Dopo aver letto le altre risposte qui (e aver bisogno di supportare anche altri tipi di hash) ho scritto un'estensione String che gestisce più tipi di hash e tipi di output.
NOTA: CommonCrypto è incluso in Xcode 10, quindi puoi semplicemente import CommonCrypto
senza dover scherzare con un'intestazione di bridging se hai installato l'ultima versione di Xcode ... Altrimenti è necessaria un'intestazione di bridging.
AGGIORNAMENTO: Sia Swift 4 che 5 utilizzano lo stesso file String + Crypto.swift di seguito.
Esiste un file Data + Crypto.swift separato per Swift 5 (vedi sotto) poiché l'API per "withUnsafeMutableBytes" e "withUnsafeBytes" è stato modificato tra Swift 4 e 5.
String + Crypto.swift - (sia per Swift 4 che per 5)
import Foundation
import CommonCrypto
// Defines types of hash string outputs available
public enum HashOutputType {
// standard hex string output
case hex
// base 64 encoded string output
case base64
}
// Defines types of hash algorithms available
public enum HashType {
case md5
case sha1
case sha224
case sha256
case sha384
case sha512
var length: Int32 {
switch self {
case .md5: return CC_MD5_DIGEST_LENGTH
case .sha1: return CC_SHA1_DIGEST_LENGTH
case .sha224: return CC_SHA224_DIGEST_LENGTH
case .sha256: return CC_SHA256_DIGEST_LENGTH
case .sha384: return CC_SHA384_DIGEST_LENGTH
case .sha512: return CC_SHA512_DIGEST_LENGTH
}
}
}
public extension String {
/// Hashing algorithm for hashing a string instance.
///
/// - Parameters:
/// - type: The type of hash to use.
/// - output: The type of output desired, defaults to .hex.
/// - Returns: The requested hash output or nil if failure.
public func hashed(_ type: HashType, output: HashOutputType = .hex) -> String? {
// convert string to utf8 encoded data
guard let message = data(using: .utf8) else { return nil }
return message.hashed(type, output: output)
}
}
SWIFT 5 - Dati + Crypto.swift
import Foundation
import CommonCrypto
extension Data {
/// Hashing algorithm that prepends an RSA2048ASN1Header to the beginning of the data being hashed.
///
/// - Parameters:
/// - type: The type of hash algorithm to use for the hashing operation.
/// - output: The type of output string desired.
/// - Returns: A hash string using the specified hashing algorithm, or nil.
public func hashWithRSA2048Asn1Header(_ type: HashType, output: HashOutputType = .hex) -> String? {
let rsa2048Asn1Header:[UInt8] = [
0x30, 0x82, 0x01, 0x22, 0x30, 0x0d, 0x06, 0x09, 0x2a, 0x86, 0x48, 0x86,
0xf7, 0x0d, 0x01, 0x01, 0x01, 0x05, 0x00, 0x03, 0x82, 0x01, 0x0f, 0x00
]
var headerData = Data(rsa2048Asn1Header)
headerData.append(self)
return hashed(type, output: output)
}
/// Hashing algorithm for hashing a Data instance.
///
/// - Parameters:
/// - type: The type of hash to use.
/// - output: The type of hash output desired, defaults to .hex.
/// - Returns: The requested hash output or nil if failure.
public func hashed(_ type: HashType, output: HashOutputType = .hex) -> String? {
// setup data variable to hold hashed value
var digest = Data(count: Int(type.length))
_ = digest.withUnsafeMutableBytes{ digestBytes -> UInt8 in
self.withUnsafeBytes { messageBytes -> UInt8 in
if let mb = messageBytes.baseAddress, let db = digestBytes.bindMemory(to: UInt8.self).baseAddress {
let length = CC_LONG(self.count)
switch type {
case .md5: CC_MD5(mb, length, db)
case .sha1: CC_SHA1(mb, length, db)
case .sha224: CC_SHA224(mb, length, db)
case .sha256: CC_SHA256(mb, length, db)
case .sha384: CC_SHA384(mb, length, db)
case .sha512: CC_SHA512(mb, length, db)
}
}
return 0
}
}
// return the value based on the specified output type.
switch output {
case .hex: return digest.map { String(format: "%02hhx", $0) }.joined()
case .base64: return digest.base64EncodedString()
}
}
}
SWIFT 4 - Dati + Crypto.swift
import Foundation
import CommonCrypto
extension Data {
/// Hashing algorithm that prepends an RSA2048ASN1Header to the beginning of the data being hashed.
///
/// - Parameters:
/// - type: The type of hash algorithm to use for the hashing operation.
/// - output: The type of output string desired.
/// - Returns: A hash string using the specified hashing algorithm, or nil.
public func hashWithRSA2048Asn1Header(_ type: HashType, output: HashOutputType = .hex) -> String? {
let rsa2048Asn1Header:[UInt8] = [
0x30, 0x82, 0x01, 0x22, 0x30, 0x0d, 0x06, 0x09, 0x2a, 0x86, 0x48, 0x86,
0xf7, 0x0d, 0x01, 0x01, 0x01, 0x05, 0x00, 0x03, 0x82, 0x01, 0x0f, 0x00
]
var headerData = Data(bytes: rsa2048Asn1Header)
headerData.append(self)
return hashed(type, output: output)
}
/// Hashing algorithm for hashing a Data instance.
///
/// - Parameters:
/// - type: The type of hash to use.
/// - output: The type of hash output desired, defaults to .hex.
/// - Returns: The requested hash output or nil if failure.
public func hashed(_ type: HashType, output: HashOutputType = .hex) -> String? {
// setup data variable to hold hashed value
var digest = Data(count: Int(type.length))
// generate hash using specified hash type
_ = digest.withUnsafeMutableBytes { (digestBytes: UnsafeMutablePointer<UInt8>) in
self.withUnsafeBytes { (messageBytes: UnsafePointer<UInt8>) in
let length = CC_LONG(self.count)
switch type {
case .md5: CC_MD5(messageBytes, length, digestBytes)
case .sha1: CC_SHA1(messageBytes, length, digestBytes)
case .sha224: CC_SHA224(messageBytes, length, digestBytes)
case .sha256: CC_SHA256(messageBytes, length, digestBytes)
case .sha384: CC_SHA384(messageBytes, length, digestBytes)
case .sha512: CC_SHA512(messageBytes, length, digestBytes)
}
}
}
// return the value based on the specified output type.
switch output {
case .hex: return digest.map { String(format: "%02hhx", $0) }.joined()
case .base64: return digest.base64EncodedString()
}
}
}
Modifica: poiché l'hash si verifica effettivamente sui dati, ho suddiviso l'algoritmo di hashing in un'estensione dati. Ciò consente di utilizzare lo stesso algoritmo anche per le operazioni hash di blocco del certificato SSL.
Ecco un breve esempio di come potresti usarlo per un'operazione di blocco SSL:
// Certificate pinning - get certificate as data
let data: Data = SecCertificateCopyData(serverCertificate) as Data
// compare hash of server certificate with local (expected) hash value
guard let serverHash = data.hashWithRSA2048Asn1Header(.sha256, output: .base64), serverHash == storedHash else {
print("SSL PINNING: Server certificate hash does not match specified hash value.")
return false
}
torna alla risposta originale
Ho testato gli algoritmi hash usando questo:
let value = "This is my string"
if let md5 = value.hashed(.md5) {
print("md5: \(md5)")
}
if let sha1 = value.hashed(.sha1) {
print("sha1: \(sha1)")
}
if let sha224 = value.hashed(.sha224) {
print("sha224: \(sha224)")
}
if let sha256 = value.hashed(.sha256) {
print("sha256: \(sha256)")
}
if let sha384 = value.hashed(.sha384) {
print("sha384: \(sha384)")
}
if let sha512 = value.hashed(.sha512) {
print("sha512: \(sha512)")
}
e questo è il risultato stampato:
md5: c2a9ce57e8df081b4baad80d81868bbb
sha1: 37fb219bf98bee51d2fdc3ba6d866c97f06c8223
sha224: f88e2f20aa89fb4dffb6bdc62d7bd75e1ba02574fae4a437c3bf49c7
sha256: 9da6c02379110815278b615f015f0b254fd3d5a691c9d8abf8141655982c046b
sha384: d9d7fc8aefe7f8f0a969b132a59070836397147338e454acc6e65ca616099d03a61fcf9cc8c4d45a2623145ebd398450
sha512: 349cc35836ba85915ace9d7f895b712fe018452bb4b20ff257257e12adeb1e83ad780c6568a12d03f5b2cb1e3da23b8b7ced9012a188ef3855e0a8f3db211883