Document access control

• US 20070005595A1
• Filed: 06/30/2005
• Published: 01/04/2007
• Est. Priority Date: 06/30/2005
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Google Inc. (Alphabet Inc.)
• Inventors: Gafter, Neal
• Granted Patent: US 7,627,569 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 21/6209 to a single file or object, e.g. in a secure envelope, encrypted and accessed using a key, or with access control rules appended to the object itself
• CPC Class Codes: G06F 21/6218 to a system of files or objects, e.g. local or distributed file system or database
• CPC Class Codes: G06F 2221/2141 Access rights, e.g. capability lists, access control lists, access tables, access matrices

Abstract

Embodiments of this invention control access to documents by identifying a user requesting a document, retrieving a membership list associated with the user, retrieving an access control list (ACL) associated with the document, and intersecting the user'"'"'s membership list and the document'"'"'s ACL to determine if the user has privileges to access to the document. Certain embodiments of this invention filter documents in a search result to return those documents (or a list of those documents) that are accessible to a user.

Claims

1. A method comprising:

associating a user with a first set of aliases;

associating a document with a second set of aliases; and

granting the user access to the document when the first and second sets of aliases have an alias in common.

2. The method of claim 1, wherein associating the user with the first set of aliases comprises mapping the user to aliases in which the user is either a direct or indirect member.

3. The method of claim 1, wherein associating the document with the second set of aliases comprises mapping the document to a predefined access control list.

4. The method of claim 1, wherein the document is one of a web page, an object in a software application or a subset of files shared in an online file-sharing application.

5. A method comprising:

generating for a user a membership list to identify aliases having the user as a direct or indirect member;

assigning to a document in a plurality of documents an access control list (ACL) to identify aliases having access to the document;

receiving a request from the user for access to the document;

in response to the request, retrieving the membership list and the ACL;

intersecting the membership list and the ACL; and

granting the user access to the document when the intersection is not null.

6. The method of claim 5, further comprising invalidating the membership list when the user is added or removed from an alias.

7. The method of claim 5, further comprising invalidating the membership list when an alias containing the user is added or removed from another alias.

8. The method of claim 5, further comprising in response to the invalidation, recomputing the membership list independent of a request from the user.

9. The method of claim 5, further comprising recomputing the membership list in response to request from the user for access to the document or another document in the plurality of documents.

10. The method of claim 5, wherein receiving the request comprises receiving the request over a network.

11. A system comprising:

a memory to store for each of a plurality of users a membership list to indicate aliases to which the user is a direct or indirect member;

an input device to receive from a user a request to search for a document meeting a certain criterion;

a search engine to search for the requested document;

a filter coupled to the search engine to prevent the search engine from returning documents inaccessible to the user, wherein a document is inaccessible to the user when an access control list (ACL) associated with the document fails to share an alias with a membership list associated with the user; and

an output device to transmit to the user a list of documents from the search engine passing the filter.

12. The system of claim 11, wherein the filter prevents the search engine from searching access-restricted documents.

13. The system of claim 11, wherein the filter examines documents identified by the search engine.

14. The system of claim 13, wherein the filter intersects the membership list associated with the user with an ACL associated with a document identified by the search engine to determine if the document is inaccessible by the user.

15. The system of claim 13, wherein the filter does not prevent the search engine from listing in a search results list a document write inaccessible to the user.

16. A machine-readable medium, having stored thereon a set of instructions, which when executed, perform a method comprising of:

defining a first data structure to map documents to at least one access control list (ACL), wherein the ACL is to identify aliases to have access to the documents;

defining a second data structure to map each of the aliases to a list of direct members, wherein each list of direct members is to include at least one of a user or another alias;

defining a third data structure to map each of the direct members to a list of aliases directly containing the direct member;

defining a fourth data structure to map each user to a membership list, wherein the membership list contains aliases to which the user as either a direct or indirect member;

in response to a user request for a document, retrieving a membership list mapping to the user and an ACL mapping to the document; and

granting the user access to the document when the membership list and the ACL have an alias in common.

17. The machine-readable medium of claim 16, wherein the method further comprises invalidating the fourth data structure when either the second or third data structure changes.

18. The machine-readable medium of claim 17, wherein the method further comprises analyzing the third data structure recursively to compute the fourth data structure.

19. The machine-readable medium of claim 17, wherein the method further comprises recomputing the fourth data structure when the first, second or third data structure changes.

20. The machine-readable medium of claim 17, wherein granting the user access to the document comprises returning a link to the document.