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    Import std.crypto.derive

    std.crypto.derive

    HMAC, HKDF, and PBKDF2: message authentication and key derivation.

    Hmac, Hkdf, and Pbkdf2, over mbedTLS: a MAC, which a key makes and checks, a key from other key material, and a key from a password: HMAC and PBKDF2 by SHA-1, SHA-256, or SHA-512, and HKDF by SHA-256 or SHA-512.

    std/crypto/derive.fb

    Types

    Hmac struct 

    Public Struct Hmac

    HMAC (RFC 2104) of data with key, of any length: a MAC as long as its hash, which only who has the key can make. Check one with ConstantTimeEquals.

    Examples

    Local message = "The quick brown fox jumps over the lazy dog"
Local mac = Hmac.Sha256("key".Bytes, message)
Expect(Hex.Encode(mac) == "f7bc83f430538424b13298e6aa6fb143ef4d59a14946175997479dbc2d1a3cd8")
// A MAC that came with a message is checked without telling where they differ.
Expect(ConstantTimeEquals(mac, Hmac.Sha256("key".Bytes, message)))

    std/crypto/derive.fb, line 35

    • Public Static Method Sha1(key: UInt8[], data: UInt8[]): UInt8[] static method #

      HMAC-SHA1's 20 bytes, for the formats that ask for it.

    • Public Static Method Sha1(key: UInt8[], text: String): UInt8[] static method #

      HMAC-SHA1 of text's UTF-8 bytes with key.

    • Public Static Method Sha256(key: UInt8[], data: UInt8[]): UInt8[] static method #

      HMAC-SHA256's 32 bytes.

    • Public Static Method Sha256(key: UInt8[], text: String): UInt8[] static method #

      HMAC-SHA256 of text's UTF-8 bytes with key.

    • Public Static Method Sha512(key: UInt8[], data: UInt8[]): UInt8[] static method #

      HMAC-SHA512's 64 bytes.

    • Public Static Method Sha512(key: UInt8[], text: String): UInt8[] static method #

      HMAC-SHA512 of text's UTF-8 bytes with key.

    Hkdf struct 

    Public Struct Hkdf

    HKDF (RFC 5869): length bytes of new key from material, a secret like a shared one from X25519, with salt, which can be empty, and info, which says what the key is for, so keys for different uses differ.

    Examples

    Local shared = SecureRandom.Bytes(32)
Local key = Hkdf.Sha256(shared, [], "session keys".Bytes, 32)
Expect(key.Count == 32)
Expect(key == Hkdf.Sha256(shared, [], "session keys".Bytes, 32))

    std/crypto/derive.fb, line 72

    • @PanicsAtCaller Public Static Method Sha256(material: UInt8[], salt: UInt8[], info: UInt8[], length: Int): UInt8[] static method #

      length bytes of key from material, salt, and info, by HMAC-SHA256. Panics unless length is from 0 to 8160, 255 hashes.

    • @PanicsAtCaller Public Static Method Sha512(material: UInt8[], salt: UInt8[], info: UInt8[], length: Int): UInt8[] static method #

      length bytes of key from material, salt, and info, by HMAC-SHA512. Panics unless length is from 0 to 16320, 255 hashes.

    Pbkdf2 struct 

    Public Struct Pbkdf2

    PBKDF2 (RFC 8018) with HMAC: length bytes of key from password and salt, in iterations rounds, which make a guess at the password cost that many. For keeping passwords, Argon2id is stronger, since it needs memory too. Each panics unless iterations is 1 or more and length isn't negative.

    Examples

    Local salt = SecureRandom.Bytes(16)
Local key = Pbkdf2.Sha256("correct horse", salt, 1000, 32)
Expect(key.Count == 32)
Expect(key == Pbkdf2.Sha256("correct horse", salt, 1000, 32))

    std/crypto/derive.fb, line 107

    • @PanicsAtCaller Public Static Method Sha1(password: String, salt: UInt8[], iterations: Int, length: Int): UInt8[] static method #

      By SHA-1, for the formats that ask for it.

    • @PanicsAtCaller Public Static Method Sha1(password: UInt8[], salt: UInt8[], iterations: Int, length: Int): UInt8[] static method #

      A key derived from the bytes of password by SHA-1, as the one that takes a String does.

    • @PanicsAtCaller Public Static Method Sha256(password: String, salt: UInt8[], iterations: Int, length: Int): UInt8[] static method #

      A key from password and salt, in iterations rounds of HMAC-SHA256.

    • @PanicsAtCaller Public Static Method Sha256(password: UInt8[], salt: UInt8[], iterations: Int, length: Int): UInt8[] static method #

      A key derived from the bytes of password by SHA-256, as the one that takes a String does.

    • @PanicsAtCaller Public Static Method Sha512(password: String, salt: UInt8[], iterations: Int, length: Int): UInt8[] static method #

      A key from password and salt, in iterations rounds of HMAC-SHA512.

    • @PanicsAtCaller Public Static Method Sha512(password: UInt8[], salt: UInt8[], iterations: Int, length: Int): UInt8[] static method #

      A key derived from the bytes of password by SHA-512, as the one that takes a String does.

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