From 71413f4ee9a2d345da059793e795d798924b2209 Mon Sep 17 00:00:00 2001 From: Ethan Yonker Date: Wed, 26 Feb 2014 13:36:08 -0600 Subject: Check crypto footer before offering to decrypt Verify that we have a valid footer with proper magic before setting things up for decryption to help prevent user confusion when dealing with data partitions that fail to mount. Also check to make sure that the block device for /data is present. Change-Id: Ie87818fe4505a8bf71df7d3934c114e7328ef3ca --- crypto/ics/cryptfs.c | 22 ++++++++++++++++++++++ crypto/ics/cryptfs.h | 1 + crypto/jb/cryptfs.c | 23 +++++++++++++++++++++-- crypto/jb/cryptfs.h | 1 + partition.cpp | 48 ++++++++++++++++++++++++++++++++++++++++-------- partitionmanager.cpp | 6 +++--- 6 files changed, 88 insertions(+), 13 deletions(-) diff --git a/crypto/ics/cryptfs.c b/crypto/ics/cryptfs.c index 193339ec9..4f3d5d01a 100644 --- a/crypto/ics/cryptfs.c +++ b/crypto/ics/cryptfs.c @@ -653,6 +653,28 @@ int cryptfs_crypto_complete(void) return -1; } +int cryptfs_check_footer(void) +{ + int rc = -1; + char fs_type[PROPERTY_VALUE_MAX]; + char real_blkdev[MAXPATHLEN]; + char fs_options[PROPERTY_VALUE_MAX]; + unsigned long mnt_flags; + struct crypt_mnt_ftr crypt_ftr; + /* Allocate enough space for a 256 bit key, but we may use less */ + unsigned char encrypted_master_key[256]; + unsigned char salt[SALT_LEN]; + + if (get_orig_mount_parms(DATA_MNT_POINT, fs_type, real_blkdev, &mnt_flags, fs_options)) { + printf("Error reading original mount parms for mount point %s\n", DATA_MNT_POINT); + return rc; + } + + rc = get_crypt_ftr_and_key(real_blkdev, &crypt_ftr, encrypted_master_key, salt); + + return rc; +} + int cryptfs_check_passwd(const char *passwd) { char pwbuf[256]; diff --git a/crypto/ics/cryptfs.h b/crypto/ics/cryptfs.h index eee43b3bc..8c8037659 100644 --- a/crypto/ics/cryptfs.h +++ b/crypto/ics/cryptfs.h @@ -76,6 +76,7 @@ struct crypt_mnt_ftr { #ifdef __cplusplus extern "C" { #endif + int cryptfs_check_footer(void); int cryptfs_check_passwd(const char *pw); #ifdef __cplusplus } diff --git a/crypto/jb/cryptfs.c b/crypto/jb/cryptfs.c index 4e5706b64..f9c0d7489 100644 --- a/crypto/jb/cryptfs.c +++ b/crypto/jb/cryptfs.c @@ -1354,13 +1354,32 @@ int cryptfs_crypto_complete(void) #define FSTAB_PREFIX "/fstab." +int cryptfs_check_footer(void) +{ + int rc = -1; + char fstab_filename[PROPERTY_VALUE_MAX + sizeof(FSTAB_PREFIX)]; + char propbuf[PROPERTY_VALUE_MAX]; + struct crypt_mnt_ftr crypt_ftr; + + property_get("ro.hardware", propbuf, ""); + snprintf(fstab_filename, sizeof(fstab_filename), FSTAB_PREFIX"%s", propbuf); + + fstab = fs_mgr_read_fstab(fstab_filename); + if (!fstab) { + printf("failed to open %s\n", fstab_filename); + return -1; + } + + rc = get_crypt_ftr_and_key(&crypt_ftr); + + return rc; +} + int cryptfs_check_passwd(char *passwd) { int rc = -1; char fstab_filename[PROPERTY_VALUE_MAX + sizeof(FSTAB_PREFIX)]; char propbuf[PROPERTY_VALUE_MAX]; - int i; - int flags; property_get("ro.hardware", propbuf, ""); snprintf(fstab_filename, sizeof(fstab_filename), FSTAB_PREFIX"%s", propbuf); diff --git a/crypto/jb/cryptfs.h b/crypto/jb/cryptfs.h index 162159eb0..d815814d3 100644 --- a/crypto/jb/cryptfs.h +++ b/crypto/jb/cryptfs.h @@ -139,6 +139,7 @@ extern "C" { typedef void (*kdf_func)(char *passwd, 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); diff --git a/partition.cpp b/partition.cpp index 20ceda141..57a692349 100644 --- a/partition.cpp +++ b/partition.cpp @@ -50,6 +50,14 @@ extern "C" { #ifdef USE_EXT4 #include "make_ext4fs.h" #endif + +#ifdef TW_INCLUDE_CRYPTO + #ifdef TW_INCLUDE_JB_CRYPTO + #include "crypto/jb/cryptfs.h" + #else + #include "crypto/ics/cryptfs.h" + #endif +#endif } #ifdef HAVE_SELINUX #include "selinux/selinux.h" @@ -290,14 +298,38 @@ bool TWPartition::Process_Fstab_Line(string Line, bool Display_Error) { Decrypted_Block_Device = crypto_blkdev; LOGINFO("Data already decrypted, new block device: '%s'\n", crypto_blkdev); } else if (!Mount(false)) { - Is_Encrypted = true; - Is_Decrypted = false; - Can_Be_Mounted = false; - Current_File_System = "emmc"; - Setup_Image(Display_Error); - DataManager::SetValue(TW_IS_ENCRYPTED, 1); - DataManager::SetValue(TW_CRYPTO_PASSWORD, ""); - DataManager::SetValue("tw_crypto_display", ""); + if (Is_Present) { +#ifdef TW_INCLUDE_JB_CRYPTO + // No extra flags needed +#else + property_set("ro.crypto.fs_type", CRYPTO_FS_TYPE); + property_set("ro.crypto.fs_real_blkdev", CRYPTO_REAL_BLKDEV); + property_set("ro.crypto.fs_mnt_point", CRYPTO_MNT_POINT); + property_set("ro.crypto.fs_options", CRYPTO_FS_OPTIONS); + property_set("ro.crypto.fs_flags", CRYPTO_FS_FLAGS); + property_set("ro.crypto.keyfile.userdata", CRYPTO_KEY_LOC); +#ifdef CRYPTO_SD_FS_TYPE + property_set("ro.crypto.sd_fs_type", CRYPTO_SD_FS_TYPE); + property_set("ro.crypto.sd_fs_real_blkdev", CRYPTO_SD_REAL_BLKDEV); + property_set("ro.crypto.sd_fs_mnt_point", EXPAND(TW_INTERNAL_STORAGE_PATH)); +#endif + property_set("rw.km_fips_status", "ready"); +#endif + if (cryptfs_check_footer() == 0) { + Is_Encrypted = true; + Is_Decrypted = false; + Can_Be_Mounted = false; + Current_File_System = "emmc"; + Setup_Image(Display_Error); + DataManager::SetValue(TW_IS_ENCRYPTED, 1); + DataManager::SetValue(TW_CRYPTO_PASSWORD, ""); + DataManager::SetValue("tw_crypto_display", ""); + } else { + LOGERR("Could not mount /data and unable to find crypto footer.\n"); + } + } else { + LOGERR("Primary block device '%s' for mount point '%s' is not present!\n", Primary_Block_Device.c_str(), Mount_Point.c_str()); + } } else { // Filesystem is not encrypted and the mount // succeeded, so get it back to the original diff --git a/partitionmanager.cpp b/partitionmanager.cpp index e8b362cf6..e6193f919 100644 --- a/partitionmanager.cpp +++ b/partitionmanager.cpp @@ -1383,9 +1383,9 @@ int TWPartitionManager::Decrypt_Device(string Password) { property_set("ro.crypto.keyfile.userdata", CRYPTO_KEY_LOC); #ifdef CRYPTO_SD_FS_TYPE - property_set("ro.crypto.sd_fs_type", CRYPTO_SD_FS_TYPE); - property_set("ro.crypto.sd_fs_real_blkdev", CRYPTO_SD_REAL_BLKDEV); - property_set("ro.crypto.sd_fs_mnt_point", EXPAND(TW_INTERNAL_STORAGE_PATH)); + property_set("ro.crypto.sd_fs_type", CRYPTO_SD_FS_TYPE); + property_set("ro.crypto.sd_fs_real_blkdev", CRYPTO_SD_REAL_BLKDEV); + property_set("ro.crypto.sd_fs_mnt_point", EXPAND(TW_INTERNAL_STORAGE_PATH)); #endif property_set("rw.km_fips_status", "ready"); -- cgit v1.2.3