torvalds/linux

What:        /sys/kernel/config/tsm/report/$name/inblob
Date:        September, 2023
KernelVersion:    v6.7
Contact:    linux-coco@lists.linux.dev
Description:
        (WO) Up to 64 bytes of user specified binary data. For replay
        protection this should include a nonce, but the kernel does not
        place any restrictions on the content.

What:        /sys/kernel/config/tsm/report/$name/outblob
Date:        September, 2023
KernelVersion:    v6.7
Contact:    linux-coco@lists.linux.dev
Description:
        (RO) Binary attestation report generated from @inblob and other
        options The format of the report is implementation specific
        where the implementation is conveyed via the @provider
        attribute.

What:        /sys/kernel/config/tsm/report/$name/auxblob
Date:        October, 2023
KernelVersion:    v6.7
Contact:    linux-coco@lists.linux.dev
Description:
        (RO) Optional supplemental data that a TSM may emit, visibility
        of this attribute depends on TSM, and may be empty if no
        auxiliary data is available.

        When @provider is "sev_guest" this file contains the
        "cert_table" from SEV-ES Guest-Hypervisor Communication Block
        Standardization v2.03 Section 4.1.8.1 MSG_REPORT_REQ.
        https://www.amd.com/content/dam/amd/en/documents/epyc-technical-docs/specifications/56421.pdf

What:        /sys/kernel/config/tsm/report/$name/provider
Date:        September, 2023
KernelVersion:    v6.7
Contact:    linux-coco@lists.linux.dev
Description:
        (RO) A name for the format-specification of @outblob like
        "sev_guest" [1] or "tdx_guest" [2] in the near term, or a
        common standard format in the future.

        [1]: SEV Secure Nested Paging Firmware ABI Specification
        Revision 1.55 Table 22
        https://www.amd.com/content/dam/amd/en/documents/epyc-technical-docs/specifications/56860.pdf

        [2]: Intel® Trust Domain Extensions Data Center Attestation
        Primitives : Quote Generation Library and Quote Verification
        Library Revision 0.8 Appendix 4,5
        https://download.01.org/intel-sgx/latest/dcap-latest/linux/docs/Intel_TDX_DCAP_Quoting_Library_API.pdf

What:        /sys/kernel/config/tsm/report/$name/generation
Date:        September, 2023
KernelVersion:    v6.7
Contact:    linux-coco@lists.linux.dev
Description:
        (RO) The value in this attribute increments each time @inblob or
        any option is written. Userspace can detect conflicts by
        checking generation before writing to any attribute and making
        sure the number of writes matches expectations after reading
        @outblob, or it can prevent conflicts by creating a report
        instance per requesting context.

What:        /sys/kernel/config/tsm/report/$name/privlevel
Date:        September, 2023
KernelVersion:    v6.7
Contact:    linux-coco@lists.linux.dev
Description:
        (WO) Attribute is visible if a TSM implementation provider
        supports the concept of attestation reports for TVMs running at
        different privilege levels, like SEV-SNP "VMPL", specify the
        privilege level via this attribute.  The minimum acceptable
        value is conveyed via @privlevel_floor and the maximum
        acceptable value is TSM_PRIVLEVEL_MAX (3).

What:        /sys/kernel/config/tsm/report/$name/privlevel_floor
Date:        September, 2023
KernelVersion:    v6.7
Contact:    linux-coco@lists.linux.dev
Description:
        (RO) Indicates the minimum permissible value that can be written
        to @privlevel.