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* UBUNTU: SAUCE: AppArmor: Allow dfa backward compatibility with broken userspaceJohn Johansen2011-08-30
| | | | | | | | | | | | | | | | | | | | | | | Allow broken Lucid userspace tools to load policy, on Maverick kernel. The fix for http://launchpad.net/bugs/581525 blocks Lucid tools from loading policy, this provides compatibility with Lucid tools without reintroducing the bug. The apparmor_parser when compiling policy could generate invalid dfas that did not have sufficient padding to avoid invalid references, when used by the kernel. The kernels check to verify the next/check table size was broken meaning invalid dfas were being created by userspace and not caught. To remain compatible with old tools that are not fixed, pad the loaded dfas next/check table. The dfa's themselves are valid except for the high padding for potentially invalid transitions (high bounds error), which have a maximimum is 256 entries. So just allocate an extra null filled 256 entries for the next/check tables. This will guarentee all bounds are good and invalid transitions go to the null (0) state. Signed-off-by: John Johansen <john.johansen@canonical.com> Signed-off-by: Leann Ogasawara <leann.ogasawara@canonical.com>
* Create Documentation/security/,Randy Dunlap2011-05-19
| | | | | | | | move LSM-, credentials-, and keys-related files from Documentation/ to Documentation/security/, add Documentation/security/00-INDEX, and update all occurrences of Documentation/<moved_file> to Documentation/security/<moved_file>.
* Fix common misspellingsLucas De Marchi2011-03-31
| | | | | | Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
* AppArmor: dfa match engineJohn Johansen2010-08-02
A basic dfa matching engine based off the dfa engine in the Dragon Book. It uses simple row comb compression with a check field. This allows AppArmor to do pattern matching in linear time, and also avoids stack issues that an nfa based engine may have. The dfa engine uses a byte based comparison, with all values being valid. Any potential character encoding are handled user side when the dfa tables are created. By convention AppArmor uses \0 to separate two dependent path matches since \0 is not a valid path character (this is done in the link permission check). The dfa tables are generated in user space and are verified at load time to be internally consistent. There are several future improvements planned for the dfa engine: * The dfa engine may be converted to a hybrid nfa-dfa engine, with a fixed size limited stack. This would allow for size time tradeoffs, by inserting limited nfa states to help control state explosion that can occur with dfas. * The dfa engine may pickup the ability to do limited dynamic variable matching, instead of fixing all variables at policy load time. Signed-off-by: John Johansen <john.johansen@canonical.com> Signed-off-by: James Morris <jmorris@namei.org>