Ecc Lianja Reference Documentation
Ecc
Current Version: 10.1.2
Elliptical Curve Cryptography class for generating ECDSA keys, computing shared secrets, and creating and verifying ECDSA signatures. Supports the following curves:
- secp256r1 (also known as P-256 and prime256v1)
- secp384r1 (also known as P-384)
- secp521r1 (also known as P-521)
- secp256k1 (This is the curve used for Bitcoin)
- secp192r1
- secp224r1
- brainpoolP160r1
- brainpoolP192r1
- brainpoolP192r1
- brainpoolP224r1
- brainpoolP256r1
- brainpoolP320r1
- brainpoolP384r1
- brainpoolP512r1
Additional curves will be supported in the future.
Object Creation
loObject = createobject("CkEcc")
Properties
AsnFormat
If .T., the ECDSA signatures produced by this object will use ASN.1 format. Otherwise the ECDSA signature will be a concatenation of the two raw byte arrays for r and s.
ECDSA signatures have two equal sized parts, r and s. There are two common formats for encoding the signature:
(a) Concatenating the raw byte array of r and s
(b) Encoding both into a structured ASN.1 / DER sequence.
DebugLogFilePath
If set to a file path, this property logs the LastErrorText of each Chilkat method or property call to the specified file. This logging helps identify the context and history of Chilkat calls leading up to any crash or hang, aiding in debugging.
Enabling the VerboseLogging property provides more detailed information. This property is mainly used for debugging rare instances where a Chilkat method call causes a hang or crash, which should generally not happen.
Possible causes of hangs include:
- A timeout property set to 0, indicating an infinite timeout.
- A hang occurring within an event callback in the application code.
- An internal bug in the Chilkat code causing the hang.
LastErrorHtml
Provides HTML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
topLastErrorText
Provides plain text information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
LastErrorXml
Provides XML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
topLastMethodSuccess
Indicates the success or failure of the most recent method call: .T. means success, .F. means failure. This property remains unchanged by property setters or getters. This method is present to address challenges in checking for null or Nothing returns in certain programming languages.
topVerboseLogging
If set to .T., then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is .F.. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.
topVersion
Methods
GenEccKey
Generates an ECDSA private key. The curveName specifies the curve name which determines the key size. The prng provides a source for generating the random private key.
The following curve names are accepted:
- secp256r1 (also known as P-256 and prime256v1)
- secp384r1 (also known as P-384)
- secp521r1 (also known as P-521)
- secp256k1 (This is the curve used for Bitcoin)
- secp192r1
- secp224r1
- brainpoolP160r1
- brainpoolP192r1
- brainpoolP192r1
- brainpoolP224r1
- brainpoolP256r1
- brainpoolP320r1
- brainpoolP384r1
- brainpoolP512r1
Returns .F. on failure
GenEccKey2
Generates an ECDSA private key using a specified value for K. The curveName specifies the curve name which determines the key size. The encodedK is the encoded value of the private key. The encoding is the encoding used for encodedK, which can be "hex", "base64", "decimal", etc.
Note: This method is typically used for testing -- such as when the same private key is desired to produce results identical from run to run.
The following curve names are accepted:
- secp256r1 (also known as P-256 and prime256v1)
- secp384r1 (also known as P-384)
- secp521r1 (also known as P-521)
- secp256k1 (This is the curve used for Bitcoin)
- secp192r1
- secp224r1
- brainpoolP160r1
- brainpoolP192r1
- brainpoolP192r1
- brainpoolP224r1
- brainpoolP256r1
- brainpoolP320r1
- brainpoolP384r1
- brainpoolP512r1
Returns .F. on failure
SharedSecretENC
Computes a shared secret given a private and public key. For example, Alice and Bob can compute the identical shared secret by doing the following: Alice sends Bob her public key, and Bob calls SharedSecretENC with his private key and Alice's public key. Bob sends Alice his public key, and Alice calls SharedSecretENC with her private key and Bob's public key. Both calls to SharedSecretENC will produce the same result. The resulting bytes are returned in encoded string form (hex, base64, etc) as specified by encoding.
Note: The private and public keys must both be keys on the same ECDSA curve.
Returns .F. on failure
SignBd
This method is the same as SignHashENC, except the actual data to be signed and the name of the hash algorithm is passed in. The following hash algorithms are supported: sha256, sha384, and sha512.
Returns .F. on failure
SignBdUsingCert
Same as SignBd, but instead uses the private key of a certificate (assuming the cert's private key is ECDSA).
Returns .F. on failure
topSignHashENC
Computes an ECDSA signature on a hash. ECDSA signatures are computed and verified on the hashes of data (such as SHA1, SHA256, etc.). The hash of the data is passed in encodedHash. The encoding, such as "base64", "hex", etc. is passed in encoding. The ECDSA private key is passed in the 3rd argument (privkey). Given that creating an ECDSA signature involves the generation of random numbers, a PRNG is passed in the 4th argument (prng). The signature is returned as an encoded string using the encoding specified by the encoding argument.
Returns .F. on failure
SignHashUsingCert
Computes an ECDSA signature on a hash. ECDSA signatures are computed and verified on the hashes of data (such as SHA1, SHA256, etc.). The hash of the data is passed in encodedHash. The encoding, such as "base64", "hex", etc. is passed in encoding. The certificate having a private key is passed in cert. The signature is returned as an encoded string using the encoding specified by the encoding argument.
Returns .F. on failure
topVerifyBd
This method is the same as VerifyHashENC, except the actual data to be verified and the name of the hash algorithm is passed in. The following hash algorithms are supported: sha256, sha384, and sha512.
VerifyHashENC
Verifies an ECDSA signature. ECDSA signatures are computed and verified on the hashes of data (such as SHA1, SHA256, etc.). The hash of the data is passed in encodedHash. The encoded signature is passed in encodedSig. The encoding of both the hash and signature, such as "base64", "hex", etc. is passed in encoding. The ECDSA public key is passed in the last argument (pubkey).
The method returns 1 for a valid signature, 0 for an invalid signature, and -1 for any other failure.