2026-09-18T20:15:06Zhttps://dspace.mit.edu/server/oai/requestoai:dspace.mit.edu:1721.1/167172022-01-13T07:54:29Zcom_1721.1_7582com_1721.1_7581col_1721.1_131022
Barbara Liskov.
Myers, Andrew C. (Andrew Clifford)
Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science
2005-05-19T14:19:57Z
2005-05-19T14:19:57Z
1999
1999
http://hdl.handle.net/1721.1/16717
42648208
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1999.
Includes bibliographical references (p. 169-174) and index.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
The growing use of mobile code in downloaded programs such as applets and servlets has increased interest in robust mechanisms for ensuring privacy and secrecy. Common security mechanisms such as sand boxing and access control are either too restrictive or too weak -- they prevent applications from sharing data usefully, or allow private information to leak. For example, security mechanisms in Java prevent many useful applications while still permitting Trojan horse applets to leak private information. This thesis describes the decentralized label model, a new model of information flow control that protects private data while allowing applications to share data. Unlike previous approaches to privacy protection based on information flow, this label model is decentralized: it allows cooperative computation by mutually distrusting principals, without mediation by highly trusted agents. Cooperative computation is possible because individual principals can declassify their own data without infringing on other principals' privacy. The decentralized label model permits programs using it to be checked statically, which is important for the precise detection of information leaks. This thesis also presents the new language J flow, an extension to the Java programming language that incorporates the decentralized label model and permits static checking of information flows within programs. Variable declarations in J flow programs are annotated with labels that allow the static checker to check programs for information leaks efficiently, in a manner similar to type checking. Often, these labels can be inferred automatically, so annotating programs is not onerous. Dynamic checks also may be used safely when static checks are insufficiently powerful. A compiler has been implemented for the J flow language. Because most checking is performed statically at compile time, the compiler generates code with few additional dynamic tests, improving performance.
by Andrew C. Myers.
Ph.D.
177 p.
883862 bytes
883615 bytes
application/pdf
application/pdf
eng
Massachusetts Institute of Technology
M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.
http://dspace.mit.edu/handle/1721.1/7582
Electrical Engineering and Computer Science
Mostly-static decentralized information flow control
Thesis
application/pdf
false
Publication
unknown
unknown
<Publication xmlns="https://www.openaire.eu/cerif-profile/1.1/" id="16693d4e-72bd-4651-87a9-887917863a01">
<Type xmlns="https://www.openaire.eu/cerif-profile/vocab/COAR_Publication_Types">http://purl.org/coar/resource_type/c_1843</Type>
<Language>eng</Language>
<Title>Mostly-static decentralized information flow control</Title>
<PublishedIn>
<Publication>
</Publication>
</PublishedIn>
<PublicationDate>1999</PublicationDate>
<Authors>
<Author>
<DisplayName>Myers, Andrew C. (Andrew Clifford)</DisplayName>
<Affiliation>
<OrgUnit>
</OrgUnit>
</Affiliation>
</Author>
</Authors>
<Editors>
</Editors>
<Publishers>
<Publisher>
<DisplayName>Massachusetts Institute of Technology</DisplayName>
<OrgUnit />
</Publisher>
</Publishers>
<License>http://dspace.mit.edu/handle/1721.1/7582</License>
<Keyword>Electrical Engineering and Computer Science</Keyword>
<Abstract>The growing use of mobile code in downloaded programs such as applets and servlets has increased interest in robust mechanisms for ensuring privacy and secrecy. Common security mechanisms such as sand boxing and access control are either too restrictive or too weak -- they prevent applications from sharing data usefully, or allow private information to leak. For example, security mechanisms in Java prevent many useful applications while still permitting Trojan horse applets to leak private information. This thesis describes the decentralized label model, a new model of information flow control that protects private data while allowing applications to share data. Unlike previous approaches to privacy protection based on information flow, this label model is decentralized: it allows cooperative computation by mutually distrusting principals, without mediation by highly trusted agents. Cooperative computation is possible because individual principals can declassify their own data without infringing on other principals' privacy. The decentralized label model permits programs using it to be checked statically, which is important for the precise detection of information leaks. This thesis also presents the new language J flow, an extension to the Java programming language that incorporates the decentralized label model and permits static checking of information flows within programs. Variable declarations in J flow programs are annotated with labels that allow the static checker to check programs for information leaks efficiently, in a manner similar to type checking. Often, these labels can be inferred automatically, so annotating programs is not onerous. Dynamic checks also may be used safely when static checks are insufficiently powerful. A compiler has been implemented for the J flow language. Because most checking is performed statically at compile time, the compiler generates code with few additional dynamic tests, improving performance.</Abstract>
<Access xmlns="http://purl.org/coar/access_right"
>
</Access>
</Publication>