1. 23 7月, 2014 2 次提交
  2. 24 9月, 2013 2 次提交
  3. 08 10月, 2012 1 次提交
    • D
      KEYS: Add payload preparsing opportunity prior to key instantiate or update · cf7f601c
      David Howells 提交于
      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: NDavid Howells <dhowells@redhat.com>
      Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      cf7f601c
  4. 03 10月, 2012 1 次提交
  5. 13 9月, 2012 1 次提交
    • D
      KEYS: Add payload preparsing opportunity prior to key instantiate or update · d4f65b5d
      David Howells 提交于
      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: NDavid Howells <dhowells@redhat.com>
      d4f65b5d
  6. 11 5月, 2012 1 次提交
    • D
      KEYS: Add invalidation support · fd75815f
      David Howells 提交于
      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: NDavid Howells <dhowells@redhat.com>
      fd75815f
  7. 26 4月, 2012 1 次提交
  8. 07 3月, 2012 1 次提交
  9. 19 1月, 2012 1 次提交
  10. 20 5月, 2011 1 次提交
    • R
      Create Documentation/security/, · d410fa4e
      Randy Dunlap 提交于
      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>.
      d410fa4e
  11. 08 3月, 2011 3 次提交
  12. 02 9月, 2009 2 次提交
    • D
      KEYS: Add a keyctl to install a process's session keyring on its parent [try #6] · ee18d64c
      David Howells 提交于
      Add a keyctl to install a process's session keyring onto its parent.  This
      replaces the parent's session keyring.  Because the COW credential code does
      not permit one process to change another process's credentials directly, the
      change is deferred until userspace next starts executing again.  Normally this
      will be after a wait*() syscall.
      
      To support this, three new security hooks have been provided:
      cred_alloc_blank() to allocate unset security creds, cred_transfer() to fill in
      the blank security creds and key_session_to_parent() - which asks the LSM if
      the process may replace its parent's session keyring.
      
      The replacement may only happen if the process has the same ownership details
      as its parent, and the process has LINK permission on the session keyring, and
      the session keyring is owned by the process, and the LSM permits it.
      
      Note that this requires alteration to each architecture's notify_resume path.
      This has been done for all arches barring blackfin, m68k* and xtensa, all of
      which need assembly alteration to support TIF_NOTIFY_RESUME.  This allows the
      replacement to be performed at the point the parent process resumes userspace
      execution.
      
      This allows the userspace AFS pioctl emulation to fully emulate newpag() and
      the VIOCSETTOK and VIOCSETTOK2 pioctls, all of which require the ability to
      alter the parent process's PAG membership.  However, since kAFS doesn't use
      PAGs per se, but rather dumps the keys into the session keyring, the session
      keyring of the parent must be replaced if, for example, VIOCSETTOK is passed
      the newpag flag.
      
      This can be tested with the following program:
      
      	#include <stdio.h>
      	#include <stdlib.h>
      	#include <keyutils.h>
      
      	#define KEYCTL_SESSION_TO_PARENT	18
      
      	#define OSERROR(X, S) do { if ((long)(X) == -1) { perror(S); exit(1); } } while(0)
      
      	int main(int argc, char **argv)
      	{
      		key_serial_t keyring, key;
      		long ret;
      
      		keyring = keyctl_join_session_keyring(argv[1]);
      		OSERROR(keyring, "keyctl_join_session_keyring");
      
      		key = add_key("user", "a", "b", 1, keyring);
      		OSERROR(key, "add_key");
      
      		ret = keyctl(KEYCTL_SESSION_TO_PARENT);
      		OSERROR(ret, "KEYCTL_SESSION_TO_PARENT");
      
      		return 0;
      	}
      
      Compiled and linked with -lkeyutils, you should see something like:
      
      	[dhowells@andromeda ~]$ keyctl show
      	Session Keyring
      	       -3 --alswrv   4043  4043  keyring: _ses
      	355907932 --alswrv   4043    -1   \_ keyring: _uid.4043
      	[dhowells@andromeda ~]$ /tmp/newpag
      	[dhowells@andromeda ~]$ keyctl show
      	Session Keyring
      	       -3 --alswrv   4043  4043  keyring: _ses
      	1055658746 --alswrv   4043  4043   \_ user: a
      	[dhowells@andromeda ~]$ /tmp/newpag hello
      	[dhowells@andromeda ~]$ keyctl show
      	Session Keyring
      	       -3 --alswrv   4043  4043  keyring: hello
      	340417692 --alswrv   4043  4043   \_ user: a
      
      Where the test program creates a new session keyring, sticks a user key named
      'a' into it and then installs it on its parent.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      ee18d64c
    • D
      KEYS: Add garbage collection for dead, revoked and expired keys. [try #6] · 5d135440
      David Howells 提交于
      Add garbage collection for dead, revoked and expired keys.  This involved
      erasing all links to such keys from keyrings that point to them.  At that
      point, the key will be deleted in the normal manner.
      
      Keyrings from which garbage collection occurs are shrunk and their quota
      consumption reduced as appropriate.
      
      Dead keys (for which the key type has been removed) will be garbage collected
      immediately.
      
      Revoked and expired keys will hang around for a number of seconds, as set in
      /proc/sys/kernel/keys/gc_delay before being automatically removed.  The default
      is 5 minutes.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      5d135440
  13. 27 7月, 2008 1 次提交
  14. 29 4月, 2008 3 次提交
    • D
      keys: make the keyring quotas controllable through /proc/sys · 0b77f5bf
      David Howells 提交于
      Make the keyring quotas controllable through /proc/sys files:
      
       (*) /proc/sys/kernel/keys/root_maxkeys
           /proc/sys/kernel/keys/root_maxbytes
      
           Maximum number of keys that root may have and the maximum total number of
           bytes of data that root may have stored in those keys.
      
       (*) /proc/sys/kernel/keys/maxkeys
           /proc/sys/kernel/keys/maxbytes
      
           Maximum number of keys that each non-root user may have and the maximum
           total number of bytes of data that each of those users may have stored in
           their keys.
      
      Also increase the quotas as a number of people have been complaining that it's
      not big enough.  I'm not sure that it's big enough now either, but on the
      other hand, it can now be set in /etc/sysctl.conf.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Cc: <kwc@citi.umich.edu>
      Cc: <arunsr@cse.iitk.ac.in>
      Cc: <dwalsh@redhat.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      0b77f5bf
    • D
      keys: add keyctl function to get a security label · 70a5bb72
      David Howells 提交于
      Add a keyctl() function to get the security label of a key.
      
      The following is added to Documentation/keys.txt:
      
       (*) Get the LSM security context attached to a key.
      
      	long keyctl(KEYCTL_GET_SECURITY, key_serial_t key, char *buffer,
      		    size_t buflen)
      
           This function returns a string that represents the LSM security context
           attached to a key in the buffer provided.
      
           Unless there's an error, it always returns the amount of data it could
           produce, even if that's too big for the buffer, but it won't copy more
           than requested to userspace. If the buffer pointer is NULL then no copy
           will take place.
      
           A NUL character is included at the end of the string if the buffer is
           sufficiently big.  This is included in the returned count.  If no LSM is
           in force then an empty string will be returned.
      
           A process must have view permission on the key for this function to be
           successful.
      
      [akpm@linux-foundation.org: declare keyctl_get_security()]
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NStephen Smalley <sds@tycho.nsa.gov>
      Cc: Paul Moore <paul.moore@hp.com>
      Cc: Chris Wright <chrisw@sous-sol.org>
      Cc: James Morris <jmorris@namei.org>
      Cc: Kevin Coffman <kwc@citi.umich.edu>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      70a5bb72
    • D
      keys: allow the callout data to be passed as a blob rather than a string · 4a38e122
      David Howells 提交于
      Allow the callout data to be passed as a blob rather than a string for
      internal kernel services that call any request_key_*() interface other than
      request_key().  request_key() itself still takes a NUL-terminated string.
      
      The functions that change are:
      
      	request_key_with_auxdata()
      	request_key_async()
      	request_key_async_with_auxdata()
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Cc: Paul Moore <paul.moore@hp.com>
      Cc: Chris Wright <chrisw@sous-sol.org>
      Cc: Stephen Smalley <sds@tycho.nsa.gov>
      Cc: James Morris <jmorris@namei.org>
      Cc: Kevin Coffman <kwc@citi.umich.edu>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      4a38e122
  15. 17 10月, 2007 1 次提交
    • D
      KEYS: Make request_key() and co fundamentally asynchronous · 76181c13
      David Howells 提交于
      Make request_key() and co fundamentally asynchronous to make it easier for
      NFS to make use of them.  There are now accessor functions that do
      asynchronous constructions, a wait function to wait for construction to
      complete, and a completion function for the key type to indicate completion
      of construction.
      
      Note that the construction queue is now gone.  Instead, keys under
      construction are linked in to the appropriate keyring in advance, and that
      anyone encountering one must wait for it to be complete before they can use
      it.  This is done automatically for userspace.
      
      The following auxiliary changes are also made:
      
       (1) Key type implementation stuff is split from linux/key.h into
           linux/key-type.h.
      
       (2) AF_RXRPC provides a way to allocate null rxrpc-type keys so that AFS does
           not need to call key_instantiate_and_link() directly.
      
       (3) Adjust the debugging macros so that they're -Wformat checked even if
           they are disabled, and make it so they can be enabled simply by defining
           __KDEBUG to be consistent with other code of mine.
      
       (3) Documentation.
      
      [alan@lxorguk.ukuu.org.uk: keys: missing word in documentation]
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Signed-off-by: NAlan Cox <alan@redhat.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      76181c13
  16. 01 8月, 2007 1 次提交
  17. 27 4月, 2007 1 次提交
  18. 30 11月, 2006 1 次提交
  19. 04 10月, 2006 3 次提交
  20. 30 6月, 2006 1 次提交
  21. 27 6月, 2006 2 次提交
  22. 23 6月, 2006 2 次提交
    • D
      [PATCH] Keys: Fix race between two instantiators of a key · 04c567d9
      David Howells 提交于
      Add a revocation notification method to the key type and calls it whilst
      the key's semaphore is still write-locked after setting the revocation
      flag.
      
      The patch then uses this to maintain a reference on the task_struct of the
      process that calls request_key() for as long as the authorisation key
      remains unrevoked.
      
      This fixes a potential race between two processes both of which have
      assumed the authority to instantiate a key (one may have forked the other
      for example).  The problem is that there's no locking around the check for
      revocation of the auth key and the use of the task_struct it points to, nor
      does the auth key keep a reference on the task_struct.
      
      Access to the "context" pointer in the auth key must thenceforth be done
      with the auth key semaphore held.  The revocation method is called with the
      target key semaphore held write-locked and the search of the context
      process's keyrings is done with the auth key semaphore read-locked.
      
      The check for the revocation state of the auth key just prior to searching
      it is done after the auth key is read-locked for the search.  This ensures
      that the auth key can't be revoked between the check and the search.
      
      The revocation notification method is added so that the context task_struct
      can be released as soon as instantiation happens rather than waiting for
      the auth key to be destroyed, thus avoiding the unnecessary pinning of the
      requesting process.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      04c567d9
    • M
      [PATCH] selinux: add hooks for key subsystem · d720024e
      Michael LeMay 提交于
      Introduce SELinux hooks to support the access key retention subsystem
      within the kernel.  Incorporate new flask headers from a modified version
      of the SELinux reference policy, with support for the new security class
      representing retained keys.  Extend the "key_alloc" security hook with a
      task parameter representing the intended ownership context for the key
      being allocated.  Attach security information to root's default keyrings
      within the SELinux initialization routine.
      
      Has passed David's testsuite.
      Signed-off-by: NMichael LeMay <mdlemay@epoch.ncsc.mil>
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      Acked-by: NChris Wright <chrisw@sous-sol.org>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      d720024e
  23. 09 1月, 2006 3 次提交
    • D
      [PATCH] keys: Permit running process to instantiate keys · b5f545c8
      David Howells 提交于
      Make it possible for a running process (such as gssapid) to be able to
      instantiate a key, as was requested by Trond Myklebust for NFS4.
      
      The patch makes the following changes:
      
       (1) A new, optional key type method has been added. This permits a key type
           to intercept requests at the point /sbin/request-key is about to be
           spawned and do something else with them - passing them over the
           rpc_pipefs files or netlink sockets for instance.
      
           The uninstantiated key, the authorisation key and the intended operation
           name are passed to the method.
      
       (2) The callout_info is no longer passed as an argument to /sbin/request-key
           to prevent unauthorised viewing of this data using ps or by looking in
           /proc/pid/cmdline.
      
           This means that the old /sbin/request-key program will not work with the
           patched kernel as it will expect to see an extra argument that is no
           longer there.
      
           A revised keyutils package will be made available tomorrow.
      
       (3) The callout_info is now attached to the authorisation key. Reading this
           key will retrieve the information.
      
       (4) A new field has been added to the task_struct. This holds the
           authorisation key currently active for a thread. Searches now look here
           for the caller's set of keys rather than looking for an auth key in the
           lowest level of the session keyring.
      
           This permits a thread to be servicing multiple requests at once and to
           switch between them. Note that this is per-thread, not per-process, and
           so is usable in multithreaded programs.
      
           The setting of this field is inherited across fork and exec.
      
       (5) A new keyctl function (KEYCTL_ASSUME_AUTHORITY) has been added that
           permits a thread to assume the authority to deal with an uninstantiated
           key. Assumption is only permitted if the authorisation key associated
           with the uninstantiated key is somewhere in the thread's keyrings.
      
           This function can also clear the assumption.
      
       (6) A new magic key specifier has been added to refer to the currently
           assumed authorisation key (KEY_SPEC_REQKEY_AUTH_KEY).
      
       (7) Instantiation will only proceed if the appropriate authorisation key is
           assumed first. The assumed authorisation key is discarded if
           instantiation is successful.
      
       (8) key_validate() is moved from the file of request_key functions to the
           file of permissions functions.
      
       (9) The documentation is updated.
      
      From: <Valdis.Kletnieks@vt.edu>
      
          Build fix.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
      Cc: Alexander Zangerl <az@bond.edu.au>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      b5f545c8
    • D
      [PATCH] keys: Discard duplicate keys from a keyring on link · cab8eb59
      David Howells 提交于
      Cause any links within a keyring to keys that match a key to be linked into
      that keyring to be discarded as a link to the new key is added.  The match is
      contingent on the type and description strings being the same.
      
      This permits requests, adds and searches to displace negative, expired,
      revoked and dead keys easily.  After some discussion it was concluded that
      duplicate valid keys should probably be discarded also as they would otherwise
      hide the new key.
      
      Since request_key() is intended to be the primary method by which keys are
      added to a keyring, duplicate valid keys wouldn't be an issue there as that
      function would return an existing match in preference to creating a new key.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
      Cc: Alexander Zangerl <az@bond.edu.au>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      cab8eb59
    • D
      [PATCH] keys: Permit key expiry time to be set · 017679c4
      David Howells 提交于
      Add a new keyctl function that allows the expiry time to be set on a key or
      removed from a key, provided the caller has attribute modification access.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
      Cc: Alexander Zangerl <az@bond.edu.au>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      017679c4
  24. 07 1月, 2006 1 次提交
  25. 31 10月, 2005 1 次提交
    • D
      [PATCH] Keys: Add LSM hooks for key management [try #3] · 29db9190
      David Howells 提交于
      The attached patch adds LSM hooks for key management facilities. The notable
      changes are:
      
       (1) The key struct now supports a security pointer for the use of security
           modules. This will permit key labelling and restrictions on which
           programs may access a key.
      
       (2) Security modules get a chance to note (or abort) the allocation of a key.
      
       (3) The key permission checking can now be enhanced by the security modules;
           the permissions check consults LSM if all other checks bear out.
      
       (4) The key permissions checking functions now return an error code rather
           than a boolean value.
      
       (5) An extra permission has been added to govern the modification of
           attributes (UID, GID, permissions).
      
      Note that there isn't an LSM hook specifically for each keyctl() operation,
      but rather the permissions hook allows control of individual operations based
      on the permission request bits.
      
      Key management access control through LSM is enabled by automatically if both
      CONFIG_KEYS and CONFIG_SECURITY are enabled.
      
      This should be applied on top of the patch ensubjected:
      
      	[PATCH] Keys: Possessor permissions should be additive
      Signed-Off-By: NDavid Howells <dhowells@redhat.com>
      Signed-off-by: NChris Wright <chrisw@osdl.org>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      29db9190
  26. 09 10月, 2005 1 次提交
  27. 29 9月, 2005 1 次提交
    • D
      [PATCH] Keys: Add possessor permissions to keys [try #3] · 664cceb0
      David Howells 提交于
      The attached patch adds extra permission grants to keys for the possessor of a
      key in addition to the owner, group and other permissions bits. This makes
      SUID binaries easier to support without going as far as labelling keys and key
      targets using the LSM facilities.
      
      This patch adds a second "pointer type" to key structures (struct key_ref *)
      that can have the bottom bit of the address set to indicate the possession of
      a key. This is propagated through searches from the keyring to the discovered
      key. It has been made a separate type so that the compiler can spot attempts
      to dereference a potentially incorrect pointer.
      
      The "possession" attribute can't be attached to a key structure directly as
      it's not an intrinsic property of a key.
      
      Pointers to keys have been replaced with struct key_ref *'s wherever
      possession information needs to be passed through.
      
      This does assume that the bottom bit of the pointer will always be zero on
      return from kmem_cache_alloc().
      
      The key reference type has been made into a typedef so that at least it can be
      located in the sources, even though it's basically a pointer to an undefined
      type. I've also renamed the accessor functions to be more useful, and all
      reference variables should now end in "_ref".
      Signed-Off-By: NDavid Howells <dhowells@redhat.com>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      664cceb0