Few storage technologies such is EMMC, UFS, and NVMe support RPMB hardware partition with common protocol and frame layout. The RPMB partition cannot be accessed via standard block layer, but by a set of specific commands: WRITE, READ, GET_WRITE_COUNTER, and PROGRAM_KEY. Such a partition provides authenticated and replay protected access, hence suitable as a secure storage. The RPMB layer aims to provide in-kernel API for Trusted Execution Environment (TEE) devices that are capable to securely compute block frame signature. In case a TEE device wish to store a replay protected data, it creates an RPMB frame with requested data and computes HMAC of the frame, then it requests the storage device via RPMB layer to store the data. A TEE driver can claim the RPMB interface, for example, via class_interface_register (). The layer provides two APIs, for rpmb_req_cmd() for issuing one of RPMB specific commands and rpmb_seq_cmd() for issuing of raw RPMB protocol frames, which is close to emmc multi ioctl interface. A storage device registers its RPMB hardware (eMMC) partition or RPMB W-LUN (UFS) with the RPMB layer providing an implementation for rpmb_seq_cmd() handler. The interface enables sending sequence of RPMB standard frames. A parallel user space API is provided via /dev/rpmbX character device with two IOCTL commands. Simplified one, RPMB_IOC_REQ_CMD, were read result cycles is performed by the framework on behalf the user and second, RPMB_IOC_SEQ_CMD where the whole RPMB sequence, including RESULT_READ is supplied by the caller. The latter is intended for easier adjusting of the applications that use MMC_IOC_MULTI_CMD ioctl, such as https://android.googlesource.com/trusty/app/storage/ There is a also sample tool under tools/rpmb/ directory that exercises these interfaces and a simulation device that implements the device part. Tomas Winkler (8): rpmb: add Replay Protected Memory Block (RPMB) subsystem char: rpmb: add sysfs-class ABI documentation char: rpmb: add device attributes char: rpmb: provide a user space interface char: rpmb: add RPMB simulation device tools rpmb: add RPBM access tool mmc: block: register RPMB partition with the RPMB subsystem scsi: ufs: connect to RPMB subsystem Documentation/ABI/testing/sysfs-class-rpmb | 44 ++ Documentation/ioctl/ioctl-number.txt | 1 + MAINTAINERS | 10 + drivers/char/Kconfig | 2 + drivers/char/Makefile | 1 + drivers/char/rpmb/Kconfig | 25 + drivers/char/rpmb/Makefile | 6 + drivers/char/rpmb/cdev.c | 269 ++++++++ drivers/char/rpmb/core.c | 484 +++++++++++++++ drivers/char/rpmb/rpmb-cdev.h | 25 + drivers/char/rpmb/rpmb_sim.c | 668 ++++++++++++++++++++ drivers/mmc/card/Kconfig | 1 + drivers/mmc/card/block.c | 258 +++++++- drivers/scsi/ufs/Kconfig | 1 + drivers/scsi/ufs/ufshcd.c | 183 ++++++ drivers/scsi/ufs/ufshcd.h | 2 + include/linux/rpmb.h | 165 +++++ include/uapi/linux/Kbuild | 1 + include/uapi/linux/rpmb.h | 152 +++++ tools/Makefile | 14 +- tools/rpmb/.gitignore | 2 + tools/rpmb/Makefile | 33 + tools/rpmb/rpmb.c | 948 +++++++++++++++++++++++++++++ 23 files changed, 3287 insertions(+), 8 deletions(-) create mode 100644 Documentation/ABI/testing/sysfs-class-rpmb create mode 100644 drivers/char/rpmb/Kconfig create mode 100644 drivers/char/rpmb/Makefile create mode 100644 drivers/char/rpmb/cdev.c create mode 100644 drivers/char/rpmb/core.c create mode 100644 drivers/char/rpmb/rpmb-cdev.h create mode 100644 drivers/char/rpmb/rpmb_sim.c create mode 100644 include/linux/rpmb.h create mode 100644 include/uapi/linux/rpmb.h create mode 100644 tools/rpmb/.gitignore create mode 100644 tools/rpmb/Makefile create mode 100644 tools/rpmb/rpmb.c -- 2.5.5 -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
