Add support for TEE based trusted keys where TEE provides the functionality to seal and unseal trusted keys using hardware unique key. Also, this is an alternative in case platform doesn't possess a TPM device.
This series also adds some TEE features like:
Patch #1, #2 enables support for registered kernel shared memory with TEE.
Patch #3 enables support for private kernel login method required for cases like trusted keys where we don't wan't user-space to directly access TEE service to retrieve trusted key contents.
Rest of the patches from #4 to #7 adds support for TEE based trusted keys.
This patch-set has been tested with OP-TEE based pseudo TA which can be found here [1].
Looking forward to your valuable feedback/suggestions.
[1] https://github.com/OP-TEE/optee_os/pull/3082
Sumit Garg (7): tee: optee: allow kernel pages to register as shm tee: enable support to register kernel memory tee: add private login method for kernel clients KEYS: trusted: Introduce TEE based Trusted Keys KEYS: encrypted: Allow TEE based trusted master keys doc: keys: Document usage of TEE based Trusted Keys MAINTAINERS: Add entry for TEE based Trusted Keys
Documentation/security/keys/tee-trusted.rst | 93 +++++ MAINTAINERS | 9 + drivers/tee/optee/call.c | 7 + drivers/tee/tee_core.c | 6 + drivers/tee/tee_shm.c | 16 +- include/keys/tee_trusted.h | 84 ++++ include/keys/trusted-type.h | 1 + include/linux/tee_drv.h | 1 + include/uapi/linux/tee.h | 2 + security/keys/Kconfig | 3 + security/keys/Makefile | 3 + security/keys/encrypted-keys/masterkey_trusted.c | 10 +- security/keys/tee_trusted.c | 506 +++++++++++++++++++++++ 13 files changed, 737 insertions(+), 4 deletions(-) create mode 100644 Documentation/security/keys/tee-trusted.rst create mode 100644 include/keys/tee_trusted.h create mode 100644 security/keys/tee_trusted.c
Kernel pages are marked as normal type memory only so allow kernel pages to be registered as shared memory with OP-TEE.
Signed-off-by: Sumit Garg sumit.garg@linaro.org --- drivers/tee/optee/call.c | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/drivers/tee/optee/call.c b/drivers/tee/optee/call.c index aa94270..bce45b1 100644 --- a/drivers/tee/optee/call.c +++ b/drivers/tee/optee/call.c @@ -553,6 +553,13 @@ static int check_mem_type(unsigned long start, size_t num_pages) struct mm_struct *mm = current->mm; int rc;
+ /* + * Allow kernel address to register with OP-TEE as kernel + * pages are configured as normal memory only. + */ + if (virt_addr_valid(start)) + return 0; + down_read(&mm->mmap_sem); rc = __check_mem_type(find_vma(mm, start), start + num_pages * PAGE_SIZE);
On Thu, Jun 13, 2019 at 04:00:27PM +0530, Sumit Garg wrote:
Kernel pages are marked as normal type memory only so allow kernel pages to be registered as shared memory with OP-TEE.
Signed-off-by: Sumit Garg sumit.garg@linaro.org
Just out of pure interest why this was not allowed before?
/Jarkko
On Thu, Jun 13, 2019 at 06:12:57PM +0300, Jarkko Sakkinen wrote:
On Thu, Jun 13, 2019 at 04:00:27PM +0530, Sumit Garg wrote:
Kernel pages are marked as normal type memory only so allow kernel pages to be registered as shared memory with OP-TEE.
Signed-off-by: Sumit Garg sumit.garg@linaro.org
Just out of pure interest why this was not allowed before?
Please spare me and ignore that one :-) Obviouslly because it was not used.
Acked-by: Jarkko Sakkinen jarkko.sakkinen@linux.intel.com
/Jarkko
On Thu, Jun 13, 2019 at 06:17:14PM +0300, Jarkko Sakkinen wrote:
On Thu, Jun 13, 2019 at 06:12:57PM +0300, Jarkko Sakkinen wrote:
On Thu, Jun 13, 2019 at 04:00:27PM +0530, Sumit Garg wrote:
Kernel pages are marked as normal type memory only so allow kernel pages to be registered as shared memory with OP-TEE.
Signed-off-by: Sumit Garg sumit.garg@linaro.org
Just out of pure interest why this was not allowed before?
Please spare me and ignore that one :-) Obviouslly because it was not used.
Acked-by: Jarkko Sakkinen jarkko.sakkinen@linux.intel.com
Actually,
Reviewed-by: Jarkko Sakkinen jarkko.sakkinen@linux.intel.com
/Jarkko
On Thu, 13 Jun 2019 at 20:47, Jarkko Sakkinen jarkko.sakkinen@linux.intel.com wrote:
On Thu, Jun 13, 2019 at 06:17:14PM +0300, Jarkko Sakkinen wrote:
On Thu, Jun 13, 2019 at 06:12:57PM +0300, Jarkko Sakkinen wrote:
On Thu, Jun 13, 2019 at 04:00:27PM +0530, Sumit Garg wrote:
Kernel pages are marked as normal type memory only so allow kernel pages to be registered as shared memory with OP-TEE.
Signed-off-by: Sumit Garg sumit.garg@linaro.org
Just out of pure interest why this was not allowed before?
Please spare me and ignore that one :-) Obviouslly because it was not used.
Acked-by: Jarkko Sakkinen jarkko.sakkinen@linux.intel.com
Actually,
Reviewed-by: Jarkko Sakkinen jarkko.sakkinen@linux.intel.com
Thanks.
-Sumit
/Jarkko
On Thu, Jun 13, 2019 at 04:00:27PM +0530, Sumit Garg wrote:
Kernel pages are marked as normal type memory only so allow kernel pages to be registered as shared memory with OP-TEE.
Signed-off-by: Sumit Garg sumit.garg@linaro.org
Reviewed-by: Jens Wiklander jens.wiklander@linaro.org
Thanks, Jens
Enable support to register kernel memory reference with TEE. This change will allow TEE bus drivers to register memory references.
Signed-off-by: Sumit Garg sumit.garg@linaro.org --- drivers/tee/tee_shm.c | 16 ++++++++++++++-- include/linux/tee_drv.h | 1 + 2 files changed, 15 insertions(+), 2 deletions(-)
diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c index 2da026f..5c69b89 100644 --- a/drivers/tee/tee_shm.c +++ b/drivers/tee/tee_shm.c @@ -9,6 +9,7 @@ #include <linux/sched.h> #include <linux/slab.h> #include <linux/tee_drv.h> +#include <linux/uio.h> #include "tee_private.h"
static void tee_shm_release(struct tee_shm *shm) @@ -224,13 +225,14 @@ struct tee_shm *tee_shm_register(struct tee_context *ctx, unsigned long addr, { struct tee_device *teedev = ctx->teedev; const u32 req_flags = TEE_SHM_DMA_BUF | TEE_SHM_USER_MAPPED; + const u32 req_ker_flags = TEE_SHM_DMA_BUF | TEE_SHM_KERNEL_MAPPED; struct tee_shm *shm; void *ret; int rc; int num_pages; unsigned long start;
- if (flags != req_flags) + if (flags != req_flags && flags != req_ker_flags) return ERR_PTR(-ENOTSUPP);
if (!tee_device_get(teedev)) @@ -264,7 +266,17 @@ struct tee_shm *tee_shm_register(struct tee_context *ctx, unsigned long addr, goto err; }
- rc = get_user_pages_fast(start, num_pages, FOLL_WRITE, shm->pages); + if (flags & TEE_SHM_USER_MAPPED) { + rc = get_user_pages_fast(start, num_pages, FOLL_WRITE, + shm->pages); + } else { + const struct kvec kiov = { + .iov_base = (void *)start, + .iov_len = PAGE_SIZE + }; + + rc = get_kernel_pages(&kiov, num_pages, 0, shm->pages); + } if (rc > 0) shm->num_pages = rc; if (rc != num_pages) { diff --git a/include/linux/tee_drv.h b/include/linux/tee_drv.h index 7a03f68..dedf8fa 100644 --- a/include/linux/tee_drv.h +++ b/include/linux/tee_drv.h @@ -26,6 +26,7 @@ #define TEE_SHM_REGISTER BIT(3) /* Memory registered in secure world */ #define TEE_SHM_USER_MAPPED BIT(4) /* Memory mapped in user space */ #define TEE_SHM_POOL BIT(5) /* Memory allocated from pool */ +#define TEE_SHM_KERNEL_MAPPED BIT(6) /* Memory mapped in kernel space */
struct device; struct tee_device;
On Thu, Jun 13, 2019 at 04:00:28PM +0530, Sumit Garg wrote:
Enable support to register kernel memory reference with TEE. This change will allow TEE bus drivers to register memory references.
Signed-off-by: Sumit Garg sumit.garg@linaro.org
Reviewed-by: Jarkko Sakkinen jarkko.sakkinen@linux.intel.com
/Jarkko
On Thu, 13 Jun 2019 at 20:50, Jarkko Sakkinen jarkko.sakkinen@linux.intel.com wrote:
On Thu, Jun 13, 2019 at 04:00:28PM +0530, Sumit Garg wrote:
Enable support to register kernel memory reference with TEE. This change will allow TEE bus drivers to register memory references.
Signed-off-by: Sumit Garg sumit.garg@linaro.org
Reviewed-by: Jarkko Sakkinen jarkko.sakkinen@linux.intel.com
Thanks.
-Sumit
/Jarkko
On Thu, Jun 13, 2019 at 04:00:28PM +0530, Sumit Garg wrote:
Enable support to register kernel memory reference with TEE. This change will allow TEE bus drivers to register memory references.
Signed-off-by: Sumit Garg sumit.garg@linaro.org
Reviewed-by: Jens Wiklander jens.wiklander@linaro.org
Thanks, Jens
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 this login method.
Signed-off-by: Sumit Garg sumit.garg@linaro.org --- drivers/tee/tee_core.c | 6 ++++++ include/uapi/linux/tee.h | 2 ++ 2 files changed, 8 insertions(+)
diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c index 0f16d9f..4581bd1 100644 --- a/drivers/tee/tee_core.c +++ b/drivers/tee/tee_core.c @@ -334,6 +334,12 @@ static int tee_ioctl_open_session(struct tee_context *ctx, goto out; }
+ if (arg.clnt_login == TEE_IOCTL_LOGIN_REE_KERNEL) { + pr_err("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; diff --git a/include/uapi/linux/tee.h b/include/uapi/linux/tee.h index 4b9eb06..f33c69c 100644 --- a/include/uapi/linux/tee.h +++ b/include/uapi/linux/tee.h @@ -172,6 +172,8 @@ 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 +/* Private login method for REE kernel clients */ +#define TEE_IOCTL_LOGIN_REE_KERNEL 0x80000000
/** * struct tee_ioctl_param - parameter
Hi Sumit,
On Thu, Jun 13, 2019 at 04:00:29PM +0530, Sumit Garg wrote:
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 this login method.
Signed-off-by: Sumit Garg sumit.garg@linaro.org
drivers/tee/tee_core.c | 6 ++++++ include/uapi/linux/tee.h | 2 ++ 2 files changed, 8 insertions(+)
diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c index 0f16d9f..4581bd1 100644 --- a/drivers/tee/tee_core.c +++ b/drivers/tee/tee_core.c @@ -334,6 +334,12 @@ static int tee_ioctl_open_session(struct tee_context *ctx, goto out; }
- if (arg.clnt_login == TEE_IOCTL_LOGIN_REE_KERNEL) {
TEE_IOCTL_LOGIN_REE_KERNEL is defined as 0x80000000 which is in the range specified and implementation defined by the GP spec. I wonder if we shouldn't filter the entire implementation defined range instead of just this value.
pr_err("login method not allowed for user-space client\n");
pr_debug(), if it's needed at all.
rc = -EPERM;
goto out;
- }
- rc = ctx->teedev->desc->ops->open_session(ctx, &arg, params); if (rc) goto out;
diff --git a/include/uapi/linux/tee.h b/include/uapi/linux/tee.h index 4b9eb06..f33c69c 100644 --- a/include/uapi/linux/tee.h +++ b/include/uapi/linux/tee.h @@ -172,6 +172,8 @@ 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 +/* Private login method for REE kernel clients */
It's worth noting that this is filtered by the TEE framework, compared to everything else which is treated opaquely.
+#define TEE_IOCTL_LOGIN_REE_KERNEL 0x80000000 /**
- struct tee_ioctl_param - parameter
-- 2.7.4
Thanks, Jens
Thanks Jens for your comments.
On Mon, 8 Jul 2019 at 21:09, Jens Wiklander jens.wiklander@linaro.org wrote:
Hi Sumit,
On Thu, Jun 13, 2019 at 04:00:29PM +0530, Sumit Garg wrote:
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 this login method.
Signed-off-by: Sumit Garg sumit.garg@linaro.org
drivers/tee/tee_core.c | 6 ++++++ include/uapi/linux/tee.h | 2 ++ 2 files changed, 8 insertions(+)
diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c index 0f16d9f..4581bd1 100644 --- a/drivers/tee/tee_core.c +++ b/drivers/tee/tee_core.c @@ -334,6 +334,12 @@ static int tee_ioctl_open_session(struct tee_context *ctx, goto out; }
if (arg.clnt_login == TEE_IOCTL_LOGIN_REE_KERNEL) {
TEE_IOCTL_LOGIN_REE_KERNEL is defined as 0x80000000 which is in the range specified and implementation defined by the GP spec. I wonder if we shouldn't filter the entire implementation defined range instead of just this value.
Agree. Will rather check for entire implementation defined range: 0x80000000 - 0xFFFFFFFF.
pr_err("login method not allowed for user-space client\n");
pr_debug(), if it's needed at all.
Ok will use pr_debug() instead.
rc = -EPERM;
goto out;
}
rc = ctx->teedev->desc->ops->open_session(ctx, &arg, params); if (rc) goto out;
diff --git a/include/uapi/linux/tee.h b/include/uapi/linux/tee.h index 4b9eb06..f33c69c 100644 --- a/include/uapi/linux/tee.h +++ b/include/uapi/linux/tee.h @@ -172,6 +172,8 @@ 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 +/* Private login method for REE kernel clients */
It's worth noting that this is filtered by the TEE framework, compared to everything else which is treated opaquely.
IIUC, you are referring to login filter in optee_os. Change to prevent filter for this login method is part of this PR [1].
[1] https://github.com/OP-TEE/optee_os/pull/3082
-Sumit
+#define TEE_IOCTL_LOGIN_REE_KERNEL 0x80000000
/**
- struct tee_ioctl_param - parameter
-- 2.7.4
Thanks, Jens
On Tue, Jul 09, 2019 at 11:26:19AM +0530, Sumit Garg wrote:
Thanks Jens for your comments.
On Mon, 8 Jul 2019 at 21:09, Jens Wiklander jens.wiklander@linaro.org wrote:
Hi Sumit,
On Thu, Jun 13, 2019 at 04:00:29PM +0530, Sumit Garg wrote:
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 this login method.
Signed-off-by: Sumit Garg sumit.garg@linaro.org
drivers/tee/tee_core.c | 6 ++++++ include/uapi/linux/tee.h | 2 ++ 2 files changed, 8 insertions(+)
diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c index 0f16d9f..4581bd1 100644 --- a/drivers/tee/tee_core.c +++ b/drivers/tee/tee_core.c @@ -334,6 +334,12 @@ static int tee_ioctl_open_session(struct tee_context *ctx, goto out; }
if (arg.clnt_login == TEE_IOCTL_LOGIN_REE_KERNEL) {
TEE_IOCTL_LOGIN_REE_KERNEL is defined as 0x80000000 which is in the range specified and implementation defined by the GP spec. I wonder if we shouldn't filter the entire implementation defined range instead of just this value.
Agree. Will rather check for entire implementation defined range: 0x80000000 - 0xFFFFFFFF.
pr_err("login method not allowed for user-space client\n");
pr_debug(), if it's needed at all.
Ok will use pr_debug() instead.
rc = -EPERM;
goto out;
}
rc = ctx->teedev->desc->ops->open_session(ctx, &arg, params); if (rc) goto out;
diff --git a/include/uapi/linux/tee.h b/include/uapi/linux/tee.h index 4b9eb06..f33c69c 100644 --- a/include/uapi/linux/tee.h +++ b/include/uapi/linux/tee.h @@ -172,6 +172,8 @@ 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 +/* Private login method for REE kernel clients */
It's worth noting that this is filtered by the TEE framework, compared to everything else which is treated opaquely.
IIUC, you are referring to login filter in optee_os. Change to prevent filter for this login method is part of this PR [1].
No, I was referring to the changes in tee_ioctl_open_session() above. It's relevant for user space to know since it will be prevented from using that range of login identifiers. This will restrict the user space API, but I think the risk of breakage is minimal as OP-TEE is the only in-tree driver registering in the TEE framework. I'm not aware of any out-of-tree drivers registering.
Thanks, Jens
-Sumit
+#define TEE_IOCTL_LOGIN_REE_KERNEL 0x80000000
/**
- struct tee_ioctl_param - parameter
-- 2.7.4
Thanks, Jens
On Tue, 9 Jul 2019 at 12:33, Jens Wiklander jens.wiklander@linaro.org wrote:
On Tue, Jul 09, 2019 at 11:26:19AM +0530, Sumit Garg wrote:
Thanks Jens for your comments.
On Mon, 8 Jul 2019 at 21:09, Jens Wiklander jens.wiklander@linaro.org wrote:
Hi Sumit,
On Thu, Jun 13, 2019 at 04:00:29PM +0530, Sumit Garg wrote:
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 this login method.
Signed-off-by: Sumit Garg sumit.garg@linaro.org
drivers/tee/tee_core.c | 6 ++++++ include/uapi/linux/tee.h | 2 ++ 2 files changed, 8 insertions(+)
diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c index 0f16d9f..4581bd1 100644 --- a/drivers/tee/tee_core.c +++ b/drivers/tee/tee_core.c @@ -334,6 +334,12 @@ static int tee_ioctl_open_session(struct tee_context *ctx, goto out; }
if (arg.clnt_login == TEE_IOCTL_LOGIN_REE_KERNEL) {
TEE_IOCTL_LOGIN_REE_KERNEL is defined as 0x80000000 which is in the range specified and implementation defined by the GP spec. I wonder if we shouldn't filter the entire implementation defined range instead of just this value.
Agree. Will rather check for entire implementation defined range: 0x80000000 - 0xFFFFFFFF.
I had a second thought on this. It would be more restrictive for user-space TEE client library which may need to use implementation defined login method. So either we could define specific ranges for kernel and user-space or we can start with single login method reserved for kernel.
pr_err("login method not allowed for user-space client\n");
pr_debug(), if it's needed at all.
Ok will use pr_debug() instead.
rc = -EPERM;
goto out;
}
rc = ctx->teedev->desc->ops->open_session(ctx, &arg, params); if (rc) goto out;
diff --git a/include/uapi/linux/tee.h b/include/uapi/linux/tee.h index 4b9eb06..f33c69c 100644 --- a/include/uapi/linux/tee.h +++ b/include/uapi/linux/tee.h @@ -172,6 +172,8 @@ 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 +/* Private login method for REE kernel clients */
It's worth noting that this is filtered by the TEE framework, compared to everything else which is treated opaquely.
IIUC, you are referring to login filter in optee_os. Change to prevent filter for this login method is part of this PR [1].
No, I was referring to the changes in tee_ioctl_open_session() above. It's relevant for user space to know since it will be prevented from using that range of login identifiers.
Ok, so you mean to extend the comment here for user-space to know that this login method/range is filtered by the TEE framework. Will do that.
This will restrict the user space API, but I think the risk of breakage is minimal as OP-TEE is the only in-tree driver registering in the TEE framework. I'm not aware of any out-of-tree drivers registering.
I am not sure if I follow you here. How do you expect this change to break out-of-tree TEE driver registration?
-Sumit
Thanks, Jens
-Sumit
+#define TEE_IOCTL_LOGIN_REE_KERNEL 0x80000000
/**
- struct tee_ioctl_param - parameter
-- 2.7.4
Thanks, Jens
Hi Sumit,
On Tue, Jul 9, 2019 at 11:36 AM Sumit Garg sumit.garg@linaro.org wrote:
On Tue, 9 Jul 2019 at 12:33, Jens Wiklander jens.wiklander@linaro.org wrote:
On Tue, Jul 09, 2019 at 11:26:19AM +0530, Sumit Garg wrote:
Thanks Jens for your comments.
On Mon, 8 Jul 2019 at 21:09, Jens Wiklander jens.wiklander@linaro.org wrote:
Hi Sumit,
On Thu, Jun 13, 2019 at 04:00:29PM +0530, Sumit Garg wrote:
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 this login method.
Signed-off-by: Sumit Garg sumit.garg@linaro.org
drivers/tee/tee_core.c | 6 ++++++ include/uapi/linux/tee.h | 2 ++ 2 files changed, 8 insertions(+)
diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c index 0f16d9f..4581bd1 100644 --- a/drivers/tee/tee_core.c +++ b/drivers/tee/tee_core.c @@ -334,6 +334,12 @@ static int tee_ioctl_open_session(struct tee_context *ctx, goto out; }
if (arg.clnt_login == TEE_IOCTL_LOGIN_REE_KERNEL) {
TEE_IOCTL_LOGIN_REE_KERNEL is defined as 0x80000000 which is in the range specified and implementation defined by the GP spec. I wonder if we shouldn't filter the entire implementation defined range instead of just this value.
Agree. Will rather check for entire implementation defined range: 0x80000000 - 0xFFFFFFFF.
I had a second thought on this. It would be more restrictive for user-space TEE client library which may need to use implementation defined login method. So either we could define specific ranges for kernel and user-space or we can start with single login method reserved for kernel.
I think we should reserve a range for kernel internal use. Only reserving a single single login for kernel could force us to restrict the API once more later, better to take a chunk now and be done with it. Half of 0x80000000 - 0xFFFFFFFF is probably more than enough too to leave a range for user space too.
pr_err("login method not allowed for user-space client\n");
pr_debug(), if it's needed at all.
Ok will use pr_debug() instead.
rc = -EPERM;
goto out;
}
rc = ctx->teedev->desc->ops->open_session(ctx, &arg, params); if (rc) goto out;
diff --git a/include/uapi/linux/tee.h b/include/uapi/linux/tee.h index 4b9eb06..f33c69c 100644 --- a/include/uapi/linux/tee.h +++ b/include/uapi/linux/tee.h @@ -172,6 +172,8 @@ 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 +/* Private login method for REE kernel clients */
It's worth noting that this is filtered by the TEE framework, compared to everything else which is treated opaquely.
IIUC, you are referring to login filter in optee_os. Change to prevent filter for this login method is part of this PR [1].
No, I was referring to the changes in tee_ioctl_open_session() above. It's relevant for user space to know since it will be prevented from using that range of login identifiers.
Ok, so you mean to extend the comment here for user-space to know that this login method/range is filtered by the TEE framework. Will do that.
This will restrict the user space API, but I think the risk of breakage is minimal as OP-TEE is the only in-tree driver registering in the TEE framework. I'm not aware of any out-of-tree drivers registering.
I am not sure if I follow you here. How do you expect this change to break out-of-tree TEE driver registration?
It's a change in common code that put restrictions on the API.
Thanks, Jens
-Sumit
Thanks, Jens
-Sumit
+#define TEE_IOCTL_LOGIN_REE_KERNEL 0x80000000
/**
- struct tee_ioctl_param - parameter
-- 2.7.4
Thanks, Jens
On Mon, 29 Jul 2019 at 12:39, Jens Wiklander jens.wiklander@linaro.org wrote:
Hi Sumit,
On Tue, Jul 9, 2019 at 11:36 AM Sumit Garg sumit.garg@linaro.org wrote:
On Tue, 9 Jul 2019 at 12:33, Jens Wiklander jens.wiklander@linaro.org wrote:
On Tue, Jul 09, 2019 at 11:26:19AM +0530, Sumit Garg wrote:
Thanks Jens for your comments.
On Mon, 8 Jul 2019 at 21:09, Jens Wiklander jens.wiklander@linaro.org wrote:
Hi Sumit,
On Thu, Jun 13, 2019 at 04:00:29PM +0530, Sumit Garg wrote:
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 this login method.
Signed-off-by: Sumit Garg sumit.garg@linaro.org
drivers/tee/tee_core.c | 6 ++++++ include/uapi/linux/tee.h | 2 ++ 2 files changed, 8 insertions(+)
diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c index 0f16d9f..4581bd1 100644 --- a/drivers/tee/tee_core.c +++ b/drivers/tee/tee_core.c @@ -334,6 +334,12 @@ static int tee_ioctl_open_session(struct tee_context *ctx, goto out; }
if (arg.clnt_login == TEE_IOCTL_LOGIN_REE_KERNEL) {
TEE_IOCTL_LOGIN_REE_KERNEL is defined as 0x80000000 which is in the range specified and implementation defined by the GP spec. I wonder if we shouldn't filter the entire implementation defined range instead of just this value.
Agree. Will rather check for entire implementation defined range: 0x80000000 - 0xFFFFFFFF.
I had a second thought on this. It would be more restrictive for user-space TEE client library which may need to use implementation defined login method. So either we could define specific ranges for kernel and user-space or we can start with single login method reserved for kernel.
I think we should reserve a range for kernel internal use. Only reserving a single single login for kernel could force us to restrict the API once more later, better to take a chunk now and be done with it. Half of 0x80000000 - 0xFFFFFFFF is probably more than enough too to leave a range for user space too.
Ok then, will rather reserve this range for kernel.
pr_err("login method not allowed for user-space client\n");
pr_debug(), if it's needed at all.
Ok will use pr_debug() instead.
rc = -EPERM;
goto out;
}
rc = ctx->teedev->desc->ops->open_session(ctx, &arg, params); if (rc) goto out;
diff --git a/include/uapi/linux/tee.h b/include/uapi/linux/tee.h index 4b9eb06..f33c69c 100644 --- a/include/uapi/linux/tee.h +++ b/include/uapi/linux/tee.h @@ -172,6 +172,8 @@ 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 +/* Private login method for REE kernel clients */
It's worth noting that this is filtered by the TEE framework, compared to everything else which is treated opaquely.
IIUC, you are referring to login filter in optee_os. Change to prevent filter for this login method is part of this PR [1].
No, I was referring to the changes in tee_ioctl_open_session() above. It's relevant for user space to know since it will be prevented from using that range of login identifiers.
Ok, so you mean to extend the comment here for user-space to know that this login method/range is filtered by the TEE framework. Will do that.
This will restrict the user space API, but I think the risk of breakage is minimal as OP-TEE is the only in-tree driver registering in the TEE framework. I'm not aware of any out-of-tree drivers registering.
I am not sure if I follow you here. How do you expect this change to break out-of-tree TEE driver registration?
It's a change in common code that put restrictions on the API.
Okay.
-Sumit
Thanks, Jens
-Sumit
Thanks, Jens
-Sumit
+#define TEE_IOCTL_LOGIN_REE_KERNEL 0x80000000
/**
- struct tee_ioctl_param - parameter
-- 2.7.4
Thanks, Jens
Add support for TEE based trusted keys where TEE provides the functionality to seal and unseal trusted keys using hardware unique key.
Refer to Documentation/tee.txt for detailed information about TEE.
Approach taken in this patch acts as an alternative to a TPM device in case platform doesn't possess one.
Signed-off-by: Sumit Garg sumit.garg@linaro.org --- include/keys/tee_trusted.h | 84 ++++++++ include/keys/trusted-type.h | 1 + security/keys/Kconfig | 3 + security/keys/Makefile | 3 + security/keys/tee_trusted.c | 506 ++++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 597 insertions(+) create mode 100644 include/keys/tee_trusted.h create mode 100644 security/keys/tee_trusted.c
diff --git a/include/keys/tee_trusted.h b/include/keys/tee_trusted.h new file mode 100644 index 0000000..e5c0042 --- /dev/null +++ b/include/keys/tee_trusted.h @@ -0,0 +1,84 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2019 Linaro Ltd. + * + * Author: + * Sumit Garg sumit.garg@linaro.org + */ + +#ifndef __TEE_TRUSTED_KEY_H +#define __TEE_TRUSTED_KEY_H + +#include <linux/tee_drv.h> + +#define DRIVER_NAME "tee-trusted-key" + +/* + * Get random data for symmetric key + * + * [out] memref[0] Random data + * + * Result: + * TEE_SUCCESS - Invoke command success + * TEE_ERROR_BAD_PARAMETERS - Incorrect input param + */ +#define TA_CMD_GET_RANDOM 0x0 + +/* + * Seal trusted key using hardware unique key + * + * [in] memref[0] Plain key + * [out] memref[1] Sealed key datablob + * + * Result: + * TEE_SUCCESS - Invoke command success + * TEE_ERROR_BAD_PARAMETERS - Incorrect input param + */ +#define TA_CMD_SEAL 0x1 + +/* + * Unseal trusted key using hardware unique key + * + * [in] memref[0] Sealed key datablob + * [out] memref[1] Plain key + * + * Result: + * TEE_SUCCESS - Invoke command success + * TEE_ERROR_BAD_PARAMETERS - Incorrect input param + */ +#define TA_CMD_UNSEAL 0x2 + +/** + * struct trusted_key_private - TEE Trusted key private data + * @dev: TEE based Trusted key device. + * @ctx: TEE context handler. + * @session_id: Trusted key TA session identifier. + * @shm_pool: Memory pool shared with TEE device. + */ +struct trusted_key_private { + struct device *dev; + struct tee_context *ctx; + u32 session_id; + u32 data_rate; + struct tee_shm *shm_pool; +}; + +#define TEE_KEY_DEBUG 0 + +#if TEE_KEY_DEBUG +static inline void dump_tee_payload(struct trusted_key_payload *p) +{ + pr_info("trusted_key: key_len %d\n", p->key_len); + print_hex_dump(KERN_INFO, "key ", DUMP_PREFIX_NONE, + 16, 1, p->key, p->key_len, 0); + pr_info("trusted_key: bloblen %d\n", p->blob_len); + print_hex_dump(KERN_INFO, "blob ", DUMP_PREFIX_NONE, + 16, 1, p->blob, p->blob_len, 0); +} +#else +static inline void dump_tee_payload(struct trusted_key_payload *p) +{ +} +#endif + +#endif diff --git a/include/keys/trusted-type.h b/include/keys/trusted-type.h index a94c03a..363ec83 100644 --- a/include/keys/trusted-type.h +++ b/include/keys/trusted-type.h @@ -41,5 +41,6 @@ struct trusted_key_options { };
extern struct key_type key_type_trusted; +extern struct key_type key_type_tee_trusted;
#endif /* _KEYS_TRUSTED_TYPE_H */ diff --git a/security/keys/Kconfig b/security/keys/Kconfig index ee502e4..b206a20 100644 --- a/security/keys/Kconfig +++ b/security/keys/Kconfig @@ -70,6 +70,9 @@ config TRUSTED_KEYS if the boot PCRs and other criteria match. Userspace will only ever see encrypted blobs.
+ It also provides support for alternative TEE based Trusted keys + generation and sealing in case TPM isn't present. + If you are unsure as to whether this is required, answer N.
config ENCRYPTED_KEYS diff --git a/security/keys/Makefile b/security/keys/Makefile index 9cef540..07ad3e2 100644 --- a/security/keys/Makefile +++ b/security/keys/Makefile @@ -30,3 +30,6 @@ obj-$(CONFIG_ASYMMETRIC_KEY_TYPE) += keyctl_pkey.o obj-$(CONFIG_BIG_KEYS) += big_key.o obj-$(CONFIG_TRUSTED_KEYS) += trusted.o obj-$(CONFIG_ENCRYPTED_KEYS) += encrypted-keys/ +ifdef CONFIG_TEE +obj-$(CONFIG_TRUSTED_KEYS) += tee_trusted.o +endif diff --git a/security/keys/tee_trusted.c b/security/keys/tee_trusted.c new file mode 100644 index 0000000..081e45e --- /dev/null +++ b/security/keys/tee_trusted.c @@ -0,0 +1,506 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 Linaro Ltd. + * + * Author: + * Sumit Garg sumit.garg@linaro.org + */ + +#include <linux/err.h> +#include <linux/key-type.h> +#include <linux/module.h> +#include <linux/parser.h> +#include <linux/rcupdate.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/tpm.h> +#include <linux/uaccess.h> +#include <linux/uuid.h> + +#include <keys/trusted-type.h> +#include <keys/user-type.h> +#include <keys/tee_trusted.h> + +static struct trusted_key_private pvt_data; + +/* + * Have the TEE seal(encrypt) the symmetric key + */ +static int tee_key_seal(struct trusted_key_payload *p) +{ + int ret = 0; + struct tee_ioctl_invoke_arg inv_arg; + struct tee_param param[4]; + struct tee_shm *reg_shm_in = NULL, *reg_shm_out = NULL; + + memset(&inv_arg, 0, sizeof(inv_arg)); + memset(¶m, 0, sizeof(param)); + + reg_shm_in = tee_shm_register(pvt_data.ctx, (unsigned long)p->key, + p->key_len, TEE_SHM_DMA_BUF | + TEE_SHM_KERNEL_MAPPED); + if (IS_ERR(reg_shm_in)) { + dev_err(pvt_data.dev, "key shm register failed\n"); + return PTR_ERR(reg_shm_in); + } + + reg_shm_out = tee_shm_register(pvt_data.ctx, (unsigned long)p->blob, + sizeof(p->blob), TEE_SHM_DMA_BUF | + TEE_SHM_KERNEL_MAPPED); + if (IS_ERR(reg_shm_out)) { + dev_err(pvt_data.dev, "blob shm register failed\n"); + ret = PTR_ERR(reg_shm_out); + goto out; + } + + inv_arg.func = TA_CMD_SEAL; + inv_arg.session = pvt_data.session_id; + inv_arg.num_params = 4; + + param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT; + param[0].u.memref.shm = reg_shm_in; + param[0].u.memref.size = p->key_len; + param[0].u.memref.shm_offs = 0; + param[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT; + param[1].u.memref.shm = reg_shm_out; + param[1].u.memref.size = sizeof(p->blob); + param[1].u.memref.shm_offs = 0; + + ret = tee_client_invoke_func(pvt_data.ctx, &inv_arg, param); + if ((ret < 0) || (inv_arg.ret != 0)) { + dev_err(pvt_data.dev, "TA_CMD_SEAL invoke err: %x\n", + inv_arg.ret); + ret = -EFAULT; + } else { + p->blob_len = param[1].u.memref.size; + } + +out: + if (reg_shm_out) + tee_shm_free(reg_shm_out); + if (reg_shm_in) + tee_shm_free(reg_shm_in); + + return ret; +} + +/* + * Have the TEE unseal(decrypt) the symmetric key + */ +static int tee_key_unseal(struct trusted_key_payload *p) +{ + int ret = 0; + struct tee_ioctl_invoke_arg inv_arg; + struct tee_param param[4]; + struct tee_shm *reg_shm_in = NULL, *reg_shm_out = NULL; + + memset(&inv_arg, 0, sizeof(inv_arg)); + memset(¶m, 0, sizeof(param)); + + reg_shm_in = tee_shm_register(pvt_data.ctx, (unsigned long)p->blob, + p->blob_len, TEE_SHM_DMA_BUF | + TEE_SHM_KERNEL_MAPPED); + if (IS_ERR(reg_shm_in)) { + dev_err(pvt_data.dev, "blob shm register failed\n"); + return PTR_ERR(reg_shm_in); + } + + reg_shm_out = tee_shm_register(pvt_data.ctx, (unsigned long)p->key, + sizeof(p->key), TEE_SHM_DMA_BUF | + TEE_SHM_KERNEL_MAPPED); + if (IS_ERR(reg_shm_out)) { + dev_err(pvt_data.dev, "key shm register failed\n"); + ret = PTR_ERR(reg_shm_out); + goto out; + } + + inv_arg.func = TA_CMD_UNSEAL; + inv_arg.session = pvt_data.session_id; + inv_arg.num_params = 4; + + param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT; + param[0].u.memref.shm = reg_shm_in; + param[0].u.memref.size = p->blob_len; + param[0].u.memref.shm_offs = 0; + param[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT; + param[1].u.memref.shm = reg_shm_out; + param[1].u.memref.size = sizeof(p->key); + param[1].u.memref.shm_offs = 0; + + ret = tee_client_invoke_func(pvt_data.ctx, &inv_arg, param); + if ((ret < 0) || (inv_arg.ret != 0)) { + dev_err(pvt_data.dev, "TA_CMD_UNSEAL invoke err: %x\n", + inv_arg.ret); + ret = -EFAULT; + } else { + p->key_len = param[1].u.memref.size; + } + +out: + if (reg_shm_out) + tee_shm_free(reg_shm_out); + if (reg_shm_in) + tee_shm_free(reg_shm_in); + + return ret; +} + +/* + * Have the TEE generate random symmetric key + */ +static int tee_get_random(unsigned char *key, unsigned int key_len) +{ + int ret = 0; + struct tee_ioctl_invoke_arg inv_arg; + struct tee_param param[4]; + struct tee_shm *reg_shm = NULL; + + memset(&inv_arg, 0, sizeof(inv_arg)); + memset(¶m, 0, sizeof(param)); + + reg_shm = tee_shm_register(pvt_data.ctx, (unsigned long)key, key_len, + TEE_SHM_DMA_BUF | TEE_SHM_KERNEL_MAPPED); + if (IS_ERR(reg_shm)) { + dev_err(pvt_data.dev, "random key shm register failed\n"); + return PTR_ERR(reg_shm); + } + + inv_arg.func = TA_CMD_GET_RANDOM; + inv_arg.session = pvt_data.session_id; + inv_arg.num_params = 4; + + param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT; + param[0].u.memref.shm = reg_shm; + param[0].u.memref.size = key_len; + param[0].u.memref.shm_offs = 0; + + ret = tee_client_invoke_func(pvt_data.ctx, &inv_arg, param); + if ((ret < 0) || (inv_arg.ret != 0)) { + dev_err(pvt_data.dev, "TA_CMD_GET_RANDOM invoke err: %x\n", + inv_arg.ret); + ret = -EFAULT; + } else { + ret = param[0].u.memref.size; + } + + tee_shm_free(reg_shm); + + return ret; +} + +enum { + Opt_err, + Opt_new, Opt_load +}; + +static const match_table_t key_tokens = { + {Opt_new, "new"}, + {Opt_load, "load"}, + {Opt_err, NULL} +}; + +/* + * datablob_parse - parse the keyctl data and fill in the + * payload structure + * + * On success returns 0, otherwise -EINVAL. + */ +static int datablob_parse(char *datablob, struct trusted_key_payload *p) +{ + substring_t args[MAX_OPT_ARGS]; + long keylen; + int ret = -EINVAL; + int key_cmd; + char *c; + + /* main command */ + c = strsep(&datablob, " \t"); + if (!c) + return -EINVAL; + + key_cmd = match_token(c, key_tokens, args); + switch (key_cmd) { + case Opt_new: + /* first argument is key size */ + c = strsep(&datablob, " \t"); + if (!c) + return -EINVAL; + ret = kstrtol(c, 10, &keylen); + if (ret < 0 || keylen < MIN_KEY_SIZE || keylen > MAX_KEY_SIZE) + return -EINVAL; + p->key_len = keylen; + ret = Opt_new; + break; + case Opt_load: + /* first argument is sealed blob */ + c = strsep(&datablob, " \t"); + if (!c) + return -EINVAL; + p->blob_len = strlen(c) / 2; + if (p->blob_len > MAX_BLOB_SIZE) + return -EINVAL; + ret = hex2bin(p->blob, c, p->blob_len); + if (ret < 0) + return -EINVAL; + ret = Opt_load; + break; + case Opt_err: + return -EINVAL; + } + + return ret; +} + +static struct trusted_key_payload *trusted_payload_alloc(struct key *key) +{ + struct trusted_key_payload *p = NULL; + int ret; + + ret = key_payload_reserve(key, sizeof(*p)); + if (ret < 0) + return p; + + p = kzalloc(sizeof(*p), GFP_KERNEL); + + return p; +} + +/* + * trusted_instantiate - create a new trusted key + * + * Unseal an existing trusted blob or, for a new key, get a + * random key, then seal and create a trusted key-type key, + * adding it to the specified keyring. + * + * On success, return 0. Otherwise return errno. + */ +static int trusted_instantiate(struct key *key, + struct key_preparsed_payload *prep) +{ + struct trusted_key_payload *payload = NULL; + size_t datalen = prep->datalen; + char *datablob; + int ret = 0; + int key_cmd; + size_t key_len; + + if (datalen <= 0 || datalen > 32767 || !prep->data) + return -EINVAL; + + datablob = kmalloc(datalen + 1, GFP_KERNEL); + if (!datablob) + return -ENOMEM; + memcpy(datablob, prep->data, datalen); + datablob[datalen] = '\0'; + + payload = trusted_payload_alloc(key); + if (!payload) { + ret = -ENOMEM; + goto out; + } + + key_cmd = datablob_parse(datablob, payload); + if (key_cmd < 0) { + ret = key_cmd; + goto out; + } + + dump_tee_payload(payload); + + switch (key_cmd) { + case Opt_load: + ret = tee_key_unseal(payload); + dump_tee_payload(payload); + if (ret < 0) + dev_err(pvt_data.dev, "key_unseal failed (%d)\n", ret); + break; + case Opt_new: + key_len = payload->key_len; + ret = tee_get_random(payload->key, key_len); + if (ret != key_len) { + dev_err(pvt_data.dev, "key_create failed (%d)\n", ret); + goto out; + } + + ret = tee_key_seal(payload); + if (ret < 0) + dev_err(pvt_data.dev, "key_seal failed (%d)\n", ret); + dump_tee_payload(payload); + break; + default: + ret = -EINVAL; + goto out; + } +out: + kzfree(datablob); + if (!ret) + rcu_assign_keypointer(key, payload); + else + kzfree(payload); + return ret; +} + +static int trusted_update(struct key *key, struct key_preparsed_payload *prep) +{ + dev_info(pvt_data.dev, "trusted key update method not supported\n"); + + return -EINVAL; +} + +/* + * trusted_read - copy the sealed blob data to userspace in hex. + * On success, return to userspace the trusted key datablob size. + */ +static long trusted_read(const struct key *key, char __user *buffer, + size_t buflen) +{ + const struct trusted_key_payload *p; + char *ascii_buf; + char *bufp; + int i; + + p = dereference_key_locked(key); + if (!p) + return -EINVAL; + + if (buffer && buflen >= 2 * p->blob_len) { + ascii_buf = kmalloc_array(2, p->blob_len, GFP_KERNEL); + if (!ascii_buf) + return -ENOMEM; + + bufp = ascii_buf; + for (i = 0; i < p->blob_len; i++) + bufp = hex_byte_pack(bufp, p->blob[i]); + if (copy_to_user(buffer, ascii_buf, 2 * p->blob_len) != 0) { + kzfree(ascii_buf); + return -EFAULT; + } + kzfree(ascii_buf); + } + return 2 * p->blob_len; +} + +/* + * trusted_destroy - clear and free the key's payload + */ +static void trusted_destroy(struct key *key) +{ + kzfree(key->payload.data[0]); +} + +struct key_type key_type_tee_trusted = { + .name = "trusted", + .instantiate = trusted_instantiate, + .update = trusted_update, + .destroy = trusted_destroy, + .describe = user_describe, + .read = trusted_read, +}; +EXPORT_SYMBOL_GPL(key_type_tee_trusted); + +static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data) +{ + if (ver->impl_id == TEE_IMPL_ID_OPTEE) + return 1; + else + return 0; +} + +static int trusted_key_probe(struct device *dev) +{ + struct tee_client_device *rng_device = to_tee_client_device(dev); + int ret = 0, err = -ENODEV; + struct tee_ioctl_open_session_arg sess_arg; + + memset(&sess_arg, 0, sizeof(sess_arg)); + + /* Open context with TEE driver */ + pvt_data.ctx = tee_client_open_context(NULL, optee_ctx_match, NULL, + NULL); + if (IS_ERR(pvt_data.ctx)) + return -ENODEV; + + /* Open session with hwrng Trusted App */ + memcpy(sess_arg.uuid, rng_device->id.uuid.b, TEE_IOCTL_UUID_LEN); + sess_arg.clnt_login = TEE_IOCTL_LOGIN_REE_KERNEL; + sess_arg.num_params = 0; + + ret = tee_client_open_session(pvt_data.ctx, &sess_arg, NULL); + if ((ret < 0) || (sess_arg.ret != 0)) { + dev_err(dev, "tee_client_open_session failed, err: %x\n", + sess_arg.ret); + err = -EINVAL; + goto out_ctx; + } + pvt_data.session_id = sess_arg.session; + + ret = register_key_type(&key_type_tee_trusted); + if (ret < 0) + goto out_sess; + + pvt_data.dev = dev; + + return 0; + +out_sess: + tee_client_close_session(pvt_data.ctx, pvt_data.session_id); +out_ctx: + tee_client_close_context(pvt_data.ctx); + + return err; +} + +static int trusted_key_remove(struct device *dev) +{ + unregister_key_type(&key_type_tee_trusted); + tee_client_close_session(pvt_data.ctx, pvt_data.session_id); + tee_client_close_context(pvt_data.ctx); + + return 0; +} + +static const struct tee_client_device_id trusted_key_id_table[] = { + {UUID_INIT(0xf04a0fe7, 0x1f5d, 0x4b9b, + 0xab, 0xf7, 0x61, 0x9b, 0x85, 0xb4, 0xce, 0x8c)}, + {} +}; + +MODULE_DEVICE_TABLE(tee, trusted_key_id_table); + +static struct tee_client_driver trusted_key_driver = { + .id_table = trusted_key_id_table, + .driver = { + .name = DRIVER_NAME, + .bus = &tee_bus_type, + .probe = trusted_key_probe, + .remove = trusted_key_remove, + }, +}; + +static int __init init_tee_trusted(void) +{ + struct tpm_chip *chip; + + /* + * Check for TPM availability as that is default source for trusted + * keys. If not present, then register driver for TEE based device + * providing support for trusted keys. + */ + chip = tpm_default_chip(); + if (chip) + return 0; + + return driver_register(&trusted_key_driver.driver); +} + +static void __exit cleanup_tee_trusted(void) +{ + driver_unregister(&trusted_key_driver.driver); +} + +late_initcall(init_tee_trusted); +module_exit(cleanup_tee_trusted); + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Sumit Garg sumit.garg@linaro.org"); +MODULE_DESCRIPTION("TEE based trusted keys");
On Thu, Jun 13, 2019 at 04:00:30PM +0530, Sumit Garg wrote:
Add support for TEE based trusted keys where TEE provides the functionality to seal and unseal trusted keys using hardware unique key.
Refer to Documentation/tee.txt for detailed information about TEE.
Approach taken in this patch acts as an alternative to a TPM device in case platform doesn't possess one.
Signed-off-by: Sumit Garg sumit.garg@linaro.org
How does this interact with the trusted module? Why there is no update to security/keys/trusted-encrypted.txt?
Somehow the existing trusted module needs to be re-architected to work with either. Otherwise, this will turn out to be a mess.
/Jarkko
On Thu, 13 Jun 2019 at 21:02, Jarkko Sakkinen jarkko.sakkinen@linux.intel.com wrote:
On Thu, Jun 13, 2019 at 04:00:30PM +0530, Sumit Garg wrote:
Add support for TEE based trusted keys where TEE provides the functionality to seal and unseal trusted keys using hardware unique key.
Refer to Documentation/tee.txt for detailed information about TEE.
Approach taken in this patch acts as an alternative to a TPM device in case platform doesn't possess one.
Signed-off-by: Sumit Garg sumit.garg@linaro.org
How does this interact with the trusted module? Why there is no update to security/keys/trusted-encrypted.txt?
You already found documentation patch [1].
Somehow the existing trusted module needs to be re-architected to work with either. Otherwise, this will turn out to be a mess.
See my reply on this patch [1].
[1] [RFC 6/7] doc: keys: Document usage of TEE based Trusted Keys
-Sumit
/Jarkko
Allow search for TEE based trusted keys to act as master keys in case TPM device is not present.
Signed-off-by: Sumit Garg sumit.garg@linaro.org --- security/keys/encrypted-keys/masterkey_trusted.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/security/keys/encrypted-keys/masterkey_trusted.c b/security/keys/encrypted-keys/masterkey_trusted.c index c68528a..cfac27f 100644 --- a/security/keys/encrypted-keys/masterkey_trusted.c +++ b/security/keys/encrypted-keys/masterkey_trusted.c @@ -23,6 +23,9 @@ * Trusted keys are sealed to PCRs and other metadata. Although userspace * manages both trusted/encrypted key-types, like the encrypted key type * data, trusted key type data is not visible decrypted from userspace. + * + * Also, check for alternate trusted keys provided via TEE in case there + * is no TPM available. */ struct key *request_trusted_key(const char *trusted_desc, const u8 **master_key, size_t *master_keylen) @@ -31,8 +34,11 @@ struct key *request_trusted_key(const char *trusted_desc, struct key *tkey;
tkey = request_key(&key_type_trusted, trusted_desc, NULL); - if (IS_ERR(tkey)) - goto error; + if (IS_ERR(tkey)) { + tkey = request_key(&key_type_tee_trusted, trusted_desc, NULL); + if (IS_ERR(tkey)) + goto error; + }
down_read(&tkey->sem); tpayload = tkey->payload.data[0];
Provide documentation for usage of TEE based Trusted Keys via existing user-space "keyctl" utility. Also, document various use-cases.
Signed-off-by: Sumit Garg sumit.garg@linaro.org --- Documentation/security/keys/tee-trusted.rst | 93 +++++++++++++++++++++++++++++ 1 file changed, 93 insertions(+) create mode 100644 Documentation/security/keys/tee-trusted.rst
diff --git a/Documentation/security/keys/tee-trusted.rst b/Documentation/security/keys/tee-trusted.rst new file mode 100644 index 0000000..ef03745 --- /dev/null +++ b/Documentation/security/keys/tee-trusted.rst @@ -0,0 +1,93 @@ +====================== +TEE based Trusted Keys +====================== + +TEE based Trusted Keys provides an alternative approach for providing Trusted +Keys in case TPM chip isn't present. + +Trusted Keys use a TEE service/device both to generate and to seal the keys. +Keys are sealed under a hardware unique key in the TEE, and only unsealed by +the TEE. + +For more information about TEE, refer to ``Documentation/tee.txt``. + +Usage:: + + keyctl add trusted name "new keylen" ring + keyctl add trusted name "load hex_blob" ring + keyctl print keyid + +"keyctl print" returns an ascii hex copy of the sealed key, which is in format +specific to TEE device implementation. The key length for new keys are always +in bytes. Trusted Keys can be 32 - 128 bytes (256 - 1024 bits). + +Examples of trusted key and its usage as 'master' key for encrypted key usage: + +More details about encrypted keys can be found here: +``Documentation/security/keys/trusted-encrypted.rst`` + +Create and save a trusted key named "kmk" of length 32 bytes:: + + $ keyctl add trusted kmk "new 32" @u + 754414669 + + $ keyctl show + Session Keyring + 827385718 --alswrv 0 65534 keyring: _uid_ses.0 + 274124851 --alswrv 0 65534 _ keyring: _uid.0 + 754414669 --als-rv 0 0 _ trusted: kmk + + $ keyctl print 754414669 + 15676790697861b422175596ae001c2f505cea2c6f3ebbc5fb08eeb1f343a07e + + $ keyctl pipe 754414669 > kmk.blob + +Load a trusted key from the saved blob:: + + $ keyctl add trusted kmk "load `cat kmk.blob`" @u + 491638700 + + $ keyctl print 491638700 + 15676790697861b422175596ae001c2f505cea2c6f3ebbc5fb08eeb1f343a07e + +The initial consumer of trusted keys is EVM, which at boot time needs a high +quality symmetric key for HMAC protection of file metadata. The use of a +TEE based trusted key provides security that the EVM key has not been +compromised by a user level problem and tied to particular hardware. + +Create and save an encrypted key "evm" using the above trusted key "kmk": + +option 1: omitting 'format':: + + $ keyctl add encrypted evm "new trusted:kmk 32" @u + 608915065 + +option 2: explicitly defining 'format' as 'default':: + + $ keyctl add encrypted evm "new default trusted:kmk 32" @u + 608915065 + + $ keyctl print 608915065 + default trusted:kmk 32 f380ac588a925f488d5be007cf23e4c900b8b652ab62241c8 + ed54906189b6659d139d619d4b51752a2645537b11fd44673f13154a65b3f595d5fb2131 + 2fe45529ea0407c644ea4026f2a1a75661f2c9b66 + + $ keyctl pipe 608915065 > evm.blob + +Load an encrypted key "evm" from saved blob:: + + $ keyctl add encrypted evm "load `cat evm.blob`" @u + 831684262 + + $ keyctl print 831684262 + default trusted:kmk 32 f380ac588a925f488d5be007cf23e4c900b8b652ab62241c8 + ed54906189b6659d139d619d4b51752a2645537b11fd44673f13154a65b3f595d5fb2131 + 2fe45529ea0407c644ea4026f2a1a75661f2c9b66 + +Other uses for trusted and encrypted keys, such as for disk and file encryption +are anticipated. In particular the 'ecryptfs' encrypted keys format can be used +to mount an eCryptfs filesystem. More details about the usage can be found in +the file ``Documentation/security/keys/ecryptfs.rst``. + +Another format 'enc32' can be used to support encrypted keys with payload size +of 32 bytes.
On Thu, Jun 13, 2019 at 04:00:32PM +0530, Sumit Garg wrote:
Provide documentation for usage of TEE based Trusted Keys via existing user-space "keyctl" utility. Also, document various use-cases.
Signed-off-by: Sumit Garg sumit.garg@linaro.org
Sorry missed this patch. Anyway, I don't think we want multiple trusted keys subsystems. You have to fix the existing one if you care to get these changes in. There is no really other way around this.
/Jarkko
On Thu, 13 Jun 2019 at 21:04, Jarkko Sakkinen jarkko.sakkinen@linux.intel.com wrote:
On Thu, Jun 13, 2019 at 04:00:32PM +0530, Sumit Garg wrote:
Provide documentation for usage of TEE based Trusted Keys via existing user-space "keyctl" utility. Also, document various use-cases.
Signed-off-by: Sumit Garg sumit.garg@linaro.org
Sorry missed this patch. Anyway, I don't think we want multiple trusted keys subsystems. You have to fix the existing one if you care to get these changes in. There is no really other way around this.
I understand your point.
When I initially looked at trusted key implementation, it seemed to be tightly coupled to use TPM device. So I implemented a parallel implementation to get initial feedback (functionality-wise) on this new approach.
I will work on abstraction of trusted key apis to use either approach. But is it fine with you if I send if I send a separate RFC patch for abstraction and later once reviewed I will incorporate that patch in this patch-set.
It will be really helpful if you could help to test that abstraction patch with a real TPM device as I doesn't posses one to test.
-Sumit
/Jarkko
On Fri, Jun 14, 2019 at 11:07:23AM +0530, Sumit Garg wrote:
On Thu, 13 Jun 2019 at 21:04, Jarkko Sakkinen jarkko.sakkinen@linux.intel.com wrote:
On Thu, Jun 13, 2019 at 04:00:32PM +0530, Sumit Garg wrote:
Provide documentation for usage of TEE based Trusted Keys via existing user-space "keyctl" utility. Also, document various use-cases.
Signed-off-by: Sumit Garg sumit.garg@linaro.org
Sorry missed this patch. Anyway, I don't think we want multiple trusted keys subsystems. You have to fix the existing one if you care to get these changes in. There is no really other way around this.
I understand your point.
When I initially looked at trusted key implementation, it seemed to be tightly coupled to use TPM device. So I implemented a parallel implementation to get initial feedback (functionality-wise) on this new approach.
Yeah, I completely get this. My feedback this is: we can definitely consider TEE based trusted keys, and I know that trusted.ko is a mess, but still that is the only right long-term path. Think about the positive side: if you as a side-effect can make it cleaner and more versatile, your patch set will improve the quality of the kernel as a whole i.e. you benefit larger audience than just TEE user base :-)
I will work on abstraction of trusted key apis to use either approach. But is it fine with you if I send if I send a separate RFC patch for abstraction and later once reviewed I will incorporate that patch in this patch-set.
It will be really helpful if you could help to test that abstraction patch with a real TPM device as I doesn't posses one to test.
I can, yes.
/Jarkko
Add MAINTAINERS entry for TEE based Trusted Keys framework.
Signed-off-by: Sumit Garg sumit.garg@linaro.org --- MAINTAINERS | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/MAINTAINERS b/MAINTAINERS index 57f496c..db84fc4 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -8728,6 +8728,15 @@ F: include/keys/trusted-type.h F: security/keys/trusted.c F: security/keys/trusted.h
+KEYS-TEE-TRUSTED +M: Sumit Garg sumit.garg@linaro.org +L: linux-integrity@vger.kernel.org +L: keyrings@vger.kernel.org +S: Supported +F: Documentation/security/keys/tee-trusted.rst +F: include/keys/tee_trusted.h +F: security/keys/tee_trusted.c + KEYS/KEYRINGS: M: David Howells dhowells@redhat.com L: keyrings@vger.kernel.org
On 6/13/2019 3:30 AM, Sumit Garg wrote:
Add support for TEE based trusted keys where TEE provides the functionality to seal and unseal trusted keys using hardware unique key. Also, this is an alternative in case platform doesn't possess a TPM device.
This series also adds some TEE features like:
Please expand the acronym TEE on first use. That will help people who don't work with it on a daily basis understand what you're going on about.
Patch #1, #2 enables support for registered kernel shared memory with TEE.
Patch #3 enables support for private kernel login method required for cases like trusted keys where we don't wan't user-space to directly access TEE service to retrieve trusted key contents.
Rest of the patches from #4 to #7 adds support for TEE based trusted keys.
This patch-set has been tested with OP-TEE based pseudo TA which can be found here [1].
Looking forward to your valuable feedback/suggestions.
[1] https://github.com/OP-TEE/optee_os/pull/3082
Sumit Garg (7): tee: optee: allow kernel pages to register as shm tee: enable support to register kernel memory tee: add private login method for kernel clients KEYS: trusted: Introduce TEE based Trusted Keys KEYS: encrypted: Allow TEE based trusted master keys doc: keys: Document usage of TEE based Trusted Keys MAINTAINERS: Add entry for TEE based Trusted Keys
Documentation/security/keys/tee-trusted.rst | 93 +++++ MAINTAINERS | 9 + drivers/tee/optee/call.c | 7 + drivers/tee/tee_core.c | 6 + drivers/tee/tee_shm.c | 16 +- include/keys/tee_trusted.h | 84 ++++ include/keys/trusted-type.h | 1 + include/linux/tee_drv.h | 1 + include/uapi/linux/tee.h | 2 + security/keys/Kconfig | 3 + security/keys/Makefile | 3 + security/keys/encrypted-keys/masterkey_trusted.c | 10 +- security/keys/tee_trusted.c | 506 +++++++++++++++++++++++ 13 files changed, 737 insertions(+), 4 deletions(-) create mode 100644 Documentation/security/keys/tee-trusted.rst create mode 100644 include/keys/tee_trusted.h create mode 100644 security/keys/tee_trusted.c
On Thu, 2019-06-13 at 09:40 -0700, Casey Schaufler wrote:
On 6/13/2019 3:30 AM, Sumit Garg wrote:
Add support for TEE based trusted keys where TEE provides the functionality to seal and unseal trusted keys using hardware unique key. Also, this is an alternative in case platform doesn't possess a TPM device.
This series also adds some TEE features like:
Please expand the acronym TEE on first use. That will help people who don't work with it on a daily basis understand what you're going on about.
Thanks, Casey.
"[6/7] doc: keys: Document usage of TEE based Trusted Keys" refers to the kernel tee documentation, but that documentation is limited to userspace interaction with the tee.
A trusted key is a random number generated and sealed(encrypted) by the TPM, so that only the TPM may unseal it. The sealing key never leaves the TPM. The sealed, trusted key may be exported to userspace. In the tee case, can the "sealing" key ever leave the tee? Can the sealed, trusted key, exported to userspace, be unsealed by the tee? Are the tee security protections similar to those of the TPM? How do they compare?
Mimi
Patch #1, #2 enables support for registered kernel shared memory with TEE.
Patch #3 enables support for private kernel login method required for cases like trusted keys where we don't wan't user-space to directly access TEE service to retrieve trusted key contents.
Rest of the patches from #4 to #7 adds support for TEE based trusted keys.
This patch-set has been tested with OP-TEE based pseudo TA which can be found here [1].
Looking forward to your valuable feedback/suggestions.
Thanks Mimi for your comments.
On Fri, 14 Jun 2019 at 05:33, Mimi Zohar zohar@linux.ibm.com wrote:
On Thu, 2019-06-13 at 09:40 -0700, Casey Schaufler wrote:
On 6/13/2019 3:30 AM, Sumit Garg wrote:
Add support for TEE based trusted keys where TEE provides the functionality to seal and unseal trusted keys using hardware unique key. Also, this is an alternative in case platform doesn't possess a TPM device.
This series also adds some TEE features like:
Please expand the acronym TEE on first use. That will help people who don't work with it on a daily basis understand what you're going on about.
Thanks, Casey.
"[6/7] doc: keys: Document usage of TEE based Trusted Keys" refers to the kernel tee documentation, but that documentation is limited to userspace interaction with the tee.
Thanks for pointing this out. I will update documentation to include TEE bus approach and communication apis for kernel clients.
BTW, the interface is similar as with user-space. Only difference is instead of IOCTL's from user-space, there are wrapper apis to communicate with TEE.
Also, in case someone is interested to learn about TEE technology, this webinar [1] could be one of starting points.
A trusted key is a random number generated and sealed(encrypted) by the TPM, so that only the TPM may unseal it. The sealing key never leaves the TPM. The sealed, trusted key may be exported to userspace.
Understood.
In the tee case, can the "sealing" key ever leave the tee?
No, the "sealing" key never leaves TEE. Its basically a Hardware Unique Key (HUK) tied to a particular SoC.
Can the sealed, trusted key, exported to userspace, be unsealed by the tee?
You mean using user-space interface to TEE? If yes, then answer is "no" as user-space can't communicate with this TEE service as its accessible to kernel clients only (see patch [2]).
In case you meant loading exported trusted key blob via "keyctl", then "yes" this driver can unseal the trusted key. Have a look at examples I have listed in documentation patch [3]. Also, this approach works well across power cycles too.
Are the tee security protections similar to those of the TPM? How do they compare?
Let me try to compare both environments. Regarding TEE, I will refer to OP-TEE [4] as one of its implementation.
TPM:
1. External hardware. 2. Sealing key resides inside TPM. 3. Communicates via SPI, I2C etc.
OP-TEE:
1. On chip, trusted execution environment enforced via ARM TrustZone. 2. Sealing key is unique to a particular SoC provided by secure fuses, secure crypto engine etc. 3. Communicates via Secure Monitor Calls (SMCs [5]).
[1] https://globalplatform.org/resource-publication/webinar-an-introduction-to-t... [2] [RFC 3/7] tee: add private login method for kernel clients [3] [RFC 6/7] doc: keys: Document usage of TEE based Trusted Keys [4] https://optee.readthedocs.io/general/about.html [5] http://infocenter.arm.com/help/topic/com.arm.doc.den0028b/ARM_DEN0028B_SMC_C...
-Sumit
Mimi
Patch #1, #2 enables support for registered kernel shared memory with TEE.
Patch #3 enables support for private kernel login method required for cases like trusted keys where we don't wan't user-space to directly access TEE service to retrieve trusted key contents.
Rest of the patches from #4 to #7 adds support for TEE based trusted keys.
This patch-set has been tested with OP-TEE based pseudo TA which can be found here [1].
Looking forward to your valuable feedback/suggestions.
On Thu, 13 Jun 2019 at 22:10, Casey Schaufler casey@schaufler-ca.com wrote:
On 6/13/2019 3:30 AM, Sumit Garg wrote:
Add support for TEE based trusted keys where TEE provides the functionality to seal and unseal trusted keys using hardware unique key. Also, this is an alternative in case platform doesn't possess a TPM device.
This series also adds some TEE features like:
Please expand the acronym TEE on first use. That will help people who don't work with it on a daily basis understand what you're going on about.
Sure will take care of this. BTW, its Trusted Execution Environment (TEE).
-Sumit
Patch #1, #2 enables support for registered kernel shared memory with TEE.
Patch #3 enables support for private kernel login method required for cases like trusted keys where we don't wan't user-space to directly access TEE service to retrieve trusted key contents.
Rest of the patches from #4 to #7 adds support for TEE based trusted keys.
This patch-set has been tested with OP-TEE based pseudo TA which can be found here [1].
Looking forward to your valuable feedback/suggestions.
[1] https://github.com/OP-TEE/optee_os/pull/3082
Sumit Garg (7): tee: optee: allow kernel pages to register as shm tee: enable support to register kernel memory tee: add private login method for kernel clients KEYS: trusted: Introduce TEE based Trusted Keys KEYS: encrypted: Allow TEE based trusted master keys doc: keys: Document usage of TEE based Trusted Keys MAINTAINERS: Add entry for TEE based Trusted Keys
Documentation/security/keys/tee-trusted.rst | 93 +++++ MAINTAINERS | 9 + drivers/tee/optee/call.c | 7 + drivers/tee/tee_core.c | 6 + drivers/tee/tee_shm.c | 16 +- include/keys/tee_trusted.h | 84 ++++ include/keys/trusted-type.h | 1 + include/linux/tee_drv.h | 1 + include/uapi/linux/tee.h | 2 + security/keys/Kconfig | 3 + security/keys/Makefile | 3 + security/keys/encrypted-keys/masterkey_trusted.c | 10 +- security/keys/tee_trusted.c | 506 +++++++++++++++++++++++ 13 files changed, 737 insertions(+), 4 deletions(-) create mode 100644 Documentation/security/keys/tee-trusted.rst create mode 100644 include/keys/tee_trusted.h create mode 100644 security/keys/tee_trusted.c
Hi Jens,
On Thu, 13 Jun 2019 at 16:01, Sumit Garg sumit.garg@linaro.org wrote:
Add support for TEE based trusted keys where TEE provides the functionality to seal and unseal trusted keys using hardware unique key. Also, this is an alternative in case platform doesn't possess a TPM device.
This series also adds some TEE features like:
Patch #1, #2 enables support for registered kernel shared memory with TEE.
Would you like to pick up Patch #1, #2 separately? I think both these patches add independent functionality and also got reviewed-by tags too.
-Sumit
Patch #3 enables support for private kernel login method required for cases like trusted keys where we don't wan't user-space to directly access TEE service to retrieve trusted key contents.
Rest of the patches from #4 to #7 adds support for TEE based trusted keys.
This patch-set has been tested with OP-TEE based pseudo TA which can be found here [1].
Looking forward to your valuable feedback/suggestions.
[1] https://github.com/OP-TEE/optee_os/pull/3082
Sumit Garg (7): tee: optee: allow kernel pages to register as shm tee: enable support to register kernel memory tee: add private login method for kernel clients KEYS: trusted: Introduce TEE based Trusted Keys KEYS: encrypted: Allow TEE based trusted master keys doc: keys: Document usage of TEE based Trusted Keys MAINTAINERS: Add entry for TEE based Trusted Keys
Documentation/security/keys/tee-trusted.rst | 93 +++++ MAINTAINERS | 9 + drivers/tee/optee/call.c | 7 + drivers/tee/tee_core.c | 6 + drivers/tee/tee_shm.c | 16 +- include/keys/tee_trusted.h | 84 ++++ include/keys/trusted-type.h | 1 + include/linux/tee_drv.h | 1 + include/uapi/linux/tee.h | 2 + security/keys/Kconfig | 3 + security/keys/Makefile | 3 + security/keys/encrypted-keys/masterkey_trusted.c | 10 +- security/keys/tee_trusted.c | 506 +++++++++++++++++++++++ 13 files changed, 737 insertions(+), 4 deletions(-) create mode 100644 Documentation/security/keys/tee-trusted.rst create mode 100644 include/keys/tee_trusted.h create mode 100644 security/keys/tee_trusted.c
-- 2.7.4
Hi Sumit,
On Mon, Jul 08, 2019 at 06:11:39PM +0530, Sumit Garg wrote:
Hi Jens,
On Thu, 13 Jun 2019 at 16:01, Sumit Garg sumit.garg@linaro.org wrote:
Add support for TEE based trusted keys where TEE provides the functionality to seal and unseal trusted keys using hardware unique key. Also, this is an alternative in case platform doesn't possess a TPM device.
This series also adds some TEE features like:
Patch #1, #2 enables support for registered kernel shared memory with TEE.
Would you like to pick up Patch #1, #2 separately? I think both these patches add independent functionality and also got reviewed-by tags too.
I think it makes more sense to keep them together in the same patch series or could end up with dependencies between trees.
If you don't think dependencies will be an issue then I don't mind picking them up, in that case they'd likely sit in an arm-soc branch until next merge window. However, I think that #3 (support for private kernel login method) should be included too and that one isn't ready yet.
Thanks, Jens
-Sumit
Patch #3 enables support for private kernel login method required for cases like trusted keys where we don't wan't user-space to directly access TEE service to retrieve trusted key contents.
Rest of the patches from #4 to #7 adds support for TEE based trusted keys.
This patch-set has been tested with OP-TEE based pseudo TA which can be found here [1].
Looking forward to your valuable feedback/suggestions.
[1] https://github.com/OP-TEE/optee_os/pull/3082
Sumit Garg (7): tee: optee: allow kernel pages to register as shm tee: enable support to register kernel memory tee: add private login method for kernel clients KEYS: trusted: Introduce TEE based Trusted Keys KEYS: encrypted: Allow TEE based trusted master keys doc: keys: Document usage of TEE based Trusted Keys MAINTAINERS: Add entry for TEE based Trusted Keys
Documentation/security/keys/tee-trusted.rst | 93 +++++ MAINTAINERS | 9 + drivers/tee/optee/call.c | 7 + drivers/tee/tee_core.c | 6 + drivers/tee/tee_shm.c | 16 +- include/keys/tee_trusted.h | 84 ++++ include/keys/trusted-type.h | 1 + include/linux/tee_drv.h | 1 + include/uapi/linux/tee.h | 2 + security/keys/Kconfig | 3 + security/keys/Makefile | 3 + security/keys/encrypted-keys/masterkey_trusted.c | 10 +- security/keys/tee_trusted.c | 506 +++++++++++++++++++++++ 13 files changed, 737 insertions(+), 4 deletions(-) create mode 100644 Documentation/security/keys/tee-trusted.rst create mode 100644 include/keys/tee_trusted.h create mode 100644 security/keys/tee_trusted.c
-- 2.7.4
On Mon, 8 Jul 2019 at 22:01, Jens Wiklander jens.wiklander@linaro.org wrote:
Hi Sumit,
On Mon, Jul 08, 2019 at 06:11:39PM +0530, Sumit Garg wrote:
Hi Jens,
On Thu, 13 Jun 2019 at 16:01, Sumit Garg sumit.garg@linaro.org wrote:
Add support for TEE based trusted keys where TEE provides the functionality to seal and unseal trusted keys using hardware unique key. Also, this is an alternative in case platform doesn't possess a TPM device.
This series also adds some TEE features like:
Patch #1, #2 enables support for registered kernel shared memory with TEE.
Would you like to pick up Patch #1, #2 separately? I think both these patches add independent functionality and also got reviewed-by tags too.
I think it makes more sense to keep them together in the same patch series or could end up with dependencies between trees.
I understand your point. Let me keep this patch-set together to avoid any dependencies.
-Sumit
If you don't think dependencies will be an issue then I don't mind picking them up, in that case they'd likely sit in an arm-soc branch until next merge window. However, I think that #3 (support for private kernel login method) should be included too and that one isn't ready yet.
Thanks, Jens
-Sumit
Patch #3 enables support for private kernel login method required for cases like trusted keys where we don't wan't user-space to directly access TEE service to retrieve trusted key contents.
Rest of the patches from #4 to #7 adds support for TEE based trusted keys.
This patch-set has been tested with OP-TEE based pseudo TA which can be found here [1].
Looking forward to your valuable feedback/suggestions.
[1] https://github.com/OP-TEE/optee_os/pull/3082
Sumit Garg (7): tee: optee: allow kernel pages to register as shm tee: enable support to register kernel memory tee: add private login method for kernel clients KEYS: trusted: Introduce TEE based Trusted Keys KEYS: encrypted: Allow TEE based trusted master keys doc: keys: Document usage of TEE based Trusted Keys MAINTAINERS: Add entry for TEE based Trusted Keys
Documentation/security/keys/tee-trusted.rst | 93 +++++ MAINTAINERS | 9 + drivers/tee/optee/call.c | 7 + drivers/tee/tee_core.c | 6 + drivers/tee/tee_shm.c | 16 +- include/keys/tee_trusted.h | 84 ++++ include/keys/trusted-type.h | 1 + include/linux/tee_drv.h | 1 + include/uapi/linux/tee.h | 2 + security/keys/Kconfig | 3 + security/keys/Makefile | 3 + security/keys/encrypted-keys/masterkey_trusted.c | 10 +- security/keys/tee_trusted.c | 506 +++++++++++++++++++++++ 13 files changed, 737 insertions(+), 4 deletions(-) create mode 100644 Documentation/security/keys/tee-trusted.rst create mode 100644 include/keys/tee_trusted.h create mode 100644 security/keys/tee_trusted.c
-- 2.7.4