ECDHESSwift

Features

• JWE: Key Agreement with Elliptic Curve Diffie-Hellman Ephemeral Static (ECDH-ES) arbitrary data encryption and decryption.

Elliptic Curve

• P-256
• P-384
• P-521

Key Management Algorithms

• ECDH-ES: Elliptic Curve Diffie-Hellman Ephemeral Static key agreement using Concat KDF.
• ECDH-ES+A128KW: ECDH-ES using Concat KDF and CEK wrapped with "A128KW".
• ECDH-ES+A192KW: ECDH-ES using Concat KDF and CEK wrapped with "A192KW".
• ECDH-ES+A256KW: ECDH-ES using Concat KDF and CEK wrapped with "A256KW".

Encryption Algorithms

• A128CBC-HS256: AES_128_CBC_HMAC_SHA_256 authenticated encryption algorithm.
• A192CBC-HS384: AES_192_CBC_HMAC_SHA_384 authenticated encryption algorithm.
• A256CBC-HS512: AES_256_CBC_HMAC_SHA_512 authenticated encryption algorithm.
• A128GCM: AES GCM using 128-bit key.
• A192GCM: AES GCM using 192-bit key.
• A256GCM: AES GCM using 256-bit key.

Compression Algorithms

• DEF: Compression with the DEFLATE [RFC1951] algorithm.

JWE Serializations

• Compact Serialization

Requirements

• iOS >= 10.0
• JOSESwift 1.8

Installation

ECDHESSwift is available through CocoaPods. To install it, simply add the following line to your Podfile:

pod 'ECDHESSwift'

Usage

Encryption

let pubJwk = """
  {
    "crv": "P-256",
    "kty": "EC",
    "x": "CQJxA68WhgU3hztigbedfLtJitDhScq3XSnXgO0FV5o",
    "y": "WFg6s36izURa733WqeoJ8zXMd7ho5OSwdWnMsEPgTEI"
  }
"""

let plaintext = """
每覽昔人興感之由，若合一契，未嘗不臨文嗟悼，不能喻之於懷，固知一死生為虛誕，彭殤為妄作。後之視今，亦猶今之視昔，悲夫！故列時人，錄其所述，雖世殊事異，所以興懷，其致一也。後之覽者，亦將有感於斯文。
""".data(using: .utf8)!

let encryptionJwe = try EcdhEsJwe(plaintext: plaintext, pubKeyJwkJson: pubJwk, headerDic: ["alg": "ECDH-ES+A256KW", "enc": "A256GCM"])

let jweCompactString = encryptionJwe.compactSerializedString

Decryption

let privJwk = """
  {
    "crv": "P-256",
    "d": "920OCD0fW97YXbQNN-JaOtaDgbuNyVxXgKwjfXPPqv4",
    "kty": "EC",
    "x": "CQJxA68WhgU3hztigbedfLtJitDhScq3XSnXgO0FV5o",
    "y": "WFg6s36izURa733WqeoJ8zXMd7ho5OSwdWnMsEPgTEI"
  }
"""

let jweCompactString = "eyJhbGciOiJFQ0RILUVTK0EyNTZLVyIsImVuYyI6IkEyNTZHQ00iLCJlcGsiOnsieSI6IkgwX1JwdTBqaHpjcVdiaFRiNjg0OVcyZV9xQkxIVFNXSnVYQVYyRjRmeGsiLCJraWQiOiIxQUJBM0UxOS00RTlFLTRFNTAtOTAxOC01NDY5OTExMEY2NTciLCJrdHkiOiJFQyIsImNydiI6IlAtMjU2IiwieCI6IkIxUGxLWW10ekdUemFUT2FPd1F1aEVKOXFFNDIyVVpEaHlWNHZkSGpZdlkifX0.eD9Mxp9SBS6QMRh-rP-shwmM0fCj34ZHDUBjdADgndl_J4qIk60OWA.P_pq05ZWReabvX1a.a9YuXgj1EI-DOgWq8da8H8c1P7Qn4LMiJt81My3uC9SmV9NHY6vKtqFVlB1TLHdJ7niT68Gd_T5ow_K_BUOm57armWx9UAaTBLV8gWETRhtmF7vCEPZEVIrK07aTHRvhkF57BBlgeMbpIfuXAL8Ks_S5Y_0WkzjBfpMCx0y7I4UPUYc6aaJLxkDlz0L54HiPpJD7jx1ExPZ_b6QHVbLHnQrywOPBZXbRIax-g8GuTW1MYhazIoKyStSmImHJxMBiA5OkfxuGaiLiz8_UpUyDqEbFDYJl_gDm-ePZbNhcM46XFL0SQidNOmcrmzXMjOMNDTpG3zVCg05EkM7Ztm-bIuOSRAWwYDLc92cDlSCzfH_77p3UWhMiRZicrrLULUXnkKi-gOeg.TOEKC6oNaaND_Etb5qxt5A"

let decryptionJwe = try EcdhEsJwe(compactSerializedString: jweCompactString)

let plaintext = try! decryptionJwe.decrypt(privKeyJwkJson: privJwk)