Here are some patches to provide some security changes and some container
support:
(1) The mapping from KEY_NEED_* symbols to what is permitted is pushed
further down into the general permissions checking routines and the
LSMs.
More KEY_NEED_* symbols are provided to give finer grained control in
the mapping.
(2) The permissions mask is replaced internally with an ACL that contains
a list of ACEs, each with a specific subject and granted permissions
mask. Potted default ACLs are available for new keys and keyrings.
ACE subjects include:
- The owner of the key (uid)
- The key's group (gid)
- Anyone who possesses the key
- Everyone
- Containers (ie. user_namespaces)
(3) The ACE permissions are split to give finer control. Examples include
splitting the revocation permit from the change-attributes permit,
thereby allowing someone to be granted permission to revoke a key
without allowing them to change the owner; also the ability to join a
keyring is split from the ability to link to it, thereby stopping a
process accessing a keyring by joining it and thus acquiring use of
possessor permits.
This is only accessible through the ACL interface; the old setperm
interface concocts an ACL from what it is given.
(4) A keyctl is provided to grant or remove a grant of one or more permits
to a specific subject. Direct access to the ACL is not permitted, and
the ACL cannot be viewed.
(5) A container keyring is made available on the user-namespace and
created when needed. This is searched by request_key() after it has
searched the normal thread/process/session keyrings, but it can't
normally be accessed from inside the container. The container
manager, however, *can* manipulate the contents of the keyring.
This allows the manager to push keys into the container to allow the
use of authenticated network filesystems without any need for the
denizens inside the container to do anything as the manager can add
and refresh the keys.
The patches can be found on the following branch:
https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/log/?h=keys-acl
David
---
David Howells (1):
keys: Implement a 'container' keyring
Documentation/security/keys/core.rst | 128 ++++-
Documentation/security/keys/request-key.rst | 9 +-
certs/blacklist.c | 9 +-
certs/system_keyring.c | 12 +-
crypto/asymmetric_keys/asymmetric_type.c | 2 +-
drivers/md/dm-crypt.c | 2 +-
drivers/md/dm-verity-verify-sig.c | 3 +-
drivers/nvdimm/security.c | 2 +-
fs/afs/security.c | 2 +-
fs/cifs/cifs_spnego.c | 25 +-
fs/cifs/cifsacl.c | 28 +-
fs/cifs/connect.c | 4 +-
fs/crypto/keyring.c | 29 +-
fs/crypto/keysetup_v1.c | 2 +-
fs/ecryptfs/ecryptfs_kernel.h | 2 +-
fs/ecryptfs/keystore.c | 2 +-
fs/fscache/object-list.c | 2 +-
fs/nfs/nfs4idmap.c | 30 +-
fs/ubifs/auth.c | 2 +-
fs/verity/signature.c | 14 +-
include/linux/key.h | 142 +++--
include/linux/lsm_hook_defs.h | 2 +-
include/linux/lsm_hooks.h | 8 +
include/linux/security.h | 9 +-
include/linux/user_namespace.h | 7 +
include/uapi/linux/keyctl.h | 69 +++
lib/digsig.c | 2 +-
net/ceph/ceph_common.c | 2 +-
net/dns_resolver/dns_key.c | 12 +-
net/dns_resolver/dns_query.c | 15 +-
net/rxrpc/key.c | 19 +-
net/rxrpc/security.c | 2 +-
net/wireless/reg.c | 6 +-
security/integrity/digsig.c | 31 +-
security/integrity/digsig_asymmetric.c | 2 +-
security/integrity/evm/evm_crypto.c | 2 +-
security/integrity/ima/ima_mok.c | 13 +-
security/integrity/integrity.h | 6 +-
.../integrity/platform_certs/platform_keyring.c | 14 +-
security/keys/Kconfig | 11 +
security/keys/compat.c | 5 +
security/keys/dh.c | 7 +-
security/keys/encrypted-keys/encrypted.c | 2 +-
security/keys/encrypted-keys/masterkey_trusted.c | 2 +-
security/keys/gc.c | 2 +-
security/keys/internal.h | 41 +-
security/keys/key.c | 98 ++--
security/keys/keyctl.c | 580 +++++++++++---------
security/keys/keyctl_pkey.c | 17 +-
security/keys/keyring.c | 47 +-
security/keys/permission.c | 600 +++++++++++++++++++--
security/keys/persistent.c | 29 +-
security/keys/proc.c | 27 +-
security/keys/process_keys.c | 137 +++--
security/keys/request_key.c | 49 +-
security/keys/request_key_auth.c | 23 +-
security/security.c | 4 +-
security/selinux/hooks.c | 163 ++++--
security/smack/smack_lsm.c | 90 +++-
59 files changed, 1885 insertions(+), 721 deletions(-)
