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2013-10-26ima: new templates management mechanismRoberto Sassu2-0/+89
The original 'ima' template is fixed length, containing the filedata hash and pathname. The filedata hash is limited to 20 bytes (md5/sha1). The pathname is a null terminated string, limited to 255 characters. To overcome these limitations and to add additional file metadata, it is necessary to extend the current version of IMA by defining additional templates. The main reason to introduce this feature is that, each time a new template is defined, the functions that generate and display the measurement list would include the code for handling a new format and, thus, would significantly grow over time. This patch set solves this problem by separating the template management from the remaining IMA code. The core of this solution is the definition of two new data structures: a template descriptor, to determine which information should be included in the measurement list, and a template field, to generate and display data of a given type. To define a new template field, developers define the field identifier and implement two functions, init() and show(), respectively to generate and display measurement entries. Initially, this patch set defines the following template fields (support for additional data types will be added later):  - 'd': the digest of the event (i.e. the digest of a measured file),         calculated with the SHA1 or MD5 hash algorithm;  - 'n': the name of the event (i.e. the file name), with size up to         255 bytes;  - 'd-ng': the digest of the event, calculated with an arbitrary hash            algorithm (field format: [<hash algo>:]digest, where the digest            prefix is shown only if the hash algorithm is not SHA1 or MD5);  - 'n-ng': the name of the event, without size limitations. Defining a new template descriptor requires specifying the template format, a string of field identifiers separated by the '|' character. This patch set defines the following template descriptors:  - "ima": its format is 'd|n';  - "ima-ng" (default): its format is 'd-ng|n-ng' Further details about the new template architecture can be found in Documentation/security/IMA-templates.txt. Changelog: - don't defer calling ima_init_template() - Mimi - don't define ima_lookup_template_desc() until used - Mimi - squashed with documentation patch - Mimi Signed-off-by: Roberto Sassu <roberto.sassu@polito.it> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2013-09-24KEYS: Define a __key_get() wrapper to use rather than atomic_inc()David Howells1-5/+8
Define a __key_get() wrapper to use rather than atomic_inc() on the key usage count as this makes it easier to hook in refcount error debugging. Signed-off-by: David Howells <dhowells@redhat.com>
2013-09-24KEYS: Use bool in make_key_ref() and is_key_possessed()David Howells1-4/+3
Make make_key_ref() take a bool possession parameter and make is_key_possessed() return a bool. Signed-off-by: David Howells <dhowells@redhat.com>
2013-03-20Smack: add support for modification of existing rulesRafal Krypa1-0/+11
Rule modifications are enabled via /smack/change-rule. Format is as follows: "Subject Object rwaxt rwaxt" First two strings are subject and object labels up to 255 characters. Third string contains permissions to enable. Fourth string contains permissions to disable. All unmentioned permissions will be left unchanged. If no rule previously existed, it will be created. Targeted for git://git.gitorious.org/smack-next/kernel.git Signed-off-by: Rafal Krypa <r.krypa@samsung.com>
2012-12-18Documentation: fix Documentation/security/00-INDEXJarkko Sakkinen1-0/+2
keys-ecryptfs.txt was missing from 00-INDEX. Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-02Merge branch 'modsign-keys-devel' into security-next-keysDavid Howells1-1/+49
Signed-off-by: David Howells <dhowells@redhat.com>
2012-10-02KEYS: Use keyring_alloc() to create special keyringsDavid Howells1-0/+17
Use keyring_alloc() to create special keyrings now that it has a permissions parameter rather than using key_alloc() + key_instantiate_and_link(). Also document and export keyring_alloc() so that modules can use it too. Signed-off-by: David Howells <dhowells@redhat.com>
2012-09-26Documentation: Update git repository URL for Smack userland toolsDaniel Wagner1-4/+3
The userland git repository has been moved to a new place. Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de> Cc: Casey Schaufler <casey@schaufler-ca.com> Cc: Rob Landley <rob@landley.net> Cc: linux-security-module@vger.kernel.org Cc: lkml@vger.kernel.org
2012-09-18Smack: implement revoking all rules for a subject labelRafal Krypa1-0/+3
Add /smack/revoke-subject special file. Writing a SMACK label to this file will set the access to '-' for all access rules with that subject label. Targeted for git://git.gitorious.org/smack-next/kernel.git Signed-off-by: Rafal Krypa <r.krypa@samsung.com>
2012-09-13KEYS: Add payload preparsing opportunity prior to key instantiate or updateDavid Howells1-1/+49
Give the key type the opportunity to preparse the payload prior to the instantiation and update routines being called. This is done with the provision of two new key type operations: int (*preparse)(struct key_preparsed_payload *prep); void (*free_preparse)(struct key_preparsed_payload *prep); If the first operation is present, then it is called before key creation (in the add/update case) or before the key semaphore is taken (in the update and instantiate cases). The second operation is called to clean up if the first was called. preparse() is given the opportunity to fill in the following structure: struct key_preparsed_payload { char *description; void *type_data[2]; void *payload; const void *data; size_t datalen; size_t quotalen; }; Before the preparser is called, the first three fields will have been cleared, the payload pointer and size will be stored in data and datalen and the default quota size from the key_type struct will be stored into quotalen. The preparser may parse the payload in any way it likes and may store data in the type_data[] and payload fields for use by the instantiate() and update() ops. The preparser may also propose a description for the key by attaching it as a string to the description field. This can be used by passing a NULL or "" description to the add_key() system call or the key_create_or_update() function. This cannot work with request_key() as that required the description to tell the upcall about the key to be created. This, for example permits keys that store PGP public keys to generate their own name from the user ID and public key fingerprint in the key. The instantiate() and update() operations are then modified to look like this: int (*instantiate)(struct key *key, struct key_preparsed_payload *prep); int (*update)(struct key *key, struct key_preparsed_payload *prep); and the new payload data is passed in *prep, whether or not it was preparsed. Signed-off-by: David Howells <dhowells@redhat.com>
2012-08-10Yama: higher restrictions should block PTRACE_TRACEMEKees Cook1-7/+7
The higher ptrace restriction levels should be blocking even PTRACE_TRACEME requests. The comments in the LSM documentation are misleading about when the checks happen (the parent does not go through security_ptrace_access_check() on a PTRACE_TRACEME call). Signed-off-by: Kees Cook <keescook@chromium.org> Cc: stable@vger.kernel.org # 3.5.x and later Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-05-15Smack: allow for significantly longer Smack labels v4Casey Schaufler1-40/+164
V4 updated to current linux-security#next Targeted for git://gitorious.org/smack-next/kernel.git Modern application runtime environments like to use naming schemes that are structured and generated without human intervention. Even though the Smack limit of 23 characters for a label name is perfectly rational for human use there have been complaints that the limit is a problem in environments where names are composed from a set or sources, including vendor, author, distribution channel and application name. Names like softwarehouse-pgwodehouse-coolappstore-mellowmuskrats are becoming harder to avoid. This patch introduces long label support in Smack. Labels are now limited to 255 characters instead of the old 23. The primary reason for limiting the labels to 23 characters was so they could be directly contained in CIPSO category sets. This is still done were possible, but for labels that are too large a mapping is required. This is perfectly safe for communication that stays "on the box" and doesn't require much coordination between boxes beyond what would have been required to keep label names consistent. The bulk of this patch is in smackfs, adding and updating administrative interfaces. Because existing APIs can't be changed new ones that do much the same things as old ones have been introduced. The Smack specific CIPSO data representation has been removed and replaced with the data format used by netlabel. The CIPSO header is now computed when a label is imported rather than on use. This results in improved IP performance. The smack label is now allocated separately from the containing structure, allowing for larger strings. Four new /smack interfaces have been introduced as four of the old interfaces strictly required labels be specified in fixed length arrays. The access interface is supplemented with the check interface: access "Subject Object rwxat" access2 "Subject Object rwaxt" The load interface is supplemented with the rules interface: load "Subject Object rwxat" load2 "Subject Object rwaxt" The load-self interface is supplemented with the self-rules interface: load-self "Subject Object rwxat" load-self2 "Subject Object rwaxt" The cipso interface is supplemented with the wire interface: cipso "Subject lvl cnt c1 c2 ..." cipso2 "Subject lvl cnt c1 c2 ..." The old interfaces are maintained for compatibility. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2012-05-11KEYS: Add invalidation supportDavid Howells1-0/+17
Add support for invalidating a key - which renders it immediately invisible to further searches and causes the garbage collector to immediately wake up, remove it from keyrings and then destroy it when it's no longer referenced. It's better not to do this with keyctl_revoke() as that marks the key to start returning -EKEYREVOKED to searches when what is actually desired is to have the key refetched. To invalidate a key the caller must be granted SEARCH permission by the key. This may be too strict. It may be better to also permit invalidation if the caller has any of READ, WRITE or SETATTR permission. The primary use for this is to evict keys that are cached in special keyrings, such as the DNS resolver or an ID mapper. Signed-off-by: David Howells <dhowells@redhat.com>
2012-05-04Merge tag 'v3.4-rc5' into nextJames Morris1-1/+13
Linux 3.4-rc5 Merge to pull in prerequisite change for Smack: 86812bb0de1a3758dc6c7aa01a763158a7c0638a Requested by Casey.
2012-04-25keys: update the documentation with info about "logon" keysJeff Layton1-1/+13
Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Jeff Layton <jlayton@redhat.com>
2012-04-19Yama: add additional ptrace scopesKees Cook1-1/+9
This expands the available Yama ptrace restrictions to include two more modes. Mode 2 requires CAP_SYS_PTRACE for PTRACE_ATTACH, and mode 3 completely disables PTRACE_ATTACH (and locks the sysctl). Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-03-22Merge branch 'next' of ↵Linus Torvalds3-0/+71
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security subsystem updates for 3.4 from James Morris: "The main addition here is the new Yama security module from Kees Cook, which was discussed at the Linux Security Summit last year. Its purpose is to collect miscellaneous DAC security enhancements in one place. This also marks a departure in policy for LSM modules, which were previously limited to being standalone access control systems. Chromium OS is using Yama, and I believe there are plans for Ubuntu, at least. This patchset also includes maintenance updates for AppArmor, TOMOYO and others." Fix trivial conflict in <net/sock.h> due to the jumo_label->static_key rename. * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (38 commits) AppArmor: Fix location of const qualifier on generated string tables TOMOYO: Return error if fails to delete a domain AppArmor: add const qualifiers to string arrays AppArmor: Add ability to load extended policy TOMOYO: Return appropriate value to poll(). AppArmor: Move path failure information into aa_get_name and rename AppArmor: Update dfa matching routines. AppArmor: Minor cleanup of d_namespace_path to consolidate error handling AppArmor: Retrieve the dentry_path for error reporting when path lookup fails AppArmor: Add const qualifiers to generated string tables AppArmor: Fix oops in policy unpack auditing AppArmor: Fix error returned when a path lookup is disconnected KEYS: testing wrong bit for KEY_FLAG_REVOKED TOMOYO: Fix mount flags checking order. security: fix ima kconfig warning AppArmor: Fix the error case for chroot relative path name lookup AppArmor: fix mapping of META_READ to audit and quiet flags AppArmor: Fix underflow in xindex calculation AppArmor: Fix dropping of allowed operations that are force audited AppArmor: Add mising end of structure test to caps unpacking ...
2012-03-07Documentation: Fix multiple typo in DocumentationMasanari Iida3-3/+3
Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-02-16Yama: add PR_SET_PTRACER_ANYKees Cook1-1/+6
For a process to entirely disable Yama ptrace restrictions, it can use the special PR_SET_PTRACER_ANY pid to indicate that any otherwise allowed process may ptrace it. This is stronger than calling PR_SET_PTRACER with pid "1" because it includes processes in external pid namespaces. This is currently needed by the Chrome renderer, since its crash handler (Breakpad) runs external to the renderer's pid namespace. Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: James Morris <jmorris@namei.org>
2012-02-10security: Yama LSMKees Cook2-0/+62
This adds the Yama Linux Security Module to collect DAC security improvements (specifically just ptrace restrictions for now) that have existed in various forms over the years and have been carried outside the mainline kernel by other Linux distributions like Openwall and grsecurity. Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: John Johansen <john.johansen@canonical.com> Signed-off-by: James Morris <jmorris@namei.org>
2012-01-19KEYS: Allow special keyrings to be clearedDavid Howells1-0/+4
The kernel contains some special internal keyrings, for instance the DNS resolver keyring : 2a93faf1 I----- 1 perm 1f030000 0 0 keyring .dns_resolver: empty It would occasionally be useful to allow the contents of such keyrings to be flushed by root (cache invalidation). Allow a flag to be set on a keyring to mark that someone possessing the sysadmin capability can clear the keyring, even without normal write access to the keyring. Set this flag on the special keyrings created by the DNS resolver, the NFS identity mapper and the CIFS identity mapper. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Jeff Layton <jlayton@redhat.com> Acked-by: Steve Dickson <steved@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2011-11-16Merge branch 'master'; commit 'v3.2-rc2' into nextJames Morris1-1/+2
2011-11-16Documentation: clarify the purpose of LSMsKees Cook3-3/+39
Clarify the purpose of the LSM interface with some brief examples and pointers to additional documentation. Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: James Morris <jmorris@namei.org>
2011-09-27doc: fix broken referencesPaul Bolle1-1/+2
There are numerous broken references to Documentation files (in other Documentation files, in comments, etc.). These broken references are caused by typo's in the references, and by renames or removals of the Documentation files. Some broken references are simply odd. Fix these broken references, sometimes by dropping the irrelevant text they were part of. Signed-off-by: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-06-30encrypted-keys: move ecryptfs documentation to proper locationMimi Zohar1-0/+68
Move keys-ecryptfs.txt to Documentation/security. Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
2011-06-27encrypted-keys: add ecryptfs format supportRoberto Sassu1-2/+4
The 'encrypted' key type defines its own payload format which contains a symmetric key randomly generated that cannot be used directly to mount an eCryptfs filesystem, because it expects an authentication token structure. This patch introduces the new format 'ecryptfs' that allows to store an authentication token structure inside the encrypted key payload containing a randomly generated symmetric key, as the same for the format 'default'. More details about the usage of encrypted keys with the eCryptfs filesystem can be found in the file 'Documentation/keys-ecryptfs.txt'. Signed-off-by: Roberto Sassu <roberto.sassu@polito.it> Acked-by: Gianluca Ramunno <ramunno@polito.it> Acked-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2011-06-27encrypted-keys: add key format supportRoberto Sassu1-18/+30
This patch introduces a new parameter, called 'format', that defines the format of data stored by encrypted keys. The 'default' format identifies encrypted keys containing only the symmetric key, while other formats can be defined to support additional information. The 'format' parameter is written in the datablob produced by commands 'keyctl print' or 'keyctl pipe' and is integrity protected by the HMAC. Signed-off-by: Roberto Sassu <roberto.sassu@polito.it> Acked-by: Gianluca Ramunno <ramunno@polito.it> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2011-05-20Create Documentation/security/,Randy Dunlap9-0/+2898
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>.