vboot2: Change preamble to contain a list of signatures
Use struct vb2_signature2 objects to hold the hashes of firmware
components, rather than a separate vb2_fw_preamble2_hash struct.
Better for code reuse.
BUG=chromium:423882
BRANCH=none
TEST=VBOOT2=1 make runtests
Change-Id: Ia9e23c1488a884f2d6fab4c4be51b25d3ff25c2f
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/228241
Reviewed-by: Daisuke Nojiri <dnojiri@chromium.org>
diff --git a/firmware/2lib/2common2.c b/firmware/2lib/2common2.c
index 813e2b6..1dcf53d 100644
--- a/firmware/2lib/2common2.c
+++ b/firmware/2lib/2common2.c
@@ -353,7 +353,7 @@
return rv;
/* Skip signature if it doesn't match the key GUID */
- if (memcmp(&sig->key_guid, key->guid, GUID_SIZE))
+ if (memcmp(&sig->guid, key->guid, GUID_SIZE))
continue;
/* Make sure we signed the right amount of data */
diff --git a/firmware/2lib/2packed_key2.c b/firmware/2lib/2packed_key2.c
index 264ca13..c009c2b 100644
--- a/firmware/2lib/2packed_key2.c
+++ b/firmware/2lib/2packed_key2.c
@@ -92,7 +92,7 @@
key->desc = "";
key->version = pkey->key_version;
- key->guid = &pkey->key_guid;
+ key->guid = &pkey->guid;
return VB2_SUCCESS;
}
diff --git a/firmware/2lib/include/2common.h b/firmware/2lib/include/2common.h
index e0b252b..0f7012c 100644
--- a/firmware/2lib/include/2common.h
+++ b/firmware/2lib/include/2common.h
@@ -299,10 +299,10 @@
enum vb2_hash_algorithm hash_alg);
/**
- * Return a key_guid for an unsigned hash algorithm.
+ * Return a key guid for an unsigned hash algorithm.
*
* @param hash_alg Hash algorithm to return key for
- * @return A pointer to the key_guid for that hash algorithm and
+ * @return A pointer to the key guid for that hash algorithm and
* sig_alg=VB2_SIG_NONE, or NULL if error.
*/
const struct vb2_guid *vb2_hash_guid(enum vb2_hash_algorithm hash_alg);
diff --git a/firmware/2lib/include/2struct.h b/firmware/2lib/include/2struct.h
index bfe2355..e988f3f 100644
--- a/firmware/2lib/include/2struct.h
+++ b/firmware/2lib/include/2struct.h
@@ -381,7 +381,7 @@
uint32_t key_version;
/* Key GUID */
- struct vb2_guid key_guid;
+ struct vb2_guid guid;
} __attribute__((packed));
#define EXPECTED_VB2_PACKED_KEY2_SIZE \
@@ -419,11 +419,17 @@
uint16_t hash_alg;
/*
- * GUID of key used to generate this signature. This allows the
- * firmware to quickly determine which signature block (if any) goes
- * with the key being used by the firmware.
+ * GUID for the signature.
+ *
+ * If this is a keyblock signature entry, this is the GUID of the key
+ * used to generate this signature. This allows the firmware to
+ * quickly determine which signature block (if any) goes with the key
+ * being used by the firmware.
+ *
+ * If this is a preamble hash entry, this is the GUID of the data type
+ * being hashed. There is no key GUID, because sig_alg=VB2_ALG_NONE.
*/
- struct vb2_guid key_guid;
+ struct vb2_guid guid;
} __attribute__((packed));
#define EXPECTED_VB2_SIGNATURE2_SIZE \
@@ -475,6 +481,9 @@
* Kernels often have at least two signatures - one using the kernel
* subkey from the RW firmware (for signed kernels) and one which is
* simply a SHA-512 hash (for unsigned developer kernels).
+ *
+ * The GUID for each signature indicates which key was used to generate
+ * the signature.
*/
uint32_t sig_offset;
} __attribute__((packed));
@@ -486,20 +495,6 @@
#define VB2_PREAMBLE2_VERSION_MAJOR 3
#define VB2_PREAMBLE2_VERSION_MINOR 0
-/* Single hash entry for the firmware preamble */
-struct vb2_fw_preamble2_hash {
- /* Type of data being hashed (enum vb2api_hash_tag) */
- uint32_t tag;
-
- /* Size of hashed data in bytes */
- uint32_t data_size;
-
- /* Hash digest follows this struct */
- uint8_t digest[0];
-} __attribute__((packed));
-
-#define EXPECTED_VB2_FW_PREAMBLE2_HASH_SIZE 8
-
/*
* Firmware preamble
*
@@ -525,34 +520,22 @@
uint32_t sig_offset;
/*
- * The preamble contains a list of hashes for the various firmware
- * components. The calling firmware is responsible for knowing where
- * to find those components, which may be on a different storage device
- * than this preamble.
+ * The preamble contains a list of hashes (struct vb2_signature2) for
+ * the various firmware components. These have sig_alg=VB2_SIG_NONE,
+ * and the GUID for each hash identifies the component being hashed.
+ * The calling firmware is responsible for knowing where to find those
+ * components, which may be on a different storage device than this
+ * preamble.
*/
/* Number of hash entries */
uint32_t hash_count;
- /*
- * Hash algorithm used (must be same for all entries) (enum
- * vb2_hash_algorithm).
- */
- uint16_t hash_alg;
-
- /* Size of each hash entry, in bytes */
- uint16_t hash_entry_size;
-
- /*
- * Offset of first hash entry from start of preamble. Entry N can be
- * found at:
- *
- * (uint8_t *)hdr + hdr->hash_table_offset + N * hdr->hash_entry_size
- */
- uint32_t hash_table_offset;
+ /* Offset of first hash entry from start of preamble */
+ uint32_t hash_offset;
} __attribute__((packed));
-#define EXPECTED_VB2_FW_PREAMBLE2_SIZE (EXPECTED_VB2_STRUCT_COMMON_SIZE + 24)
+#define EXPECTED_VB2_FW_PREAMBLE2_SIZE (EXPECTED_VB2_STRUCT_COMMON_SIZE + 20)
/****************************************************************************/
diff --git a/tests/vb2_common_tests.c b/tests/vb2_common_tests.c
index e8c7d1f..ad7635e 100644
--- a/tests/vb2_common_tests.c
+++ b/tests/vb2_common_tests.c
@@ -165,9 +165,6 @@
TEST_EQ(EXPECTED_VB2_FW_PREAMBLE2_SIZE,
sizeof(struct vb2_fw_preamble2),
"sizeof(vb2_fw_preamble2)");
- TEST_EQ(EXPECTED_VB2_FW_PREAMBLE2_HASH_SIZE,
- sizeof(struct vb2_fw_preamble2_hash),
- "sizeof(vb2_fw_preamble2_hash)");
}
/**
diff --git a/tests/vb2_convert_structs.c b/tests/vb2_convert_structs.c
index 777c738..0c4a7ec 100644
--- a/tests/vb2_convert_structs.c
+++ b/tests/vb2_convert_structs.c
@@ -84,11 +84,11 @@
if (key) {
s2.sig_alg = key->sig_alg;
s2.hash_alg = key->hash_alg;
- memcpy(&s2.key_guid, &key->key_guid, GUID_SIZE);
+ memcpy(&s2.guid, &key->guid, GUID_SIZE);
} else {
s2.sig_alg = VB2_SIG_INVALID;
s2.hash_alg = VB2_HASH_INVALID;
- memset(&s2.key_guid, 0, GUID_SIZE);
+ memset(&s2.guid, 0, GUID_SIZE);
}
/* Allocate the new buffer */
@@ -135,7 +135,7 @@
if (!hash_guid || !s.sig_size)
return NULL;
- memcpy(&s.key_guid, hash_guid, sizeof(s.key_guid));
+ memcpy(&s.guid, hash_guid, sizeof(s.guid));
s.sig_offset = s.c.fixed_size + s.c.desc_size;
s.c.total_size = s.sig_offset + s.sig_size;
