ima: platform-independent hash value

For remote attestion it is important for the ima measurement values to
be platform-independent.  Therefore integer fields to be hashed must be
converted to canonical format.

Link: http://lkml.kernel.org/r/1480554346-29071-11-git-send-email-zohar@linux.vnet.ibm.com
Signed-off-by: Andreas Steffen <andreas.steffen@strongswan.org>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
Cc: Josh Sklar <sklar@linux.vnet.ibm.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stewart Smith <stewart@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Andreas Steffen 2016-12-19 16:23:00 -08:00 committed by Linus Torvalds
parent d68a6fe9fc
commit 98e1d55d03
1 changed files with 4 additions and 2 deletions

View File

@ -477,11 +477,13 @@ static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data,
u8 buffer[IMA_EVENT_NAME_LEN_MAX + 1] = { 0 };
u8 *data_to_hash = field_data[i].data;
u32 datalen = field_data[i].len;
u32 datalen_to_hash =
!ima_canonical_fmt ? datalen : cpu_to_le32(datalen);
if (strcmp(td->name, IMA_TEMPLATE_IMA_NAME) != 0) {
rc = crypto_shash_update(shash,
(const u8 *) &field_data[i].len,
sizeof(field_data[i].len));
(const u8 *) &datalen_to_hash,
sizeof(datalen_to_hash));
if (rc)
break;
} else if (strcmp(td->fields[i]->field_id, "n") == 0) {