Commit 104edb94 authored by Sumit Garg's avatar Sumit Garg Committed by Jens Wiklander
Browse files

tee: add private login method for kernel clients 



There are use-cases where user-space shouldn't be allowed to communicate
directly with a TEE device which is dedicated to provide a specific
service for a kernel client. So add a private login method for kernel
clients and disallow user-space to open-session using GP implementation
defined login method range: (0x80000000 - 0xBFFFFFFF).

Reviewed-by: default avatarJerome Forissier <jerome@forissier.org>
Signed-off-by: default avatarSumit Garg <sumit.garg@linaro.org>
Signed-off-by: default avatarJens Wiklander <jens.wiklander@linaro.org>
parent 2a6ba3f7

drivers/tee/tee_core.c

+7 −0
Original line number Diff line number Diff line
@@ -333,6 +333,13 @@ static int tee_ioctl_open_session(struct tee_context *ctx, 
			goto out;

	}



	if (arg.clnt_login >= TEE_IOCTL_LOGIN_REE_KERNEL_MIN &&

	    arg.clnt_login <= TEE_IOCTL_LOGIN_REE_KERNEL_MAX) {

		pr_debug("login method not allowed for user-space client\n");

		rc = -EPERM;

		goto out;

	}



	rc = ctx->teedev->desc->ops->open_session(ctx, &arg, params);

	if (rc)

		goto out;

include/uapi/linux/tee.h

+9 −0
Original line number Diff line number Diff line
@@ -173,6 +173,15 @@ struct tee_ioctl_buf_data { 
#define TEE_IOCTL_LOGIN_APPLICATION		4

#define TEE_IOCTL_LOGIN_USER_APPLICATION	5

#define TEE_IOCTL_LOGIN_GROUP_APPLICATION	6

/*

 * Disallow user-space to use GP implementation specific login

 * method range (0x80000000 - 0xBFFFFFFF). This range is rather

 * being reserved for REE kernel clients or TEE implementation.

 */

#define TEE_IOCTL_LOGIN_REE_KERNEL_MIN		0x80000000

#define TEE_IOCTL_LOGIN_REE_KERNEL_MAX		0xBFFFFFFF

/* Private login method for REE kernel clients */

#define TEE_IOCTL_LOGIN_REE_KERNEL		0x80000000



/**

 * struct tee_ioctl_param - parameter