Refactor: make cryptfs.h smaller
Move most of it into cryptfs.cpp, and include cryptfs.h in fewer files.
Bug: 147814592
Test: Treehugger
Change-Id: Ia3592d73e7abc1f07a60538e0978a3033bdea7de
diff --git a/cryptfs.h b/cryptfs.h
index 692d7ee..28d1887 100644
--- a/cryptfs.h
+++ b/cryptfs.h
@@ -17,189 +17,13 @@
#ifndef ANDROID_VOLD_CRYPTFS_H
#define ANDROID_VOLD_CRYPTFS_H
-/* This structure starts 16,384 bytes before the end of a hardware
- * partition that is encrypted, or in a separate partition. It's location
- * is specified by a property set in init.<device>.rc.
- * The structure allocates 48 bytes for a key, but the real key size is
- * specified in the struct. Currently, the code is hardcoded to use 128
- * bit keys.
- * The fields after salt are only valid in rev 1.1 and later stuctures.
- * Obviously, the filesystem does not include the last 16 kbytes
- * of the partition if the crypt_mnt_ftr lives at the end of the
- * partition.
- */
-
#include <linux/types.h>
#include <stdbool.h>
#include <stdint.h>
#include <cutils/properties.h>
-/* The current cryptfs version */
-#define CURRENT_MAJOR_VERSION 1
-#define CURRENT_MINOR_VERSION 3
-
#define CRYPT_FOOTER_OFFSET 0x4000
-#define CRYPT_FOOTER_TO_PERSIST_OFFSET 0x1000
-#define CRYPT_PERSIST_DATA_SIZE 0x1000
-
-#define MAX_CRYPTO_TYPE_NAME_LEN 64
-
-#define MAX_KEY_LEN 48
-#define SALT_LEN 16
-#define SCRYPT_LEN 32
-
-/* definitions of flags in the structure below */
-#define CRYPT_MNT_KEY_UNENCRYPTED 0x1 /* The key for the partition is not encrypted. */
-#define CRYPT_ENCRYPTION_IN_PROGRESS \
- 0x2 /* Encryption partially completed, \
- encrypted_upto valid*/
-#define CRYPT_INCONSISTENT_STATE \
- 0x4 /* Set when starting encryption, clear when \
- exit cleanly, either through success or \
- correctly marked partial encryption */
-#define CRYPT_DATA_CORRUPT \
- 0x8 /* Set when encryption is fine, but the \
- underlying volume is corrupt */
-#define CRYPT_FORCE_ENCRYPTION \
- 0x10 /* Set when it is time to encrypt this \
- volume on boot. Everything in this \
- structure is set up correctly as \
- though device is encrypted except \
- that the master key is encrypted with the \
- default password. */
-#define CRYPT_FORCE_COMPLETE \
- 0x20 /* Set when the above encryption cycle is \
- complete. On next cryptkeeper entry, match \
- the password. If it matches fix the master \
- key and remove this flag. */
-
-/* Allowed values for type in the structure below */
-#define CRYPT_TYPE_PASSWORD \
- 0 /* master_key is encrypted with a password \
- * Must be zero to be compatible with pre-L \
- * devices where type is always password.*/
-#define CRYPT_TYPE_DEFAULT \
- 1 /* master_key is encrypted with default \
- * password */
-#define CRYPT_TYPE_PATTERN 2 /* master_key is encrypted with a pattern */
-#define CRYPT_TYPE_PIN 3 /* master_key is encrypted with a pin */
-#define CRYPT_TYPE_MAX_TYPE 3 /* type cannot be larger than this value */
-
-#define CRYPT_MNT_MAGIC 0xD0B5B1C4
-#define PERSIST_DATA_MAGIC 0xE950CD44
-
-/* Key Derivation Function algorithms */
-#define KDF_PBKDF2 1
-#define KDF_SCRYPT 2
-/* Algorithms 3 & 4 deprecated before shipping outside of google, so removed */
-#define KDF_SCRYPT_KEYMASTER 5
-
-/* Maximum allowed keymaster blob size. */
-#define KEYMASTER_BLOB_SIZE 2048
-
-/* __le32 and __le16 defined in system/extras/ext4_utils/ext4_utils.h */
-#define __le8 unsigned char
-
-#if !defined(SHA256_DIGEST_LENGTH)
-#define SHA256_DIGEST_LENGTH 32
-#endif
-
-struct crypt_mnt_ftr {
- __le32 magic; /* See above */
- __le16 major_version;
- __le16 minor_version;
- __le32 ftr_size; /* in bytes, not including key following */
- __le32 flags; /* See above */
- __le32 keysize; /* in bytes */
- __le32 crypt_type; /* how master_key is encrypted. Must be a
- * CRYPT_TYPE_XXX value */
- __le64 fs_size; /* Size of the encrypted fs, in 512 byte sectors */
- __le32 failed_decrypt_count; /* count of # of failed attempts to decrypt and
- mount, set to 0 on successful mount */
- unsigned char crypto_type_name[MAX_CRYPTO_TYPE_NAME_LEN]; /* The type of encryption
- needed to decrypt this
- partition, null terminated */
- __le32 spare2; /* ignored */
- unsigned char master_key[MAX_KEY_LEN]; /* The encrypted key for decrypting the filesystem */
- unsigned char salt[SALT_LEN]; /* The salt used for this encryption */
- __le64 persist_data_offset[2]; /* Absolute offset to both copies of crypt_persist_data
- * on device with that info, either the footer of the
- * real_blkdevice or the metadata partition. */
-
- __le32 persist_data_size; /* The number of bytes allocated to each copy of the
- * persistent data table*/
-
- __le8 kdf_type; /* The key derivation function used. */
-
- /* scrypt parameters. See www.tarsnap.com/scrypt/scrypt.pdf */
- __le8 N_factor; /* (1 << N) */
- __le8 r_factor; /* (1 << r) */
- __le8 p_factor; /* (1 << p) */
- __le64 encrypted_upto; /* If we are in state CRYPT_ENCRYPTION_IN_PROGRESS and
- we have to stop (e.g. power low) this is the last
- encrypted 512 byte sector.*/
- __le8 hash_first_block[SHA256_DIGEST_LENGTH]; /* When CRYPT_ENCRYPTION_IN_PROGRESS
- set, hash of first block, used
- to validate before continuing*/
-
- /* key_master key, used to sign the derived key which is then used to generate
- * the intermediate key
- * This key should be used for no other purposes! We use this key to sign unpadded
- * data, which is acceptable but only if the key is not reused elsewhere. */
- __le8 keymaster_blob[KEYMASTER_BLOB_SIZE];
- __le32 keymaster_blob_size;
-
- /* Store scrypt of salted intermediate key. When decryption fails, we can
- check if this matches, and if it does, we know that the problem is with the
- drive, and there is no point in asking the user for more passwords.
-
- Note that if any part of this structure is corrupt, this will not match and
- we will continue to believe the user entered the wrong password. In that
- case the only solution is for the user to enter a password enough times to
- force a wipe.
-
- Note also that there is no need to worry about migration. If this data is
- wrong, we simply won't recognise a right password, and will continue to
- prompt. On the first password change, this value will be populated and
- then we will be OK.
- */
- unsigned char scrypted_intermediate_key[SCRYPT_LEN];
-
- /* sha of this structure with this element set to zero
- Used when encrypting on reboot to validate structure before doing something
- fatal
- */
- unsigned char sha256[SHA256_DIGEST_LENGTH];
-};
-
-/* Persistant data that should be available before decryption.
- * Things like airplane mode, locale and timezone are kept
- * here and can be retrieved by the CryptKeeper UI to properly
- * configure the phone before asking for the password
- * This is only valid if the major and minor version above
- * is set to 1.1 or higher.
- *
- * This is a 4K structure. There are 2 copies, and the code alternates
- * writing one and then clearing the previous one. The reading
- * code reads the first valid copy it finds, based on the magic number.
- * The absolute offset to the first of the two copies is kept in rev 1.1
- * and higher crypt_mnt_ftr structures.
- */
-struct crypt_persist_entry {
- char key[PROPERTY_KEY_MAX];
- char val[PROPERTY_VALUE_MAX];
-};
-
-/* Should be exactly 4K in size */
-struct crypt_persist_data {
- __le32 persist_magic;
- __le32 persist_valid_entries;
- __le32 persist_spare[30];
- struct crypt_persist_entry persist_entry[0];
-};
-
-#define DATA_MNT_POINT "/data"
/* Return values for cryptfs_crypto_complete */
#define CRYPTO_COMPLETE_NOT_ENCRYPTED 1
@@ -209,11 +33,6 @@
#define CRYPTO_COMPLETE_INCONSISTENT (-3)
#define CRYPTO_COMPLETE_CORRUPT (-4)
-/* Return values for cryptfs_enable_inplace*() */
-#define ENABLE_INPLACE_OK 0
-#define ENABLE_INPLACE_ERR_OTHER (-1)
-#define ENABLE_INPLACE_ERR_DEV (-2) /* crypto_blkdev issue */
-
/* Return values for cryptfs_getfield */
#define CRYPTO_GETFIELD_OK 0
#define CRYPTO_GETFIELD_ERROR_NO_FIELD (-1)
@@ -231,11 +50,8 @@
#define PERSIST_DEL_KEY_ERROR_OTHER (-1)
#define PERSIST_DEL_KEY_ERROR_NO_FIELD (-2)
+// Exposed for testing only
int match_multi_entry(const char* key, const char* field, unsigned index);
-int wait_and_unmount(const char* mountpoint, bool kill);
-
-typedef int (*kdf_func)(const char* passwd, const unsigned char* salt, unsigned char* ikey,
- void* params);
int cryptfs_crypto_complete(void);
int cryptfs_check_passwd(const char* pw);