 == negative, zero is non-deterministic), all other bits represent the magnitude. Padding zeros are allowed.

MULTI_UINT32

An array of uint32s. The length of this structure must be a multiple of four. Greater than and less than operations are performed by comparing the binary value of each uint32.

COMPLEX

A non-standard or complex structure. The type is further defined by the attribute's name. (for example, if AttributeName = APP_DOMAIN_STRUCTURED_NAME, then the implied type is a application-defined structure containing a name). Use of this type is not recommended.

7. Notes

Look into file name changes in MacOS 10.12 from .keychain to .keychain-db if that also imposed format changes.

Module specific attribute identifiers:

    'cdat': 'kSecCreationDateItemAttr',
    'mdat': 'kSecModDateItemAttr',
    'desc': 'kSecDescriptionItemAttr',
    'icmt': 'kSecCommentItemAttr',
    'crtr': 'kSecCreatorItemAttr',
    'type': 'kSecTypeItemAttr',
    'scrp': 'kSecScriptCodeItemAttr',
    'labl': 'kSecLabelItemAttr',
    'invi': 'kSecInvisibleItemAttr',
    'nega': 'kSecNegativeItemAttr',
    'cusi': 'kSecCustomIconItemAttr',
    'acct': 'kSecAccountItemAttr',
    'svce': 'kSecServiceItemAttr',
    'gena': 'kSecGenericItemAttr',
    'sdmn': 'kSecSecurityDomainItemAttr',
    'srvr': 'kSecServerItemAttr',
    'atyp': 'kSecAuthenticationTypeItemAttr',
    'port': 'kSecPortItemAttr',
    'path': 'kSecPathItemAttr',
    'vlme': 'kSecVolumeItemAttr',
    'addr': 'kSecAddressItemAttr',
    'ssig': 'kSecSignatureItemAttr',
    'ptcl': 'kSecProtocolItemAttr',
    'ctyp': 'kSecCertificateType',
    'cenc': 'kSecCertificateEncoding',
    'crtp': 'kSecCrlType',
    'crnc': 'kSecCrlEncoding',
    'alis': 'kSecAlias',
    'inet': 'kSecInternetPasswordItemClass',
    'genp': 'kSecGenericPasswordItemClass',
    'ashp': 'kSecAppleSharePasswordItemClass',
    0x80001000: 'kSecCertificateItemClass'

Appendix A: References

[OPENGROUP]

Title: Common Security: CDSA and CSSM

Version:

2

URL:

http://pubs.opengroup.org/onlinepubs/009608599/

Appendix B: GNU Free Documentation License

Version 1.3, 3 November 2008 Copyright © 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc. http://fsf.org/

Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.

0. PREAMBLE

The purpose of this License is to make a manual, textbook, or other functional and useful document "free" in the sense of freedom: to assure everyone the effective freedom to copy and redistribute it, with or without modifying it, either commercially or noncommercially. Secondarily, this License preserves for the author and publisher a way to get credit for their work, while not being considered responsible for modifications made by others.

This License is a kind of "copyleft", which means that derivative works of the document must themselves be free in the same sense. It complements the GNU General Public License, which is a copyleft license designed for free software.

We have designed this License in order to use it for manuals for free software, because free software needs free documentation: a free program should come with manuals providing the same freedoms that the software does. But this License is not limited to software manuals; it can be used for any textual work, regardless of subject matter or whether it is published as a printed book. We recommend this License principally for works whose purpose is instruction or reference.

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This License applies to any manual or other work, in any medium, that contains a notice placed by the copyright holder saying it can be distributed under the terms of this License. Such a notice grants a world-wide, royalty-free license, unlimited in duration, to use that work under the conditions stated herein. The "Document", below, refers to any such manual or work. Any member of the public is a licensee, and is addressed as "you". You accept the license if you copy, modify or distribute the work in a way requiring permission under copyright law.

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2. VERBATIM COPYING

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  8. Include an unaltered copy of this License.

  9. Preserve the section Entitled "History", Preserve its Title, and add to it an item stating at least the title, year, new authors, and publisher of the Modified Version as given on the Title Page. If there is no section Entitled "History" in the Document, create one stating the title, year, authors, and publisher of the Document as given on its Title Page, then add an item describing the Modified Version as stated in the previous sentence.

  10. Preserve the network location, if any, given in the Document for public access to a Transparent copy of the Document, and likewise the network locations given in the Document for previous versions it was based on. These may be placed in the "History" section. You may omit a network location for a work that was published at least four years before the Document itself, or if the original publisher of the version it refers to gives permission.

  11. For any section Entitled "Acknowledgements" or "Dedications", Preserve the Title of the section, and preserve in the section all the substance and tone of each of the contributor acknowledgements and/or dedications given therein.

  12. Preserve all the Invariant Sections of the Document, unaltered in their text and in their titles. Section numbers or the equivalent are not considered part of the section titles.

  13. Delete any section Entitled "Endorsements". Such a section may not be included in the Modified Version.

  14. Do not retitle any existing section to be Entitled "Endorsements" or to conflict in title with any Invariant Section.

  15. Preserve any Warranty Disclaimers.

If the Modified Version includes new front-matter sections or appendices that qualify as Secondary Sections and contain no material copied from the Document, you may at your option designate some or all of these sections as invariant. To do this, add their titles to the list of Invariant Sections in the Modified Version’s license notice. These titles must be distinct from any other section titles.

You may add a section Entitled "Endorsements", provided it contains nothing but endorsements of your Modified Version by various parties—for example, statements of peer review or that the text has been approved by an organization as the authoritative definition of a standard.

You may add a passage of up to five words as a Front-Cover Text, and a passage of up to 25 words as a Back-Cover Text, to the end of the list of Cover Texts in the Modified Version. Only one passage of Front-Cover Text and one of Back-Cover Text may be added by (or through arrangements made by) any one entity. If the Document already includes a cover text for the same cover, previously added by you or by arrangement made by the same entity you are acting on behalf of, you may not add another; but you may replace the old one, on explicit permission from the previous publisher that added the old one.

The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version.

5. COMBINING DOCUMENTS

You may combine the Document with other documents released under this License, under the terms defined in section 4 above for modified versions, provided that you include in the combination all of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice, and that you preserve all their Warranty Disclaimers.

The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work.

In the combination, you must combine any sections Entitled "History" in the various original documents, forming one section Entitled "History"; likewise combine any sections Entitled "Acknowledgements", and any sections Entitled "Dedications". You must delete all sections Entitled "Endorsements".

6. COLLECTIONS OF DOCUMENTS

You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.

You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document.

7. AGGREGATION WITH INDEPENDENT WORKS

A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, is called an "aggregate" if the copyright resulting from the compilation is not used to limit the legal rights of the compilation’s users beyond what the individual works permit. When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document.

If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document’s Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate.

8. TRANSLATION

Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail.

If a section in the Document is Entitled "Acknowledgements", "Dedications", or "History", the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.

9. TERMINATION

You may not copy, modify, sublicense, or distribute the Document except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense, or distribute it is void, and will automatically terminate your rights under this License.

However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.

Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.

Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, receipt of a copy of some or all of the same material does not give you any rights to use it.

10. FUTURE REVISIONS OF THIS LICENSE

The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See http://www.gnu.org/copyleft/.

Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License "or any later version" applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation. If the Document specifies that a proxy can decide which future versions of this License can be used, that proxy’s public statement of acceptance of a version permanently authorizes you to choose that version for the Document.

11. RELICENSING

"Massive Multiauthor Collaboration Site" (or "MMC Site") means any World Wide Web server that publishes copyrightable works and also provides prominent facilities for anybody to edit those works. A public wiki that anybody can edit is an example of such a server. A "Massive Multiauthor Collaboration" (or "MMC") contained in the site means any set of copyrightable works thus published on the MMC site.

"CC-BY-SA" means the Creative Commons Attribution-Share Alike 3.0 license published by Creative Commons Corporation, a not-for-profit corporation with a principal place of business in San Francisco, California, as well as future copyleft versions of that license published by that same organization.

"Incorporate" means to publish or republish a Document, in whole or in part, as part of another Document.

An MMC is "eligible for relicensing" if it is licensed under this License, and if all works that were first published under this License somewhere other than this MMC, and subsequently incorporated in whole or in part into the MMC, (1) had no cover texts or invariant sections, and (2) were thus incorporated prior to November 1, 2008.

The operator of an MMC Site may republish an MMC contained in the site under CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing.