draft-ietf-kitten-sasl-oauth-16.txt | draft-ietf-kitten-sasl-oauth-17.txt | |||
---|---|---|---|---|
KITTEN W. Mills | KITTEN W. Mills | |||
Internet-Draft Microsoft | Internet-Draft Microsoft | |||
Intended status: Standards Track T. Showalter | Intended status: Standards Track T. Showalter | |||
Expires: March 20, 2015 | Expires: May 16, 2015 | |||
H. Tschofenig | H. Tschofenig | |||
ARM Ltd. | ARM Ltd. | |||
September 16, 2014 | November 12, 2014 | |||
A set of SASL Mechanisms for OAuth | A set of SASL Mechanisms for OAuth | |||
draft-ietf-kitten-sasl-oauth-16.txt | draft-ietf-kitten-sasl-oauth-17.txt | |||
Abstract | Abstract | |||
OAuth enables a third-party application to obtain limited access to a | OAuth enables a third-party application to obtain limited access to a | |||
protected resource, either on behalf of a resource owner by | protected resource, either on behalf of a resource owner by | |||
orchestrating an approval interaction, or by allowing the third-party | orchestrating an approval interaction, or by allowing the third-party | |||
application to obtain access on its own behalf. | application to obtain access on its own behalf. | |||
This document defines how an application client uses credentials | This document defines how an application client uses credentials | |||
obtained via OAuth over the Simple Authentication and Security Layer | obtained via OAuth over the Simple Authentication and Security Layer | |||
skipping to change at page 2, line 4 | skipping to change at page 2, line 4 | |||
Internet-Drafts are working documents of the Internet Engineering | Internet-Drafts are working documents of the Internet Engineering | |||
Task Force (IETF). Note that other groups may also distribute | Task Force (IETF). Note that other groups may also distribute | |||
working documents as Internet-Drafts. The list of current Internet- | working documents as Internet-Drafts. The list of current Internet- | |||
Drafts is at http://datatracker.ietf.org/drafts/current/. | Drafts is at http://datatracker.ietf.org/drafts/current/. | |||
Internet-Drafts are draft documents valid for a maximum of six months | Internet-Drafts are draft documents valid for a maximum of six months | |||
and may be updated, replaced, or obsoleted by other documents at any | and may be updated, replaced, or obsoleted by other documents at any | |||
time. It is inappropriate to use Internet-Drafts as reference | time. It is inappropriate to use Internet-Drafts as reference | |||
material or to cite them other than as "work in progress." | material or to cite them other than as "work in progress." | |||
This Internet-Draft will expire on March 20, 2015. | This Internet-Draft will expire on May 16, 2015. | |||
Copyright Notice | Copyright Notice | |||
Copyright (c) 2014 IETF Trust and the persons identified as the | Copyright (c) 2014 IETF Trust and the persons identified as the | |||
document authors. All rights reserved. | document authors. All rights reserved. | |||
This document is subject to BCP 78 and the IETF Trust's Legal | This document is subject to BCP 78 and the IETF Trust's Legal | |||
Provisions Relating to IETF Documents | Provisions Relating to IETF Documents | |||
(http://trustee.ietf.org/license-info) in effect on the date of | (http://trustee.ietf.org/license-info) in effect on the date of | |||
publication of this document. Please review these documents | publication of this document. Please review these documents | |||
skipping to change at page 2, line 31 | skipping to change at page 2, line 31 | |||
Table of Contents | Table of Contents | |||
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 | 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 | |||
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5 | 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5 | |||
3. OAuth SASL Mechanism Specifications . . . . . . . . . . . . . 6 | 3. OAuth SASL Mechanism Specifications . . . . . . . . . . . . . 6 | |||
3.1. Initial Client Response . . . . . . . . . . . . . . . . . 7 | 3.1. Initial Client Response . . . . . . . . . . . . . . . . . 7 | |||
3.1.1. Reserved Key/Values . . . . . . . . . . . . . . . . . 8 | 3.1.1. Reserved Key/Values . . . . . . . . . . . . . . . . . 8 | |||
3.2. Server's Response . . . . . . . . . . . . . . . . . . . . 8 | 3.2. Server's Response . . . . . . . . . . . . . . . . . . . . 8 | |||
3.2.1. OAuth Identifiers in the SASL Context . . . . . . . . 8 | 3.2.1. OAuth Identifiers in the SASL Context . . . . . . . . 8 | |||
3.2.2. Server Response to Failed Authentication . . . . . . 9 | 3.2.2. Server Response to Failed Authentication . . . . . . 9 | |||
3.2.3. Completing an Error Message Sequence . . . . . . . . 9 | 3.2.3. Completing an Error Message Sequence . . . . . . . . 10 | |||
3.3. OAuth Access Token Types using Keyed Message Digests . . 10 | 3.3. OAuth Access Token Types using Keyed Message Digests . . 10 | |||
4. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 11 | 4. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 11 | |||
4.1. Successful Bearer Token Exchange . . . . . . . . . . . . 11 | 4.1. Successful Bearer Token Exchange . . . . . . . . . . . . 11 | |||
4.2. Successful OAuth 1.0a Token Exchange . . . . . . . . . . 12 | 4.2. Successful OAuth 1.0a Token Exchange . . . . . . . . . . 12 | |||
4.3. Failed Exchange . . . . . . . . . . . . . . . . . . . . . 13 | 4.3. Failed Exchange . . . . . . . . . . . . . . . . . . . . . 13 | |||
4.4. SMTP Example of a Failed Negotiation . . . . . . . . . . 14 | 4.4. SMTP Example of a Failed Negotiation . . . . . . . . . . 14 | |||
5. Security Considerations . . . . . . . . . . . . . . . . . . . 14 | 5. Security Considerations . . . . . . . . . . . . . . . . . . . 15 | |||
6. Internationalization Considerations . . . . . . . . . . . . . 16 | 6. Internationalization Considerations . . . . . . . . . . . . . 16 | |||
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16 | 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16 | |||
7.1. SASL Registration . . . . . . . . . . . . . . . . . . . . 16 | 7.1. SASL Registration . . . . . . . . . . . . . . . . . . . . 16 | |||
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 17 | 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 17 | |||
8.1. Normative References . . . . . . . . . . . . . . . . . . 17 | 8.1. Normative References . . . . . . . . . . . . . . . . . . 17 | |||
8.2. Informative References . . . . . . . . . . . . . . . . . 18 | 8.2. Informative References . . . . . . . . . . . . . . . . . 18 | |||
Appendix A. Acknowlegements . . . . . . . . . . . . . . . . . . 18 | Appendix A. Acknowlegements . . . . . . . . . . . . . . . . . . 19 | |||
Appendix B. Document History . . . . . . . . . . . . . . . . . . 18 | Appendix B. Document History . . . . . . . . . . . . . . . . . . 19 | |||
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 21 | Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 22 | |||
1. Introduction | 1. Introduction | |||
OAuth 1.0a [RFC5849] and OAuth 2.0 [RFC6749] are protocol frameworks | OAuth 1.0a [RFC5849] and OAuth 2.0 [RFC6749] are protocol frameworks | |||
that enable a third-party application to obtain limited access to a | that enable a third-party application to obtain limited access to a | |||
protected resource, either on behalf of a resource owner by | protected resource, either on behalf of a resource owner by | |||
orchestrating an approval interaction, or by allowing the third-party | orchestrating an approval interaction, or by allowing the third-party | |||
application to obtain access on its own behalf. | application to obtain access on its own behalf. | |||
The core OAuth 2.0 specification [RFC6749] specifies the interaction | The core OAuth 2.0 specification [RFC6749] specifies the interaction | |||
skipping to change at page 5, line 27 | skipping to change at page 5, line 27 | |||
(F) The resource server validates the access token, and if valid, | (F) The resource server validates the access token, and if valid, | |||
indicates a successful authentication. | indicates a successful authentication. | |||
Again, steps (E) and (F) are not defined in [RFC6749] (but are | Again, steps (E) and (F) are not defined in [RFC6749] (but are | |||
described in, for example, [RFC6750] for the OAuth Bearer Token | described in, for example, [RFC6750] for the OAuth Bearer Token | |||
instead) and are the main functionality specified within this | instead) and are the main functionality specified within this | |||
document. Consequently, the message exchange shown in Figure 1 is | document. Consequently, the message exchange shown in Figure 1 is | |||
the result of this specification. The client will generally need to | the result of this specification. The client will generally need to | |||
determine the authentication endpoints (and perhaps the service | determine the authentication endpoints (and perhaps the service | |||
endpoints) before the OAuth 2.0 protocol exchange messages in steps | endpoints) before the OAuth 2.0 protocol exchange messages in steps | |||
(A)-(D) are executed. The discovery of the resource owner and | (A)-(D) are executed. The discovery of the resource owner, | |||
authorization server endpoints is outside the scope of this | authorization server endpoints, and client registration are outside | |||
specification. The client must discover those endpoints using a | the scope of this specification. The client must discover the | |||
discovery mechanism, such as Webfinger using host-meta [RFC7033]. In | authorization endpoints using a discovery mechanism such as OpenID | |||
band discovery is not tenable if clients support the OAuth 2.0 | Connect Discovery [OpenID.Discovery] or Webfinger using host-meta | |||
password grant. Once credentials are obtained the client proceeds to | [RFC7033]. Once credentials are obtained the client proceeds to | |||
steps (E) and (F) defined in this specification. | steps (E) and (F) defined in this specification. Authorization | |||
endpoints MAY require client registration and generic clients SHOULD | ||||
support the Dynamic Client Registration protocol | ||||
[I-D.ietf-oauth-dyn-reg]. | ||||
OAuth 1.0 follows a similar model but uses a different terminology | OAuth 1.0 follows a similar model but uses a different terminology | |||
and does not separate the resource server from the authorization | and does not separate the resource server from the authorization | |||
server. | server. | |||
2. Terminology | 2. Terminology | |||
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", | The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", | |||
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this | "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this | |||
document are to be interpreted as described in [RFC2119]. | document are to be interpreted as described in [RFC2119]. | |||
skipping to change at page 7, line 35 | skipping to change at page 7, line 37 | |||
protocols are allowed to require an authzid, as are specific server | protocols are allowed to require an authzid, as are specific server | |||
implementations. | implementations. | |||
The following keys and corresponding values are defined in the client | The following keys and corresponding values are defined in the client | |||
response: | response: | |||
auth (REQUIRED): The payload that would be in the HTTP | auth (REQUIRED): The payload that would be in the HTTP | |||
Authorization header if this OAuth exchange was being carried | Authorization header if this OAuth exchange was being carried | |||
out over HTTP. | out over HTTP. | |||
host: Contains the host name to which the client connected, in an | host: Contains the host name to which the client connected. In | |||
HTTP context this is the value of the HTTP Host header. | an HTTP context this is the value of the HTTP Host header. | |||
port: Contains the port number represented as a decimal positive | port: Contains the port number represented as a decimal positive | |||
integer string without leading zeros to which the client | integer string without leading zeros to which the client | |||
connected. | connected. | |||
For OAuth token types such as OAuth 1.0a that use keyed message | For OAuth token types such as OAuth 1.0a that use keyed message | |||
digests the client MUST send host and port number key/values, and the | digests the client MUST send host and port number key/values, and the | |||
server MUST fail an authorization request requiring keyed message | server MUST fail an authorization request requiring keyed message | |||
digests that are not accompanied by host and port values. In OAuth | digests that are not accompanied by host and port values. In OAuth | |||
1.0a for example, the so-called "signature base string calculation" | 1.0a for example, the so-called "signature base string calculation" | |||
skipping to change at page 9, line 32 | skipping to change at page 9, line 32 | |||
single scope is preferred, use of a space separated list of | single scope is preferred, use of a space separated list of | |||
scopes is NOT RECOMMENDED. | scopes is NOT RECOMMENDED. | |||
oauth-configuration (OPTIONAL): The URL for for a document | oauth-configuration (OPTIONAL): The URL for for a document | |||
following the OpenID Provider Configuration Information schema | following the OpenID Provider Configuration Information schema | |||
as described in OpenID Connect Discovery [OpenID.Discovery] | as described in OpenID Connect Discovery [OpenID.Discovery] | |||
section 3 that is appropriate for the user. This document MUST | section 3 that is appropriate for the user. This document MUST | |||
have all OAuth related data elements populated. The server MAY | have all OAuth related data elements populated. The server MAY | |||
return different URLs for users in different domains and the | return different URLs for users in different domains and the | |||
client SHOULD NOT cache a single returned value and assume it | client SHOULD NOT cache a single returned value and assume it | |||
applies for all users/domains that the server suports. | applies for all users/domains that the server suports. The | |||
returned discovery document SHOULD have all data elements | ||||
required by the OpenID Connect Discovery specification | ||||
populated. In addition, the discovery document SHOULD contain | ||||
the 'registration_endpoint' element to learn about the endpoint | ||||
to be used with the Dynamic Client Registration protocol | ||||
[I-D.ietf-oauth-dyn-reg] to obtain the minimum number of | ||||
parameters necessary for the OAuth protocol exchange to | ||||
function. Another comparable discovery or client registration | ||||
mechanism MAY be used if available. | ||||
The use of the 'offline_access' scope, as defined in | ||||
[OpenID.Core] is RECOMMENDED to give clients the capability to | ||||
explicitly request a refresh token. | ||||
If the resource server provides a scope then the client MUST always | If the resource server provides a scope then the client MUST always | |||
request scoped tokens from the token endpoint. If the resource | request scoped tokens from the token endpoint. If the resource | |||
server provides no scope to the client then the client SHOULD presume | server provides no scope to the client then the client SHOULD presume | |||
an empty scope (unscoped token) is required to access the resource. | an empty scope (unscoped token) is required to access the resource. | |||
Since clients may interact with a number of application servers, such | ||||
as email servers and XMPP servers, they need to have a way to | ||||
determine whether dynamic client registration has been performed | ||||
already and whether an already available refresh token can be re-used | ||||
to obtain an access token for the desired resource server. This | ||||
specification RECOMMENDs that a client uses the information in the | ||||
'issue' element to make this determination. | ||||
3.2.3. Completing an Error Message Sequence | 3.2.3. Completing an Error Message Sequence | |||
Section 3.6 of [RFC4422] explicitly prohibits additional information | Section 3.6 of [RFC4422] explicitly prohibits additional information | |||
in an unsuccessful authentication outcome. Therefore, the error | in an unsuccessful authentication outcome. Therefore, the error | |||
message is sent in a normal message. The client MUST then send an | message is sent in a normal message. The client MUST then send an | |||
additional client response consisting of a single %x01 (control A) | additional client response consisting of a single %x01 (control A) | |||
character to the server in order to allow the server to finish the | character to the server in order to allow the server to finish the | |||
exchange. | exchange. | |||
3.3. OAuth Access Token Types using Keyed Message Digests | 3.3. OAuth Access Token Types using Keyed Message Digests | |||
skipping to change at page 13, line 33 | skipping to change at page 13, line 50 | |||
C: t0 CAPABILITY | C: t0 CAPABILITY | |||
S: * CAPABILITY IMAP4rev1 AUTH=OAUTHBEARER SASL-IR IMAP4rev1 Server | S: * CAPABILITY IMAP4rev1 AUTH=OAUTHBEARER SASL-IR IMAP4rev1 Server | |||
Ready | Ready | |||
S: t0 OK Completed | S: t0 OK Completed | |||
C: t1 AUTHENTICATE OAUTHBEARER bixhPXVzZXJAZXhhbXBsZS5jb20sAW | C: t1 AUTHENTICATE OAUTHBEARER bixhPXVzZXJAZXhhbXBsZS5jb20sAW | |||
hvc3Q9c2VydmVyLmV4YW1wbGUuY29tAXBvcnQ9MTQzAWF1dGg9AQE= | hvc3Q9c2VydmVyLmV4YW1wbGUuY29tAXBvcnQ9MTQzAWF1dGg9AQE= | |||
S: + eyJzdGF0dXMiOiJpbnZhbGlkX3Rva2VuIiwic2NvcGUiOiJleGFtcGxl | S: + eyJzdGF0dXMiOiJpbnZhbGlkX3Rva2VuIiwic2NvcGUiOiJleGFtcGxl | |||
X3Njb3BlIiwib3BlbmlkLWNvbmZpZ3VyYXRpb24iOiJodHRwczovL2V4 | X3Njb3BlIiwib3BlbmlkLWNvbmZpZ3VyYXRpb24iOiJodHRwczovL2V4 | |||
YW1wbGUuY29tLy53ZWxsLWtub3duL29wZW5pZC1jb25maWd1cmF0aW9u | YW1wbGUuY29tLy53ZWxsLWtub3duL29wZW5pZC1jb25maWd1cmF0aW9u | |||
In0= | In0= | |||
S: + eyJzdGF0dXMiOiI0MDEiLCJzY29wZSI6ImV4YW1wbGVfc2NvcGUiLCJv | ||||
cGVuaWQtY29uZmlndXJhdGlvbiI6Imh0dHBzOi8vZXhhbXBsZS5jb20v | ||||
LndlbGwta25vd24vb3BlbmlkLWNvbmZpZ3VyYXRpb24ifQ== | ||||
C: + AQ== | C: + AQ== | |||
S: t1 NO SASL authentication failed | S: t1 NO SASL authentication failed | |||
The decoded initial client response is: | The decoded initial client response is: | |||
n,a=user@example.com,^Ahost=server.example.com^A | n,a=user@example.com,^Ahost=server.example.com^A | |||
port=143^Aauth=^A^A | port=143^Aauth=^A^A | |||
The decoded server error response is: | The decoded server error response is: | |||
{ | { | |||
"status":"invalid_token", | "status":"invalid_token", | |||
"scope":"example_scope", | "scope":"example_scope", | |||
skipping to change at page 17, line 4 | skipping to change at page 17, line 17 | |||
SASL mechanism profile: OAUTH10A | SASL mechanism profile: OAUTH10A | |||
Security Considerations: See this document | Security Considerations: See this document | |||
Published Specification: See this document | Published Specification: See this document | |||
For further information: Contact the authors of this document. | For further information: Contact the authors of this document. | |||
Owner/Change controller: the IETF | Owner/Change controller: the IETF | |||
Note: None | Note: None | |||
8. References | 8. References | |||
8.1. Normative References | 8.1. Normative References | |||
[OpenID.Core] | ||||
Sakimura, N., Bradley, J., Jones, M., de Medeiros, B., and | ||||
C. Mortimore, "OpenID Connect Core 1.0", February 2014. | ||||
[OpenID.Discovery] | [OpenID.Discovery] | |||
Sakimura, N., Bradley, J., Jones, M., and E. Jay, "OpenID | Sakimura, N., Bradley, J., Jones, M., and E. Jay, "OpenID | |||
Connect Discovery 1.0", July 2011. | Connect Discovery 1.0", July 2011. | |||
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate | [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate | |||
Requirement Levels", BCP 14, RFC 2119, March 1997. | Requirement Levels", BCP 14, RFC 2119, March 1997. | |||
[RFC3174] Eastlake, D. and P. Jones, "US Secure Hash Algorithm 1 | [RFC3174] Eastlake, D. and P. Jones, "US Secure Hash Algorithm 1 | |||
(SHA1)", RFC 3174, September 2001. | (SHA1)", RFC 3174, September 2001. | |||
skipping to change at page 18, line 7 | skipping to change at page 18, line 21 | |||
April 2010. | April 2010. | |||
[RFC6749] Hardt, D., "The OAuth 2.0 Authorization Framework", RFC | [RFC6749] Hardt, D., "The OAuth 2.0 Authorization Framework", RFC | |||
6749, October 2012. | 6749, October 2012. | |||
[RFC6750] Jones, M. and D. Hardt, "The OAuth 2.0 Authorization | [RFC6750] Jones, M. and D. Hardt, "The OAuth 2.0 Authorization | |||
Framework: Bearer Token Usage", RFC 6750, October 2012. | Framework: Bearer Token Usage", RFC 6750, October 2012. | |||
8.2. Informative References | 8.2. Informative References | |||
[I-D.ietf-oauth-dyn-reg] | ||||
Richer, J., Jones, M., Bradley, J., Machulak, M., and P. | ||||
Hunt, "OAuth 2.0 Dynamic Client Registration Protocol", | ||||
draft-ietf-oauth-dyn-reg-20 (work in progress), August | ||||
2014. | ||||
[I-D.ietf-oauth-json-web-token] | [I-D.ietf-oauth-json-web-token] | |||
Jones, M., Bradley, J., and N. Sakimura, "JSON Web Token | Jones, M., Bradley, J., and N. Sakimura, "JSON Web Token | |||
(JWT)", draft-ietf-oauth-json-web-token-25 (work in | (JWT)", draft-ietf-oauth-json-web-token-30 (work in | |||
progress), July 2014. | progress), October 2014. | |||
[I-D.ietf-oauth-v2-http-mac] | [I-D.ietf-oauth-v2-http-mac] | |||
Richer, J., Mills, W., Tschofenig, H., and P. Hunt, "OAuth | Richer, J., Mills, W., Tschofenig, H., and P. Hunt, "OAuth | |||
2.0 Message Authentication Code (MAC) Tokens", draft-ietf- | 2.0 Message Authentication Code (MAC) Tokens", draft-ietf- | |||
oauth-v2-http-mac-05 (work in progress), January 2014. | oauth-v2-http-mac-05 (work in progress), January 2014. | |||
[RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H., | [RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H., | |||
Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext | Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext | |||
Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999. | Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999. | |||
skipping to change at page 18, line 52 | skipping to change at page 19, line 23 | |||
Williams, Matt Miller, and Benjamin Kaduk. | Williams, Matt Miller, and Benjamin Kaduk. | |||
This document was produced under the chairmanship of Alexey Melnikov, | This document was produced under the chairmanship of Alexey Melnikov, | |||
Tom Yu, Shawn Emery, Josh Howlett, Sam Hartman. The supervising area | Tom Yu, Shawn Emery, Josh Howlett, Sam Hartman. The supervising area | |||
director was Stephen Farrell. | director was Stephen Farrell. | |||
Appendix B. Document History | Appendix B. Document History | |||
[[ to be removed by RFC editor before publication as an RFC ]] | [[ to be removed by RFC editor before publication as an RFC ]] | |||
-17 | ||||
o Last call feedback again. eradicated comma splicing. Removed | ||||
extra server message in example 4.3. | ||||
-16 | -16 | |||
o Last call feedback again. Primarily editorial changes. Corrected | o Last call feedback again. Primarily editorial changes. Corrected | |||
examples. | examples. | |||
-15 | -15 | |||
o Last call feedack on the GS2 stuff being ripped out completely. | o Last call feedack on the GS2 stuff being ripped out completely. | |||
o Removed the "user" parameter and put stuff back into the | o Removed the "user" parameter and put stuff back into the | |||
gs2-header. Call out that the authzid goes in the gs2-header with | gs2-header. Call out that the authzid goes in the gs2-header with | |||
some prose about when it might be required. Very comparable to | some prose about when it might be required. Very comparable to | |||
End of changes. 19 change blocks. | ||||
25 lines changed or deleted | 62 lines changed or added | |||
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