Crypto
The built-in contract Crypto
can be used to perform cryptographic operations.
The contract can be imported using import Crypto
.
For example, to verify two signatures with equal weights for some signed data:
import Crypto
pub fun test main() {
let keyList = Crypto.KeyList()
let publicKeyA = Crypto.PublicKey(
publicKey:
"db04940e18ec414664ccfd31d5d2d4ece3985acb8cb17a2025b2f1673427267968e52e2bbf3599059649d4b2cce98fdb8a3048e68abf5abe3e710129e90696ca".decodeHex(),
signatureAlgorithm: Crypto.ECDSA_P256
)
keyList.add(
publicKeyA,
hashAlgorithm: Crypto.SHA3_256,
weight: 0.5
)
let publicKeyB = Crypto.PublicKey(
publicKey:
"df9609ee588dd4a6f7789df8d56f03f545d4516f0c99b200d73b9a3afafc14de5d21a4fc7a2a2015719dc95c9e756cfa44f2a445151aaf42479e7120d83df956".decodeHex(),
signatureAlgorithm: Crypto.ECDSA_P256
)
keyList.add(
publicKeyB,
hashAlgorithm: Crypto.SHA3_256,
weight: 0.5
)
let signatureSet = [
Crypto.KeyListSignature(
keyIndex: 0,
signature:
"8870a8cbe6f44932ba59e0d15a706214cc4ad2538deb12c0cf718d86f32c47765462a92ce2da15d4a29eb4e2b6fa05d08c7db5d5b2a2cd8c2cb98ded73da31f6".decodeHex()
),
Crypto.KeyListSignature(
keyIndex: 1,
signature:
"bbdc5591c3f937a730d4f6c0a6fde61a0a6ceaa531ccb367c3559335ab9734f4f2b9da8adbe371f1f7da913b5a3fdd96a871e04f078928ca89a83d841c72fadf".decodeHex()
)
]
// "foo", encoded as UTF-8, in hex representation
let signedData = "666f6f".decodeHex()
let isValid = keyList.isValid(
signatureSet: signatureSet,
signedData: signedData
)
}
The API of the Crypto contract is:
pub contract Crypto {
pub struct SignatureAlgorithm {
pub let name: String
}
/// ECDSA_P256 is Elliptic Curve Digital Signature Algorithm (ECDSA) on the NIST P-256 curve
pub let ECDSA_P256: SignatureAlgorithm
/// ECDSA_Secp256k1 is Elliptic Curve Digital Signature Algorithm (ECDSA) on the secp256k1 curve
pub let ECDSA_Secp256k1: SignatureAlgorithm
pub struct HashAlgorithm {
pub let name: String
}
/// SHA2_256 is Secure Hashing Algorithm 2 (SHA-2) with a 256-bit digest
pub let SHA2_256: HashAlgorithm
/// SHA3_256 is Secure Hashing Algorithm 3 (SHA-3) with a 256-bit digest
pub let SHA3_256: HashAlgorithm
pub struct PublicKey {
pub let publicKey: [UInt8]
pub let signatureAlgorithm: SignatureAlgorithm
init(publicKey: [UInt8], signatureAlgorithm: SignatureAlgorithm)
}
pub struct KeyListEntry {
pub let keyIndex: Int
pub let publicKey: PublicKey
pub let hashAlgorithm: HashAlgorithm
pub let weight: UFix64
pub let isRevoked: Bool
init(
keyIndex: Int,
publicKey: PublicKey,
hashAlgorithm: HashAlgorithm,
weight: UFix64,
isRevoked: Bool
)
}
pub struct KeyList {
init()
/// Adds a new key with the given weight
pub fun add(
_ publicKey: PublicKey,
hashAlgorithm: HashAlgorithm,
weight: UFix64
)
/// Returns the key at the given index, if it exists.
/// Revoked keys are always returned, but they have `isRevoked` field set to true
pub fun get(keyIndex: Int): KeyListEntry?
/// Marks the key at the given index revoked, but does not delete it
pub fun revoke(keyIndex: Int)
/// Returns true if the given signatures are valid for the given signed data
pub fun isValid(
signatureSet: [KeyListSignature],
signedData: [UInt8]
): Bool
}
pub struct KeyListSignature {
pub let keyIndex: Int
pub let signature: [UInt8]
pub init(keyIndex: Int, signature: [UInt8])
}
}