Support for private (adopted) volumes.
This adds support for private volumes which is just a filesystem
wrapped in a dm-crypt layer. For now we're using the exact same
configuration as internal encryption (aes-cbc-essiv:sha256), but we
don't store any key material on the removable media. Instead, we
store the key on internal storage, and use the GPT partition GUID
to identify which key should be used.
This means that private external storage is effectively as secure as
the internal storage of the device. That is, if the internal storage
is encrypted, then our external storage key is also encrypted.
When partitioning disks, we now support a "private" mode which has
a PrivateVolume partition, and a currently unused 16MB metadata
partition reserved for future use. It also supports a "mixed" mode
which creates both a PublicVolume and PrivateVolume on the same
disk. Mixed mode is currently experimental.
For now, just add ext4 support to PrivateVolume; we'll look at f2fs
in a future change. Add VolumeBase lifecycle for setting up crypto
mappings, and extract blkid logic into shared method. Sprinkle some
more "static" around the cryptfs code to improve invariants.
Bug: 19993667
Change-Id: Ibd1df6250735b706959a1eb9d9f7219ea85912a0
diff --git a/Utils.h b/Utils.h
index 660ef19..0e0904e 100644
--- a/Utils.h
+++ b/Utils.h
@@ -19,6 +19,7 @@
#include <utils/Errors.h>
+#include <vector>
#include <string>
// DISALLOW_COPY_AND_ASSIGN disallows the copy and operator= functions. It goes in the private:
@@ -41,6 +42,18 @@
/* Creates bind mount from source to target */
status_t BindMount(const std::string& source, const std::string& target);
+/* Reads filesystem metadata from device at path */
+status_t ReadMetadata(const std::string& path, std::string& fsType,
+ std::string& fsUuid, std::string& fsLabel);
+
+status_t ForkExecvp(const std::vector<std::string>& args, int* status,
+ bool ignore_int_quit, bool logwrap);
+
+status_t ReadRandomBytes(size_t bytes, std::string& out);
+
+status_t HexToStr(const std::string& hex, std::string& str);
+status_t StrToHex(const std::string& str, std::string& hex);
+
} // namespace vold
} // namespace android