ANDROID: Incremental fs: Remove signature checks from kernel

Test: selftests pass
Bug: 133435829
Signed-off-by: Paul Lawrence <paullawrence@google.com>
Change-Id: Ia7e69b1b0176202da4b418ea815b370cbdacd5c2

1 files changed, 24 insertions, 45 deletions

diff --git a/include/uapi/linux/incrementalfs.h b/include/uapi/linux/incrementalfs.h
index 81947ded482e..2efc53f591ef 100644
--- a/include/uapi/linux/incrementalfs.h
+++ b/include/uapi/linux/incrementalfs.h
@@ -35,6 +35,8 @@
 #define INCFS_XATTR_METADATA_NAME (XATTR_USER_PREFIX "incfs.metadata")
 
 #define INCFS_MAX_SIGNATURE_SIZE 8096
+#define INCFS_SIGNATURE_VERSION 2
+#define INCFS_SIGNATURE_SECTIONS 2
 
 #define INCFS_IOCTL_BASE_CODE 'g'
 
@@ -142,48 +144,6 @@ enum incfs_hash_tree_algorithm {
 	INCFS_HASH_TREE_SHA256 = 1
 };
 
-struct incfs_file_signature_info {
-	/*
-	 * A pointer to file's root hash (if determined != 0)
-	 * Actual hash size determined by hash_tree_alg.
-	 * Size of the buffer should be at least INCFS_MAX_HASH_SIZE
-	 *
-	 * Equivalent to: u8 *root_hash;
-	 */
-	__aligned_u64 root_hash;
-
-	/*
-	 * A pointer to additional data that was attached to the root hash
-	 * before signing.
-	 *
-	 * Equivalent to: u8 *additional_data;
-	 */
-	__aligned_u64 additional_data;
-
-	/* Size of additional data. */
-	__u32 additional_data_size;
-
-	/* Reserved - must be 0 */
-	__u32 reserved1;
-
-	/*
-	 * A pointer to pkcs7 signature DER blob.
-	 *
-	 * Equivalent to: u8 *signature;
-	 */
-	__aligned_u64 signature;
-
-
-	/* Size of pkcs7 signature DER blob */
-	__u32 signature_size;
-
-	/* Reserved - must be 0 */
-	__u32 reserved2;
-
-	/* Value from incfs_hash_tree_algorithm */
-	__u8 hash_tree_alg;
-};
-
 /*
  * Create a new file or directory.
  */
@@ -240,11 +200,30 @@ struct incfs_new_file_args {
 	/* Reserved - must be 0 */
 	__u32 reserved4;
 
-	/* struct incfs_file_signature_info *signature_info; */
+	/*
+	 * Points to an APK V4 Signature data blob
+	 * Signature must have two sections
+	 * Format is:
+	 *	u32 version
+	 *	u32 size_of_hash_info_section
+	 *	u8 hash_info_section[]
+	 *	u32 size_of_signing_info_section
+	 *	u8 signing_info_section[]
+	 *
+	 * Note that incfs does not care about what is in signing_info_section
+	 *
+	 * hash_info_section has following format:
+	 *	u32 hash_algorithm; // Must be SHA256 == 1
+	 *	u8 log2_blocksize;  // Must be 12 for 4096 byte blocks
+	 *	u32 salt_size;
+	 *	u8 salt[];
+	 *	u32 hash_size;
+	 *	u8 root_hash[];
+	 */
 	__aligned_u64 signature_info;
 
-	/* Reserved - must be 0 */
-	__aligned_u64 reserved5;
+	/* Size of signature_info */
+	__aligned_u64 signature_size;
 
 	/* Reserved - must be 0 */
 	__aligned_u64 reserved6;