1 files changed, 231 insertions, 0 deletions

diff --git a/crypto/lollipop/cryptfs.h b/crypto/lollipop/cryptfs.h
new file mode 100644
index 000000000..b95a290cf
--- /dev/null
+++ b/crypto/lollipop/cryptfs.h
@@ -0,0 +1,231 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* 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 <cutils/properties.h>
+#include "openssl/sha.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 */
+
+/* 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
+
+#define SCRYPT_PROP "ro.crypto.scrypt_params"
+#define SCRYPT_DEFAULTS { 15, 3, 1 }
+
+/* Key Derivation Function algorithms */
+#define KDF_PBKDF2 1
+#define KDF_SCRYPT 2
+/* TODO(paullawrence): Remove KDF_SCRYPT_KEYMASTER_UNPADDED and KDF_SCRYPT_KEYMASTER_BADLY_PADDED
+ * when it is safe to do so. */
+#define KDF_SCRYPT_KEYMASTER_UNPADDED 3
+#define KDF_SCRYPT_KEYMASTER_BADLY_PADDED 4
+#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
+
+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];
+};
+
+/* 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];
+};
+
+struct volume_info {
+   unsigned int size;
+   unsigned int flags;
+   struct crypt_mnt_ftr crypt_ftr;
+   char mnt_point[256];
+   char blk_dev[256];
+   char crypto_blkdev[256];
+   char label[256];
+};
+#define VOL_NONREMOVABLE   0x1
+#define VOL_ENCRYPTABLE    0x2
+#define VOL_PRIMARY        0x4
+#define VOL_PROVIDES_ASEC  0x8
+
+#define DATA_MNT_POINT "/data"
+
+/* Return values for cryptfs_crypto_complete */
+#define CRYPTO_COMPLETE_NOT_ENCRYPTED  1
+#define CRYPTO_COMPLETE_ENCRYPTED      0
+#define CRYPTO_COMPLETE_BAD_METADATA  -1
+#define CRYPTO_COMPLETE_PARTIAL       -2
+#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 */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+  typedef int (*kdf_func)(const char *passwd, const unsigned char *salt,
+                          unsigned char *ikey, void *params);
+
+  int cryptfs_crypto_complete(void);
+  int cryptfs_check_footer(void);
+  int cryptfs_check_passwd(char *pw);
+  int cryptfs_verify_passwd(char *newpw);
+  int cryptfs_restart(void);
+  int cryptfs_enable(char *flag, int type, char *passwd, int allow_reboot);
+  int cryptfs_changepw(int type, const char *newpw);
+  int cryptfs_enable_default(char *flag, int allow_reboot);
+  int cryptfs_setup_volume(const char *label, int major, int minor,
+                           char *crypto_dev_path, unsigned int max_pathlen,
+                           int *new_major, int *new_minor);
+  int cryptfs_revert_volume(const char *label);
+  int cryptfs_getfield(char *fieldname, char *value, int len);
+  int cryptfs_setfield(char *fieldname, char *value);
+  int cryptfs_mount_default_encrypted(void);
+  int cryptfs_get_password_type(void);
+  char* cryptfs_get_password(void);
+  void cryptfs_clear_password(void);
+#ifdef __cplusplus
+}
+#endif