[RFC 00/12] Multi-Key Total Memory Encryption API (MKTME)

[Huang, Kai]

> -----Original Message-----
> From: keyrings-owner at vger.kernel.org [mailto:keyrings-
> owner at vger.kernel.org] On Behalf Of Alison Schofield
> Sent: Saturday, September 8, 2018 10:23 AM
> To: dhowells at redhat.com; tglx at linutronix.de
> Cc: Huang, Kai <kai.huang at intel.com>; Nakajima, Jun
> <jun.nakajima at intel.com>; Shutemov, Kirill <kirill.shutemov at intel.com>;
> Hansen, Dave <dave.hansen at intel.com>; Sakkinen, Jarkko
> <jarkko.sakkinen at intel.com>; jmorris at namei.org; keyrings at vger.kernel.org;
> linux-security-module at vger.kernel.org; mingo at redhat.com; hpa at zytor.com;
> x86 at kernel.org; linux-mm at kvack.org
> Subject: [RFC 00/12] Multi-Key Total Memory Encryption API (MKTME)
> 
> Seeking comments on the APIs supporting MKTME on future Intel platforms.
> 
> MKTME (Multi-Key Total Memory Encryption) is a technology supporting
> memory encryption on upcoming Intel platforms. Whereas TME allows
> encryption of the entire system memory using a single key, MKTME allows
> mulitple encryption domains, each having their own key. While the main use
> case for the feature is virtual machine isolation, the API needs the flexibility to
> work for a wide range of use cases.
> 
> This RFC presents the 2 API additions that enable userspace to:
>  1) Create Encryption Keys: Kernel Key Service type "mktme"
>  2) Use the Encryption Keys: system call encrypt_mprotect()
> 
> In order to share between: the Kernel Key Service, the new system call, and the
> existing mm code, helper functions were created in arch/x86/mktme

IMHO, we can separate this series into 2 parts, as you did above, and send out them separately. The reason is, in general I think adding new MKTME type to key retention services is not that related to memory management code, namely the encrypt_mprotect() API part.

So if we split the two parts and send them out separately, the first part can be reviewed by keyring and security guys, without involving mm guys, and the encrypt_mprotect() part can be more reviewed more by mm guys. 

And since encrypt_mprotect() is a new syscall, you may need to add more lists for the review, ie, linux-api, and maybe linux-kernel as well.

Thanks,
-Kai

> 
> This patchset is built upon Kirill Shutemov's patchset for the core MKTME
> support. You can find that here:
> git://git.kernel.org/pub/scm/linux/kernel/git/kas/linux.git mktme/wip
> 
> 
> Alison Schofield (12):
>   docs/x86: Document the Multi-Key Total Memory Encryption API
>   mm: Generalize the mprotect implementation to support extensions
>   syscall/x86: Wire up a new system call for memory encryption keys
>   x86/mm: Add helper functions to manage memory encryption keys
>   x86/mm: Add a helper function to set keyid bits in encrypted VMA's
>   mm: Add the encrypt_mprotect() system call
>   x86/mm: Add helper functions to track encrypted VMA's
>   mm: Track VMA's in use for each memory encryption keyid
>   mm: Restrict memory encryption to anonymous VMA's
>   x86/pconfig: Program memory encryption keys on a system-wide basis
>   keys/mktme: Add a new key service type for memory encryption keys
>   keys/mktme: Do not revoke in use memory encryption keys
> 
>  Documentation/x86/mktme-keys.txt       | 153 ++++++++++++++++
>  arch/x86/Kconfig                       |   1 +
>  arch/x86/entry/syscalls/syscall_32.tbl |   1 +
>  arch/x86/entry/syscalls/syscall_64.tbl |   1 +
>  arch/x86/include/asm/intel_pconfig.h   |  42 ++++-
>  arch/x86/include/asm/mktme.h           |  21 +++
>  arch/x86/mm/mktme.c                    | 141 ++++++++++++++
>  fs/exec.c                              |   4 +-
>  include/keys/mktme-type.h              |  28 +++
>  include/linux/key.h                    |   2 +
>  include/linux/mm.h                     |   9 +-
>  include/linux/syscalls.h               |   2 +
>  include/uapi/asm-generic/unistd.h      |   4 +-
>  kernel/fork.c                          |   2 +
>  kernel/sys_ni.c                        |   2 +
>  mm/mmap.c                              |  12 ++
>  mm/mprotect.c                          |  93 +++++++++-
>  mm/nommu.c                             |   4 +
>  security/keys/Kconfig                  |  11 ++
>  security/keys/Makefile                 |   1 +
>  security/keys/internal.h               |   6 +
>  security/keys/keyctl.c                 |   7 +
>  security/keys/mktme_keys.c             | 325
> +++++++++++++++++++++++++++++++++
>  23 files changed, 855 insertions(+), 17 deletions(-)  create mode 100644
> Documentation/x86/mktme-keys.txt  create mode 100644 include/keys/mktme-
> type.h  create mode 100644 security/keys/mktme_keys.c
> 
> --
> 2.14.1