SwCrypt

Create public and private RSA keys in DER format

let (privateKey, publicKey) = try! CC.RSA.generateKeyPair(2048)

Convert them to PEM format

let privateKeyPEM = try SwKeyConvert.PrivateKey.derToPKCS1PEM(privateKey)
let publicKeyPEM = SwKeyConvert.PublicKey.derToPKCS8PEM(publicKey)

Or read them from strings with PEM data

let privateKeyDER = SwKeyConvert.PrivateKey.pemToPKCS1DER(privateKeyPEM)
let publicKeyDER = SwKeyConvert.PublicKey.pemToPKCS1DER(publicKeyPEM)

Or encrypt, decrypt the private key (OpenSSL compatible)

try SwKeyConvert.PrivateKey.encryptPEM(privateKeyPEM, passphrase: "longpassword", mode: .aes256CBC)
try SwKeyConvert.PrivateKey.decryptPEM(privEncrypted, passphrase: "longpassword")

Encrypt, decrypt data with RSA

try CC.RSA.encrypt(data, derKey: publicKey, tag: tag, padding: .oaep, digest: .sha1)
try CC.RSA.decrypt(data, derKey: privateKey, tag: tag, padding: .oaep, digest: .sha1)

Sign, verify data with RSA

let sign = try? CC.RSA.sign(testMessage, derKey: privKey, padding: .pss, 
 digest: .sha256, saltLen: 16)
let verified = try? CC.RSA.verify(testMessage, derKey: pubKey, padding: .pss,
 digest: .sha256, saltLen: 16, signedData: sign!)

Elliptic curve functions

let keys = try? CC.EC.generateKeyPair(384)
let signed = try? CC.EC.signHash(keys!.0, hash: hash)
let verified = try? CC.EC.verifyHash(keys!.1, hash: hash, signedData: signed!)

let shared = try? CC.EC.computeSharedSecret(keys!.0, publicKey: partnerPubKey)

Diffie-Hellman functions

let dh = try CC.DH.DH(dhParam: .rfc3526Group5)
let myPubKey = try dh.generateKey()
let commonKey = try dh.computeKey(partnerPubKey!)

Encrypt, decrypt data with symmetric ciphers

try CC.crypt(.encrypt, blockMode: .cbc, algorithm: .aes, padding: .pkcs7Padding, data: data, key: aesKey, iv: iv)
try CC.crypt(.decrypt, blockMode: .cfb, algorithm: .aes, padding: .pkcs7Padding, data: data, key: aesKey, iv: iv)

Encrypt, decrypt data with symmetric authenticating ciphers

try CC.cryptAuth(.encrypt, blockMode: .gcm, algorithm: .aes, data: data, aData: aData, key: aesKey, iv: iv, tagLength: tagLength)
try CC.cryptAuth(.decrypt, blockMode: .ccm, algorithm: .aes, data: data, aData: aData, key: aesKey, iv: iv, tagLength: tagLength)

Digest functions

CC.digest(data, alg: .md5)
CC.digest(data, alg: .sha256)
CC.digest(data, alg: .sha512)

HMAC function

CC.HMAC(data, alg: .sha512, key: key)

CMAC function

CC.CMAC.AESCMAC(input, key: key)

CRC function

let output = try? CC.CRC.crc(input, mode: .crc32)

KeyDerivation

CC.KeyDerivation.PBKDF2(password, salt: salt, prf: .sha256, rounds: 4096)

Symmetric Key Wrapping

try CC.KeyWrap.SymmetricKeyWrap(CC.KeyWrap.rfc3394IV, kek: kek, rawKey: rawKey)
try CC.KeyWrap.SymmetricKeyUnwrap(CC.KeyWrap.rfc3394IV, kek: kek, wrappedKey: wrappedKey)

Upsert, get, delete keys from KeyStore

try SwKeyStore.upsertKey(privateKeyPEM, keyTag: "priv", options: [kSecAttrAccessible:kSecAttrAccessibleWhenUnlockedThisDeviceOnly])
try SwKeyStore.getKey("priv")
try SwKeyStore.delKey("priv")

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Check availability

SwCrypt uses dlopen and dlsym to load the CommonCrypto's functions, because not all of them are available in public header files. You have to check the availability before using them.

let digestAvailable : Bool = CC.digestAvailable()
let ramdomAvailable : Bool = CC.randomAvailable(()
let hmacAvailable : Bool = CC.hmacAvailable()
let cryptorAvailable : Bool = CC.cryptorAvailable
let keyDerivationAvailable : Bool = CC.KeyDerivation.available()
let keyWrapAvailable : Bool = CC.KeyWrap.available()
let rsaAvailable : Bool = CC.RSA.available()
let dhAvailable : Bool = CC.DH.available()
let ecAvailable : Bool = CC.EC.available()
let crcAvailable : Bool = CC.CRC.available()
let cmacAvailable : Bool = CC.CMAC.available()
let gcmAvailable : Bool = CC.GCM.available()
let ccmAvailable : Bool = CC.CCM.available()

or all in one turn:
let ccAvailable : Bool = CC.available()

Install

Just copy SwCrypt.swift to your project or use the Carthage dependency manager.

Inspired from

• http://blog.flirble.org/2011/01/05/rsa-public-key-openssl-ios/
• https://github.com/lancy/RSADemo
• https://github.com/TakeScoop/SwiftyRSA
• https://github.com/henrinormak/Heimdall
• https://github.com/btnguyen2k/swift-rsautils

License

This project is copyrighted under the MIT license.