Function esp_idf_svc::sys::psa_key_derivation_output_bytes

pub unsafe extern "C" fn psa_key_derivation_output_bytes(
    operation: *mut psa_key_derivation_s,
    output: *mut u8,
    output_length: usize,
) -> i32

Read some data from a key derivation operation.

This function calculates output bytes from a key derivation algorithm and return those bytes. If you view the key derivation’s output as a stream of bytes, this function destructively reads the requested number of bytes from the stream. The operation’s capacity decreases by the number of bytes read.

If this function returns an error status other than #PSA_ERROR_INSUFFICIENT_DATA, the operation enters an error state and must be aborted by calling psa_key_derivation_abort().

\param[in,out] operation The key derivation operation object to read from. \param[out] output Buffer where the output will be written. \param output_length Number of bytes to output.

\retval #PSA_SUCCESS \emptydescription \retval #PSA_ERROR_NOT_PERMITTED One of the inputs was a key whose policy didn’t allow #PSA_KEY_USAGE_DERIVE. \retval #PSA_ERROR_INSUFFICIENT_DATA The operation’s capacity was less than \p output_length bytes. Note that in this case, no output is written to the output buffer. The operation’s capacity is set to 0, thus subsequent calls to this function will not succeed, even with a smaller output buffer. \retval #PSA_ERROR_INSUFFICIENT_MEMORY \emptydescription \retval #PSA_ERROR_COMMUNICATION_FAILURE \emptydescription \retval #PSA_ERROR_HARDWARE_FAILURE \emptydescription \retval #PSA_ERROR_CORRUPTION_DETECTED \emptydescription \retval #PSA_ERROR_STORAGE_FAILURE \emptydescription \retval #PSA_ERROR_BAD_STATE The operation state is not valid (it must be active and completed all required input steps), or the library has not been previously initialized by psa_crypto_init(). It is implementation-dependent whether a failure to initialize results in this error code.