Messages in this thread | | | Date | Sun, 10 Feb 2019 21:05:29 +0100 (CET) | From | David Kozub <> | Subject | Re: [PATCH v4 13/16] block: sed-opal: check size of shadow mbr |
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On Fri, 8 Feb 2019, Derrick, Jonathan wrote:
> On Fri, 2019-02-01 at 21:50 +0100, David Kozub wrote: >> From: Jonas Rabenstein <jonas.rabenstein@studium.uni-erlangen.de> >> >> Check whether the shadow mbr does fit in the provided space on the >> target. Also a proper firmware should handle this case and return an >> error we may prevent problems or even damage with crappy firmwares. >> >> Signed-off-by: Jonas Rabenstein <jonas.rabenstein@studium.uni-erlangen.de> >> Reviewed-by: Scott Bauer <sbauer@plzdonthack.me> >> --- >> block/opal_proto.h | 16 ++++++++++++++++ >> block/sed-opal.c | 39 +++++++++++++++++++++++++++++++++++++++ >> 2 files changed, 55 insertions(+) >> >> diff --git a/block/opal_proto.h b/block/opal_proto.h >> index b6e352cfe982..5e8df3245eb0 100644 >> --- a/block/opal_proto.h >> +++ b/block/opal_proto.h >> @@ -106,6 +106,7 @@ enum opal_uid { >> OPAL_ENTERPRISE_BANDMASTER0_UID, >> OPAL_ENTERPRISE_ERASEMASTER_UID, >> /* tables */ >> + OPAL_TABLE_TABLE, >> OPAL_LOCKINGRANGE_GLOBAL, >> OPAL_LOCKINGRANGE_ACE_RDLOCKED, >> OPAL_LOCKINGRANGE_ACE_WRLOCKED, >> @@ -160,6 +161,21 @@ enum opal_token { >> OPAL_STARTCOLUMN = 0x03, >> OPAL_ENDCOLUMN = 0x04, >> OPAL_VALUES = 0x01, >> + /* table table */ >> + OPAL_TABLE_UID = 0x00, >> + OPAL_TABLE_NAME = 0x01, >> + OPAL_TABLE_COMMON = 0x02, >> + OPAL_TABLE_TEMPLATE = 0x03, >> + OPAL_TABLE_KIND = 0x04, >> + OPAL_TABLE_COLUMN = 0x05, >> + OPAL_TABLE_COLUMNS = 0x06, >> + OPAL_TABLE_ROWS = 0x07, >> + OPAL_TABLE_ROWS_FREE = 0x08, >> + OPAL_TABLE_ROW_BYTES = 0x09, >> + OPAL_TABLE_LASTID = 0x0A, >> + OPAL_TABLE_MIN = 0x0B, >> + OPAL_TABLE_MAX = 0x0C, >> + >> /* authority table */ >> OPAL_PIN = 0x03, >> /* locking tokens */ >> diff --git a/block/sed-opal.c b/block/sed-opal.c >> index 2459ac4d523b..3493bb979978 100644 >> --- a/block/sed-opal.c >> +++ b/block/sed-opal.c >> @@ -139,6 +139,8 @@ static const u8 opaluid[][OPAL_UID_LENGTH] = { >> >> /* tables */ >> >> + [OPAL_TABLE_TABLE] >> + { 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x01 }, >> [OPAL_LOCKINGRANGE_GLOBAL] = >> { 0x00, 0x00, 0x08, 0x02, 0x00, 0x00, 0x00, 0x01 }, >> [OPAL_LOCKINGRANGE_ACE_RDLOCKED] = >> @@ -1120,6 +1122,29 @@ static int generic_get_column(struct opal_dev *dev, const u8 *table, >> return finalize_and_send(dev, parse_and_check_status); >> } >> >> +/* >> + * see TCG SAS 5.3.2.3 for a description of the available columns >> + * >> + * the result is provided in dev->resp->tok[4] >> + */ >> +static int generic_get_table_info(struct opal_dev *dev, enum opal_uid table, >> + u64 column) >> +{ >> + u8 uid[OPAL_UID_LENGTH]; >> + const unsigned int half = OPAL_UID_LENGTH/2; >> + >> + /* sed-opal UIDs can be split in two halves: >> + * first: actual table index >> + * second: relative index in the table >> + * so we have to get the first half of the OPAL_TABLE_TABLE and use the >> + * first part of the target table as relative index into that table >> + */ >> + memcpy(uid, opaluid[OPAL_TABLE_TABLE], half); >> + memcpy(uid+half, opaluid[table], half); >> + >> + return generic_get_column(dev, uid, column); >> +} >> + >> static int gen_key(struct opal_dev *dev, void *data) >> { >> u8 uid[OPAL_UID_LENGTH]; >> @@ -1535,6 +1560,20 @@ static int write_shadow_mbr(struct opal_dev *dev, void *data) >> u64 len; >> int err = 0; >> >> + /* do we fit in the available shadow mbr space? */ >> + err = generic_get_table_info(dev, OPAL_MBR, OPAL_TABLE_ROWS); > Wouldn't you need to multiply this by result from OPAL_TABLE_ROWBYTES? > What does ROWBYTES return for you?
Hi Jon,
reading the spec[1], I think it defines the MBR table to be a "byte table" (see 5.7.2.6 MBR (Byte Table)). For byte tables, it says (see 3.2.5.1 Kinds of Tables) "A byte table has one unnamed column of type bytes_1." I think this implies that each row is 1 byte and so number of rows = size of table in rows.
When I actually try to get OPAL_TABLE_ROWS abd OPAL_TABLE_ROWBYTES of the MBR table from a Samsung 840 EVO, I get: * OPAL_TABLE_ROWS 134217728 which is 128 MiB * OPAL_TABLE_ROWBYTES 0
I'm not sure if I'm doing something wrong here. I just added:
err = generic_get_table_info(dev, OPAL_MBR, OPAL_TABLE_ROW_BYTES); if (err) { pr_debug("MBR: could not get shadow row bytes size\n"); return err; }
row_bytes = response_get_u64(&dev->parsed, 4);
Best regards, David
[1] https://trustedcomputinggroup.org/wp-content/uploads/TCG_Storage_Architecture_Core_Spec_v2.01_r1.00.pdf
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