OrgACRN
/
acrn-kernel
mirror of https://github.com/projectacrn/acrn-kernel.git
1
0
Fork 0
Code Issues Releases Wiki Activity

selftests/sgx: Make data measurement for an enclave segment optional 

For a heap makes sense to leave its contents "unmeasured" in the SGX
enclave build process, meaning that they won't contribute to the
cryptographic signature (a RSA-3072 signed SHA56 hash) of the enclave.

Enclaves are signed blobs where the signature is calculated both from
page data and also from "structural properties" of the pages.  For
instance a page offset of *every* page added to the enclave is hashed.

For data, this is optional, not least because hashing a page has a
significant contribution to the enclave load time. Thus, where there is
no reason to hash, do not. The SGX ioctl interface supports this with
SGX_PAGE_MEASURE flag. Only when the flag is *set*, data is measured.

Add seg->measure boolean flag to struct encl_segment. Only when the
flag is set, include the segment data to the signature (represented
by SIGSTRUCT architectural structure).

Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lkml.kernel.org/r/625b6fe28fed76275e9238ec4e15ec3c0d87de81.1636997631.git.reinette.chatre@intel.com
This commit is contained in:
Jarkko Sakkinen 2021-11-15 10:35:16 -08:00 committed by Dave Hansen
parent 39f62536be
commit 5f0ce664d8
3 changed files with 10 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
tools/testing/selftests/sgx/load.c
View File

@ -111,7 +111,10 @@ static bool encl_ioc_add_pages(struct encl *encl, struct encl_segment *seg)
ioc.offset = seg->offset;
ioc.length = seg->size;
ioc.secinfo = (unsigned long)&secinfo;
ioc.flags = SGX_PAGE_MEASURE;
if (seg->measure)
ioc.flags = SGX_PAGE_MEASURE;
else
ioc.flags = 0;
rc = ioctl(encl->fd, SGX_IOC_ENCLAVE_ADD_PAGES, &ioc);
if (rc < 0) {
@ -230,6 +233,7 @@ bool encl_load(const char *path, struct encl *encl)
seg->offset = (phdr->p_offset & PAGE_MASK) - src_offset;
seg->size = (phdr->p_filesz + PAGE_SIZE - 1) & PAGE_MASK;
seg->src = encl->src + seg->offset;
seg->measure = true;
j++;
}

1
tools/testing/selftests/sgx/main.h
View File

@ -12,6 +12,7 @@ struct encl_segment {
size_t size;
unsigned int prot;
unsigned int flags;
bool measure;
};
struct encl {

6
tools/testing/selftests/sgx/sigstruct.c
View File

@ -296,8 +296,10 @@ static bool mrenclave_segment(EVP_MD_CTX *ctx, struct encl *encl,
if (!mrenclave_eadd(ctx, seg->offset + offset, seg->flags))
return false;
if (!mrenclave_eextend(ctx, seg->offset + offset, seg->src + offset))
return false;
if (seg->measure) {
if (!mrenclave_eextend(ctx, seg->offset + offset, seg->src + offset))
return false;
}
}
return true;