From bc3089313e9dfd3eb4af98cb347d96d368458ead Mon Sep 17 00:00:00 2001
From: Sarthak Kukreti <sarthakkukreti@google.com>
Date: Wed, 24 Jun 2020 14:50:34 -0700
Subject: [PATCH] CHROMIUM: Add fscrypt header

Add fscrypt header from 5.4 to build userspace utilities with
fscrypt. Move redundant definitions to use fscrypt.h instead.

Signed-off-by: Sarthak Kukreti <sarthakkukreti@google.com>
---
 include/uapi/linux/fs.h      |  48 +--------
 include/uapi/linux/fscrypt.h | 182 +++++++++++++++++++++++++++++++++++
 2 files changed, 183 insertions(+), 47 deletions(-)
 create mode 100644 include/uapi/linux/fscrypt.h

diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h
index 4199f8a..f2c910d 100644
--- a/include/uapi/linux/fs.h
+++ b/include/uapi/linux/fs.h
@@ -13,6 +13,7 @@
 #include <linux/limits.h>
 #include <linux/ioctl.h>
 #include <linux/types.h>
+#include <linux/fscrypt.h>
 
 /*
  * It's silly to have NR_OPEN bigger than NR_FILE, but you can change
@@ -254,53 +255,6 @@ struct fsxattr {
 #define FS_IOC_FSGETXATTR		_IOR ('X', 31, struct fsxattr)
 #define FS_IOC_FSSETXATTR		_IOW ('X', 32, struct fsxattr)
 
-/*
- * File system encryption support
- */
-/* Policy provided via an ioctl on the topmost directory */
-#define FS_KEY_DESCRIPTOR_SIZE	8
-
-#define FS_POLICY_FLAGS_PAD_4		0x00
-#define FS_POLICY_FLAGS_PAD_8		0x01
-#define FS_POLICY_FLAGS_PAD_16		0x02
-#define FS_POLICY_FLAGS_PAD_32		0x03
-#define FS_POLICY_FLAGS_PAD_MASK	0x03
-#define FS_POLICY_FLAGS_VALID		0x03
-
-/* Encryption algorithms */
-#define FS_ENCRYPTION_MODE_INVALID		0
-#define FS_ENCRYPTION_MODE_AES_256_XTS		1
-#define FS_ENCRYPTION_MODE_AES_256_GCM		2
-#define FS_ENCRYPTION_MODE_AES_256_CBC		3
-#define FS_ENCRYPTION_MODE_AES_256_CTS		4
-#define FS_ENCRYPTION_MODE_AES_128_CBC		5
-#define FS_ENCRYPTION_MODE_AES_128_CTS		6
-
-struct fscrypt_policy {
-	__u8 version;
-	__u8 contents_encryption_mode;
-	__u8 filenames_encryption_mode;
-	__u8 flags;
-	__u8 master_key_descriptor[FS_KEY_DESCRIPTOR_SIZE];
-};
-
-#define FS_IOC_SET_ENCRYPTION_POLICY	_IOR('f', 19, struct fscrypt_policy)
-#define FS_IOC_GET_ENCRYPTION_PWSALT	_IOW('f', 20, __u8[16])
-#define FS_IOC_GET_ENCRYPTION_POLICY	_IOW('f', 21, struct fscrypt_policy)
-
-/* Parameters for passing an encryption key into the kernel keyring */
-#define FS_KEY_DESC_PREFIX		"fscrypt:"
-#define FS_KEY_DESC_PREFIX_SIZE		8
-
-/* Structure that userspace passes to the kernel keyring */
-#define FS_MAX_KEY_SIZE			64
-
-struct fscrypt_key {
-	__u32 mode;
-	__u8 raw[FS_MAX_KEY_SIZE];
-	__u32 size;
-};
-
 /*
  * Inode flags (FS_IOC_GETFLAGS / FS_IOC_SETFLAGS)
  *
diff --git a/include/uapi/linux/fscrypt.h b/include/uapi/linux/fscrypt.h
new file mode 100644
index 0000000..1beb174
--- /dev/null
+++ b/include/uapi/linux/fscrypt.h
@@ -0,0 +1,182 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * fscrypt user API
+ *
+ * These ioctls can be used on filesystems that support fscrypt.  See the
+ * "User API" section of Documentation/filesystems/fscrypt.rst.
+ */
+#ifndef _UAPI_LINUX_FSCRYPT_H
+#define _UAPI_LINUX_FSCRYPT_H
+
+#include <linux/types.h>
+
+/* Encryption policy flags */
+#define FSCRYPT_POLICY_FLAGS_PAD_4		0x00
+#define FSCRYPT_POLICY_FLAGS_PAD_8		0x01
+#define FSCRYPT_POLICY_FLAGS_PAD_16		0x02
+#define FSCRYPT_POLICY_FLAGS_PAD_32		0x03
+#define FSCRYPT_POLICY_FLAGS_PAD_MASK		0x03
+#define FSCRYPT_POLICY_FLAG_DIRECT_KEY		0x04
+#define FSCRYPT_POLICY_FLAG_IV_INO_LBLK_64	0x08
+#define FSCRYPT_POLICY_FLAGS_VALID		0x0F
+
+/* Encryption algorithms */
+#define FSCRYPT_MODE_AES_256_XTS		1
+#define FSCRYPT_MODE_AES_256_CTS		4
+#define FSCRYPT_MODE_AES_128_CBC		5
+#define FSCRYPT_MODE_AES_128_CTS		6
+#define FSCRYPT_MODE_ADIANTUM			9
+#define __FSCRYPT_MODE_MAX			9
+
+/*
+ * Legacy policy version; ad-hoc KDF and no key verification.
+ * For new encrypted directories, use fscrypt_policy_v2 instead.
+ *
+ * Careful: the .version field for this is actually 0, not 1.
+ */
+#define FSCRYPT_POLICY_V1		0
+#define FSCRYPT_KEY_DESCRIPTOR_SIZE	8
+struct fscrypt_policy_v1 {
+	__u8 version;
+	__u8 contents_encryption_mode;
+	__u8 filenames_encryption_mode;
+	__u8 flags;
+	__u8 master_key_descriptor[FSCRYPT_KEY_DESCRIPTOR_SIZE];
+};
+#define fscrypt_policy	fscrypt_policy_v1
+
+/*
+ * Process-subscribed "logon" key description prefix and payload format.
+ * Deprecated; prefer FS_IOC_ADD_ENCRYPTION_KEY instead.
+ */
+#define FSCRYPT_KEY_DESC_PREFIX		"fscrypt:"
+#define FSCRYPT_KEY_DESC_PREFIX_SIZE	8
+#define FSCRYPT_MAX_KEY_SIZE		64
+struct fscrypt_key {
+	__u32 mode;
+	__u8 raw[FSCRYPT_MAX_KEY_SIZE];
+	__u32 size;
+};
+
+/*
+ * New policy version with HKDF and key verification (recommended).
+ */
+#define FSCRYPT_POLICY_V2		2
+#define FSCRYPT_KEY_IDENTIFIER_SIZE	16
+struct fscrypt_policy_v2 {
+	__u8 version;
+	__u8 contents_encryption_mode;
+	__u8 filenames_encryption_mode;
+	__u8 flags;
+	__u8 __reserved[4];
+	__u8 master_key_identifier[FSCRYPT_KEY_IDENTIFIER_SIZE];
+};
+
+/* Struct passed to FS_IOC_GET_ENCRYPTION_POLICY_EX */
+struct fscrypt_get_policy_ex_arg {
+	__u64 policy_size; /* input/output */
+	union {
+		__u8 version;
+		struct fscrypt_policy_v1 v1;
+		struct fscrypt_policy_v2 v2;
+	} policy; /* output */
+};
+
+/*
+ * v1 policy keys are specified by an arbitrary 8-byte key "descriptor",
+ * matching fscrypt_policy_v1::master_key_descriptor.
+ */
+#define FSCRYPT_KEY_SPEC_TYPE_DESCRIPTOR	1
+
+/*
+ * v2 policy keys are specified by a 16-byte key "identifier" which the kernel
+ * calculates as a cryptographic hash of the key itself,
+ * matching fscrypt_policy_v2::master_key_identifier.
+ */
+#define FSCRYPT_KEY_SPEC_TYPE_IDENTIFIER	2
+
+/*
+ * Specifies a key, either for v1 or v2 policies.  This doesn't contain the
+ * actual key itself; this is just the "name" of the key.
+ */
+struct fscrypt_key_specifier {
+	__u32 type;	/* one of FSCRYPT_KEY_SPEC_TYPE_* */
+	__u32 __reserved;
+	union {
+		__u8 __reserved[32]; /* reserve some extra space */
+		__u8 descriptor[FSCRYPT_KEY_DESCRIPTOR_SIZE];
+		__u8 identifier[FSCRYPT_KEY_IDENTIFIER_SIZE];
+	} u;
+};
+
+/* Struct passed to FS_IOC_ADD_ENCRYPTION_KEY */
+struct fscrypt_add_key_arg {
+	struct fscrypt_key_specifier key_spec;
+	__u32 raw_size;
+	__u32 __reserved[9];
+	__u8 raw[];
+};
+
+/* Struct passed to FS_IOC_REMOVE_ENCRYPTION_KEY */
+struct fscrypt_remove_key_arg {
+	struct fscrypt_key_specifier key_spec;
+#define FSCRYPT_KEY_REMOVAL_STATUS_FLAG_FILES_BUSY	0x00000001
+#define FSCRYPT_KEY_REMOVAL_STATUS_FLAG_OTHER_USERS	0x00000002
+	__u32 removal_status_flags;	/* output */
+	__u32 __reserved[5];
+};
+
+/* Struct passed to FS_IOC_GET_ENCRYPTION_KEY_STATUS */
+struct fscrypt_get_key_status_arg {
+	/* input */
+	struct fscrypt_key_specifier key_spec;
+	__u32 __reserved[6];
+
+	/* output */
+#define FSCRYPT_KEY_STATUS_ABSENT		1
+#define FSCRYPT_KEY_STATUS_PRESENT		2
+#define FSCRYPT_KEY_STATUS_INCOMPLETELY_REMOVED	3
+	__u32 status;
+#define FSCRYPT_KEY_STATUS_FLAG_ADDED_BY_SELF   0x00000001
+	__u32 status_flags;
+	__u32 user_count;
+	__u32 __out_reserved[13];
+};
+
+#define FS_IOC_SET_ENCRYPTION_POLICY		_IOR('f', 19, struct fscrypt_policy)
+#define FS_IOC_GET_ENCRYPTION_PWSALT		_IOW('f', 20, __u8[16])
+#define FS_IOC_GET_ENCRYPTION_POLICY		_IOW('f', 21, struct fscrypt_policy)
+#define FS_IOC_GET_ENCRYPTION_POLICY_EX		_IOWR('f', 22, __u8[9]) /* size + version */
+#define FS_IOC_ADD_ENCRYPTION_KEY		_IOWR('f', 23, struct fscrypt_add_key_arg)
+#define FS_IOC_REMOVE_ENCRYPTION_KEY		_IOWR('f', 24, struct fscrypt_remove_key_arg)
+#define FS_IOC_REMOVE_ENCRYPTION_KEY_ALL_USERS	_IOWR('f', 25, struct fscrypt_remove_key_arg)
+#define FS_IOC_GET_ENCRYPTION_KEY_STATUS	_IOWR('f', 26, struct fscrypt_get_key_status_arg)
+
+/**********************************************************************/
+
+/* old names; don't add anything new here! */
+#ifndef __KERNEL__
+#define FS_KEY_DESCRIPTOR_SIZE		FSCRYPT_KEY_DESCRIPTOR_SIZE
+#define FS_POLICY_FLAGS_PAD_4		FSCRYPT_POLICY_FLAGS_PAD_4
+#define FS_POLICY_FLAGS_PAD_8		FSCRYPT_POLICY_FLAGS_PAD_8
+#define FS_POLICY_FLAGS_PAD_16		FSCRYPT_POLICY_FLAGS_PAD_16
+#define FS_POLICY_FLAGS_PAD_32		FSCRYPT_POLICY_FLAGS_PAD_32
+#define FS_POLICY_FLAGS_PAD_MASK	FSCRYPT_POLICY_FLAGS_PAD_MASK
+#define FS_POLICY_FLAG_DIRECT_KEY	FSCRYPT_POLICY_FLAG_DIRECT_KEY
+#define FS_POLICY_FLAGS_VALID		FSCRYPT_POLICY_FLAGS_VALID
+#define FS_ENCRYPTION_MODE_INVALID	0	/* never used */
+#define FS_ENCRYPTION_MODE_AES_256_XTS	FSCRYPT_MODE_AES_256_XTS
+#define FS_ENCRYPTION_MODE_AES_256_GCM	2	/* never used */
+#define FS_ENCRYPTION_MODE_AES_256_CBC	3	/* never used */
+#define FS_ENCRYPTION_MODE_AES_256_CTS	FSCRYPT_MODE_AES_256_CTS
+#define FS_ENCRYPTION_MODE_AES_128_CBC	FSCRYPT_MODE_AES_128_CBC
+#define FS_ENCRYPTION_MODE_AES_128_CTS	FSCRYPT_MODE_AES_128_CTS
+#define FS_ENCRYPTION_MODE_SPECK128_256_XTS	7	/* removed */
+#define FS_ENCRYPTION_MODE_SPECK128_256_CTS	8	/* removed */
+#define FS_ENCRYPTION_MODE_ADIANTUM	FSCRYPT_MODE_ADIANTUM
+#define FS_KEY_DESC_PREFIX		FSCRYPT_KEY_DESC_PREFIX
+#define FS_KEY_DESC_PREFIX_SIZE		FSCRYPT_KEY_DESC_PREFIX_SIZE
+#define FS_MAX_KEY_SIZE			FSCRYPT_MAX_KEY_SIZE
+#endif /* !__KERNEL__ */
+
+#endif /* _UAPI_LINUX_FSCRYPT_H */
-- 
2.26.2