This library contains all cryptographic functions that are used by Cryptomator for iOS. The purpose of this project is to provide a separate light-weight library with its own release cycle that can be used in other projects, too.
For more information on the Cryptomator encryption scheme, visit the security architecture page on docs.cryptomator.org.
You can use Swift Package Manager.
.package(url: "https://github.com/cryptomator/cryptolib-swift.git", .upToNextMinor(from: "1.0.0"))
Masterkey is a class that only contains the key material for AES encryption/decryption and MAC authentication.
This will create a new masterkey with secure random bytes.
let masterkey = try Masterkey.createNew()
Another way is to create a masterkey from raw bytes.
let aesMasterKey = ... let macMasterKey = ... let masterkey = Masterkey.createFromRaw(aesMasterKey: aesMasterKey, macMasterKey: macMasterKey)
MasterkeyFile is a representation of the masterkey file. With that, you can unlock a masterkey file (and get a
Masterkey), lock a masterkey file (and serialize it as JSON), or change the passphrase.
Create a masterkey file with content provided either from URL:
let url = ... let masterkeyFile = try MasterkeyFile.withContentFromURL(url: url)
Or from JSON data:
let data = ... let masterkeyFile = try MasterkeyFile.withContentFromData(data: data)
When you have a masterkey file, you can attempt an unlock. When successful, it unwraps the stored encryption and MAC keys into the masterkey, which can be used for the cryptor.
let masterkeyFile = ... let passphrase = ... let pepper = ... // optional let masterkey = try masterkeyFile.unlock(passphrase: passphrase, pepper: pepper)
The unlock process can also be performed in two steps:
let masterkeyFile = ... let passphrase = ... let pepper = ... // optional let kek = try masterkeyFile.deriveKey(passphrase: passphrase, pepper: pepper) let masterkey = try masterkeyFile.unlock(kek: kek)
This is useful if you'd like to derive the key in an extra step since the function is memory-intensive (using scrypt). The result can then be used elsewhere, e.g. in a memory-restricted process.
For persisting the masterkey, use this method to export its encrypted/wrapped masterkey and other metadata as JSON data.
let masterkey = ... let vaultVersion = ... let passphrase = ... let pepper = ... // optional let scryptCostParam = ... // optional let data = try MasterkeyFile.lock(masterkey: masterkey, vaultVersion: vaultVersion, passphrase: passphrase, pepper: pepper, scryptCostParam: scryptCostParam)
The masterkey can be re-encrypted with a new passphrase.
let masterkeyFileData = ... let oldPassphrase = ... let newPassphrase = ... let pepper = ... // optional let scryptCostParam = ... // optional try MasterkeyFile.changePassphrase(masterkeyFileData: masterkeyFileData, oldPassphrase: oldPassphrase, newPassphrase: newPassphrase, pepper: pepper, scryptCostParam: scryptCostParam)
Cryptor is the core class for cryptographic operations on Cryptomator vaults.
Create a cryptor by providing a masterkey.
let masterkey = ... let cryptor = Cryptor(masterkey: masterkey)
Encrypt the directory ID in order to determine the encrypted directory URL.
let cryptor = ... let dirId = ... let encryptedDirId = try cryptor.encryptDirId(dirId)
Encrypt and decrypt filenames by providing a directory ID.
let cryptor = ... let filename = ... let dirId = ... let ciphertextName = try cryptor.encryptFileName(filename, dirId: dirId) let cleartextName = try cryptor.decryptFileName(ciphertextName, dirId: dirId)
Encrypt and decrypt file content via URLs. These methods support implicit progress composition.
let cryptor = ... let fileURL = ... let ciphertextURL = ... let cleartextURL = ... try cryptor.encryptContent(from: fileURL, to: ciphertextURL) try cryptor.decryptContent(from: ciphertextURL, to: cleartextURL)
Determine the cleartext and ciphertext sizes in O(1).
let cryptor = ... let size = ... let ciphertextSize = cryptor.calculateCiphertextSize(size) let cleartextSize = try cryptor.calculateCleartextSize(ciphertextSize)
Please read our contribution guide, if you would like to report a bug, ask a question or help us with coding.
In general, the following preference is used to choose the implementation of cryptographic primitives:
Please make sure that your code is correctly formatted and passes linter validations. The easiest way to do that is to set up a pre-commit hook. Create a file at
.git/hooks/pre-commit with this content:
./Scripts/process.sh --staged exit $?
And make your pre-commit hook executable:
chmod +x .git/hooks/pre-commit
Help us keep Cryptomator open and inclusive. Please read and follow our Code of Conduct.
Distributed under the AGPLv3. See the LICENSE file for more info.
|Last commit: 2 weeks ago|