chilkat.Dh

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.

Returns the current Diffie-Hellman generator, g. The generator is the small public integer used with the prime modulus p in the modular exponentiation operations that create the public exchange value and shared secret.

For this class, g is expected to be 2 or 5. Its value is established by UseKnownPrime, GenPG, or SetPG.

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.

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.

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.

Indicates the success or failure of the most recent method call: true means success, false 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. Note: This property does not apply to methods that return integer values or to boolean-returning methods where the boolean does not indicate success or failure.

Returns the current Diffie-Hellman prime modulus, p, as a hex-encoded SSH1-format bignum. The value is established by UseKnownPrime, GenPG, or SetPG.

The modulus is a safe prime: p = 2q + 1, where q is also prime. Safe-prime groups are commonly used for finite-field Diffie-Hellman because their subgroup structure is well understood.

If set to true, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is false. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.

Version of the component/library, such as "10.1.0"

Creates this party's public Diffie-Hellman exchange value, conventionally written as E = gx mod p. Before calling this method, initialize the common Diffie-Hellman parameters by calling UseKnownPrime, GenPG, or SetPG.

num_bits (numBits) controls the size of the randomly generated private exponent retained internally by this Dh object. Chilkat recommends setting it to twice the desired strength of the symmetric key that will ultimately be derived. For example, use 256 when the protocol will derive a 128-bit key.

The returned E value is a hex-encoded SSH1-format bignum. It is public and is sent to the other party. The size of the eventual shared-secret integer is determined primarily by p; numBits does not make the returned shared secret a fixed-length symmetric key.

For language bindings where a string return cannot directly communicate failure, check LastMethodSuccess. If it is FALSE, inspect LastErrorText.

Returns the string, or nil, err on failure (or when nothing is found). The second return value, err, is the object's last_error_text; wrap the call in assert() to raise an error instead.

Computes the Diffie-Hellman shared secret from the other party's public exchange value. e is the peer's E value, encoded as the hexadecimal representation of an SSH1-format bignum.

This method must be called on the same Dh object that previously called CreateE. Both parties must also be using the same p and g parameters. Internally, the method computes K = Ex mod p, where x is the private value generated by CreateE.

The result is the shared-secret integer K, returned as a hex-encoded SSH1-format bignum. When the exchange is performed correctly, both parties compute the same value.

For language bindings where a string return cannot directly communicate failure, check LastMethodSuccess. If it is FALSE, inspect LastErrorText.

Returns the string, or nil, err on failure (or when nothing is found). The second return value, err, is the object's last_error_text; wrap the call in assert() to raise an error instead.

Generates new finite-field Diffie-Hellman parameters and stores them in this object. num_bits specifies the size of the safe prime p in bits, and g specifies the generator g, which should be 2 or 5.

On success, the generated values are available through the P and G properties. The prime generation and validation process is computationally expensive, especially for large groups.

Returns TRUE if the parameters were generated successfully; otherwise returns FALSE. Check LastErrorText for failure details.

Returns true on success, nil, err on failure. The second return value, err, is the object's last_error_text; wrap the call in assert() to raise an error instead.

Sets explicit finite-field Diffie-Hellman parameters for this object. p is the prime modulus p, supplied as a hex-encoded SSH1-format bignum, and g is the generator g, normally 2 or 5.

The method validates that the supplied values satisfy the requirements expected by this Diffie-Hellman implementation. It returns TRUE if the parameters are accepted; otherwise it returns FALSE.

Returns true on success, nil, err on failure. The second return value, err, is the object's last_error_text; wrap the call in assert() to raise an error instead.

Selects one of eight built-in safe-prime MODP groups and sets the object's P and G properties. index is a Chilkat selector from 1 through 8; it is not the IKE group number.