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* libnvdimm/security: Consolidate 'security' operationsDan Williams2019-08-291-4/+86
| | | | | | | | | | | | | | The security operations are exported from libnvdimm/security.c to libnvdimm/dimm_devs.c, and libnvdimm/security.c is optionally compiled based on the CONFIG_NVDIMM_KEYS config symbol. Rather than export the operations across compile objects, just move the __security_store() entry point to live with the helpers. Acked-by: Jeff Moyer <jmoyer@redhat.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/156686730515.184120.10522747907309996674.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* libnvdimm/security: Tighten scope of nvdimm->busy vs security operationsDan Williams2019-08-291-10/+0
| | | | | | | | | | | | | | | | | | | | An attempt to freeze DIMMs currently runs afoul of default blocking of all security operations in the entry to the 'store' routine for the 'security' sysfs attribute. The blanket blocking of all security operations while the DIMM is in active use in a region is too restrictive. The only security operations that need to be aware of the ->busy state are those that mutate the state of data, i.e. erase and overwrite. Refactor the ->busy checks to be applied at the entry common entry point in __security_store() rather than each of the helper routines to enable freeze to be run regardless of busy state. Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Link: https://lore.kernel.org/r/156686729996.184120.3458026302402493937.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* libnvdimm/security: Introduce a 'frozen' attributeDan Williams2019-08-291-52/+47
| | | | | | | | | | | | | | | | | | | | | | | | | In the process of debugging a system with an NVDIMM that was failing to unlock it was found that the kernel is reporting 'locked' while the DIMM security interface is 'frozen'. Unfortunately the security state is tracked internally as an enum which prevents it from communicating the difference between 'locked' and 'locked + frozen'. It follows that the enum also prevents the kernel from communicating 'unlocked + frozen' which would be useful for debugging why security operations like 'change passphrase' are disabled. Ditch the security state enum for a set of flags and introduce a new sysfs attribute explicitly for the 'frozen' state. The regression risk is low because the 'frozen' state was already blocked behind the 'locked' state, but will need to revisit if there were cases where applications need 'frozen' to show up in the primary 'security' attribute. The expectation is that communicating 'frozen' is mostly a helper for debug and status monitoring. Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reported-by: Jeff Moyer <jmoyer@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Link: https://lore.kernel.org/r/156686729474.184120.5835135644278860826.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* Revert "Merge tag 'keys-acl-20190703' of ↵Linus Torvalds2019-07-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs" This reverts merge 0f75ef6a9cff49ff612f7ce0578bced9d0b38325 (and thus effectively commits 7a1ade847596 ("keys: Provide KEYCTL_GRANT_PERMISSION") 2e12256b9a76 ("keys: Replace uid/gid/perm permissions checking with an ACL") that the merge brought in). It turns out that it breaks booting with an encrypted volume, and Eric biggers reports that it also breaks the fscrypt tests [1] and loading of in-kernel X.509 certificates [2]. The root cause of all the breakage is likely the same, but David Howells is off email so rather than try to work it out it's getting reverted in order to not impact the rest of the merge window. [1] https://lore.kernel.org/lkml/20190710011559.GA7973@sol.localdomain/ [2] https://lore.kernel.org/lkml/20190710013225.GB7973@sol.localdomain/ Link: https://lore.kernel.org/lkml/CAHk-=wjxoeMJfeBahnWH=9zShKp2bsVy527vo3_y8HfOdhwAAw@mail.gmail.com/ Reported-by: Eric Biggers <ebiggers@kernel.org> Cc: David Howells <dhowells@redhat.com> Cc: James Morris <jmorris@namei.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* keys: Replace uid/gid/perm permissions checking with an ACLDavid Howells2019-06-281-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace the uid/gid/perm permissions checking on a key with an ACL to allow the SETATTR and SEARCH permissions to be split. This will also allow a greater range of subjects to represented. ============ WHY DO THIS? ============ The problem is that SETATTR and SEARCH cover a slew of actions, not all of which should be grouped together. For SETATTR, this includes actions that are about controlling access to a key: (1) Changing a key's ownership. (2) Changing a key's security information. (3) Setting a keyring's restriction. And actions that are about managing a key's lifetime: (4) Setting an expiry time. (5) Revoking a key. and (proposed) managing a key as part of a cache: (6) Invalidating a key. Managing a key's lifetime doesn't really have anything to do with controlling access to that key. Expiry time is awkward since it's more about the lifetime of the content and so, in some ways goes better with WRITE permission. It can, however, be set unconditionally by a process with an appropriate authorisation token for instantiating a key, and can also be set by the key type driver when a key is instantiated, so lumping it with the access-controlling actions is probably okay. As for SEARCH permission, that currently covers: (1) Finding keys in a keyring tree during a search. (2) Permitting keyrings to be joined. (3) Invalidation. But these don't really belong together either, since these actions really need to be controlled separately. Finally, there are number of special cases to do with granting the administrator special rights to invalidate or clear keys that I would like to handle with the ACL rather than key flags and special checks. =============== WHAT IS CHANGED =============== The SETATTR permission is split to create two new permissions: (1) SET_SECURITY - which allows the key's owner, group and ACL to be changed and a restriction to be placed on a keyring. (2) REVOKE - which allows a key to be revoked. The SEARCH permission is split to create: (1) SEARCH - which allows a keyring to be search and a key to be found. (2) JOIN - which allows a keyring to be joined as a session keyring. (3) INVAL - which allows a key to be invalidated. The WRITE permission is also split to create: (1) WRITE - which allows a key's content to be altered and links to be added, removed and replaced in a keyring. (2) CLEAR - which allows a keyring to be cleared completely. This is split out to make it possible to give just this to an administrator. (3) REVOKE - see above. Keys acquire ACLs which consist of a series of ACEs, and all that apply are unioned together. An ACE specifies a subject, such as: (*) Possessor - permitted to anyone who 'possesses' a key (*) Owner - permitted to the key owner (*) Group - permitted to the key group (*) Everyone - permitted to everyone Note that 'Other' has been replaced with 'Everyone' on the assumption that you wouldn't grant a permit to 'Other' that you wouldn't also grant to everyone else. Further subjects may be made available by later patches. The ACE also specifies a permissions mask. The set of permissions is now: VIEW Can view the key metadata READ Can read the key content WRITE Can update/modify the key content SEARCH Can find the key by searching/requesting LINK Can make a link to the key SET_SECURITY Can change owner, ACL, expiry INVAL Can invalidate REVOKE Can revoke JOIN Can join this keyring CLEAR Can clear this keyring The KEYCTL_SETPERM function is then deprecated. The KEYCTL_SET_TIMEOUT function then is permitted if SET_SECURITY is set, or if the caller has a valid instantiation auth token. The KEYCTL_INVALIDATE function then requires INVAL. The KEYCTL_REVOKE function then requires REVOKE. The KEYCTL_JOIN_SESSION_KEYRING function then requires JOIN to join an existing keyring. The JOIN permission is enabled by default for session keyrings and manually created keyrings only. ====================== BACKWARD COMPATIBILITY ====================== To maintain backward compatibility, KEYCTL_SETPERM will translate the permissions mask it is given into a new ACL for a key - unless KEYCTL_SET_ACL has been called on that key, in which case an error will be returned. It will convert possessor, owner, group and other permissions into separate ACEs, if each portion of the mask is non-zero. SETATTR permission turns on all of INVAL, REVOKE and SET_SECURITY. WRITE permission turns on WRITE, REVOKE and, if a keyring, CLEAR. JOIN is turned on if a keyring is being altered. The KEYCTL_DESCRIBE function translates the ACL back into a permissions mask to return depending on possessor, owner, group and everyone ACEs. It will make the following mappings: (1) INVAL, JOIN -> SEARCH (2) SET_SECURITY -> SETATTR (3) REVOKE -> WRITE if SETATTR isn't already set (4) CLEAR -> WRITE Note that the value subsequently returned by KEYCTL_DESCRIBE may not match the value set with KEYCTL_SETATTR. ======= TESTING ======= This passes the keyutils testsuite for all but a couple of tests: (1) tests/keyctl/dh_compute/badargs: The first wrong-key-type test now returns EOPNOTSUPP rather than ENOKEY as READ permission isn't removed if the type doesn't have ->read(). You still can't actually read the key. (2) tests/keyctl/permitting/valid: The view-other-permissions test doesn't work as Other has been replaced with Everyone in the ACL. Signed-off-by: David Howells <dhowells@redhat.com>
* libnvdimm/security, acpi/nfit: unify zero-key for all security commandsDave Jiang2019-03-301-48/+69
| | | | | | | | | | | With zero-key defined, we can remove previous detection of key id 0 or null key in order to deal with a zero-key situation. Syncing all security commands to use the zero-key. Helper functions are introduced to return the data that points to the actual key payload or the zero_key. This helps uniformly handle the key material even with zero_key. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* libnvdimm/security: provide fix for secure-erase to use zero-keyDave Jiang2019-03-301-5/+12
| | | | | | | | | | | | | Add a zero key in order to standardize hardware that want a key of 0's to be passed. Some platforms defaults to a zero-key with security enabled rather than allow the OS to enable the security. The zero key would allow us to manage those platform as well. This also adds a fix to secure erase so it can use the zero key to do crypto erase. Some other security commands already use zero keys. This introduces a standard zero-key to allow unification of semantics cross nvdimm security commands. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* libnvdimm/security: Quiet security operationsDan Williams2018-12-221-15/+15
| | | | | | | | | | | | | | | | The security implementation is too chatty. For example, the common case is that security is not enabled / setup, and booting a qemu configuration currently yields: nvdimm nmem0: request_key() found no key nvdimm nmem0: failed to unlock dimm: -126 nvdimm nmem1: request_key() found no key nvdimm nmem1: failed to unlock dimm: -126 Convert all security related log messages to debug level. Cc: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* acpi/nfit, libnvdimm/security: add Intel DSM 1.8 master passphrase supportDave Jiang2018-12-211-12/+31
| | | | | | | | | | | | | | With Intel DSM 1.8 [1] two new security DSMs are introduced. Enable/update master passphrase and master secure erase. The master passphrase allows a secure erase to be performed without the user passphrase that is set on the NVDIMM. The commands of master_update and master_erase are added to the sysfs knob in order to initiate the DSMs. They are similar in opeartion mechanism compare to update and erase. [1]: http://pmem.io/documents/NVDIMM_DSM_Interface-V1.8.pdf Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* acpi/nfit, libnvdimm/security: Add security DSM overwrite supportDave Jiang2018-12-211-0/+133
| | | | | | | | | | | | | | | | | | | | Add support for the NVDIMM_FAMILY_INTEL "ovewrite" capability as described by the Intel DSM spec v1.7. This will allow triggering of overwrite on Intel NVDIMMs. The overwrite operation can take tens of minutes. When the overwrite DSM is issued successfully, the NVDIMMs will be unaccessible. The kernel will do backoff polling to detect when the overwrite process is completed. According to the DSM spec v1.7, the 128G NVDIMMs can take up to 15mins to perform overwrite and larger DIMMs will take longer. Given that overwrite puts the DIMM in an indeterminate state until it completes introduce the NDD_SECURITY_OVERWRITE flag to prevent other operations from executing when overwrite is happening. The NDD_WORK_PENDING flag is added to denote that there is a device reference on the nvdimm device for an async workqueue thread context. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* acpi/nfit, libnvdimm: Add support for issue secure erase DSM to Intel nvdimmDave Jiang2018-12-211-0/+41
| | | | | | | | | | Add support to issue a secure erase DSM to the Intel nvdimm. The required passphrase is acquired from an encrypted key in the kernel user keyring. To trigger the action, "erase <keyid>" is written to the "security" sysfs attribute. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* acpi/nfit, libnvdimm: Add enable/update passphrase support for Intel nvdimmsDave Jiang2018-12-211-4/+54
| | | | | | | | | | | Add support for enabling and updating passphrase on the Intel nvdimms. The passphrase is the an encrypted key in the kernel user keyring. We trigger the update via writing "update <old_keyid> <new_keyid>" to the sysfs attribute "security". If no <old_keyid> exists (for enabling security) then a 0 should be used. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* acpi/nfit, libnvdimm: Add disable passphrase support to Intel nvdimm.Dave Jiang2018-12-211-0/+63
| | | | | | | | | | Add support to disable passphrase (security) for the Intel nvdimm. The passphrase used for disabling is pulled from an encrypted-key in the kernel user keyring. The action is triggered by writing "disable <keyid>" to the sysfs attribute "security". Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* acpi/nfit, libnvdimm: Add unlock of nvdimm support for Intel DIMMsDave Jiang2018-12-141-0/+148
Add support to unlock the dimm via the kernel key management APIs. The passphrase is expected to be pulled from userspace through keyutils. The key management and sysfs attributes are libnvdimm generic. Encrypted keys are used to protect the nvdimm passphrase at rest. The master key can be a trusted-key sealed in a TPM, preferred, or an encrypted-key, more flexible, but more exposure to a potential attacker. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Co-developed-by: Dan Williams <dan.j.williams@intel.com> Reported-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>