/* Copyright 2005-2006, Voltage Security, all rights reserved.
 */
#include "vibecrypto.h"
#include "environment.h"
#include "base.h"
#include "libctx.h"
#include "algobj.h"
#include "sign.h"
#include "rsa.h"
#include "rsax931.h"
#include "mpint.h"
#include "errorctx.h"

int VtAlgorithmImplRSASignVerifyX931 (
   VtAlgorithmObject *object,
   Pointer info,
   unsigned int flag
   )
{
  int status;
#if VOLT_ALIGNMENT != 1
  unsigned int pad;
#endif
  unsigned int bufferSize, offset;
  VoltAlgorithmObject *obj = (VoltAlgorithmObject *)(*object);
  VoltLibCtx *libCtx = (VoltLibCtx *)(obj->voltObject.libraryCtx);
  unsigned char *buffer = (unsigned char *)0;
  VoltSignClassCtx *ctx;
  VoltRsaSignCtx *rsaCtx;
  VOLT_DECLARE_ERROR_TYPE (errorType)
  VOLT_DECLARE_FNCT_LINE (fnctLine)

  do
  {
    /* Check the flag, it should be VOLT_ALG_SET_TYPE_FLAG.
     */
    VOLT_SET_ERROR_TYPE (errorType, VT_ERROR_TYPE_PRIMARY)
    VOLT_SET_FNCT_LINE (fnctLine)
    status = VT_ERROR_INVALID_TYPE;
    if (flag != VOLT_ALG_SET_TYPE_FLAG)
      break;

    /* Check the class of the object. It should be 0 (not yet set).
     */
    VOLT_SET_FNCT_LINE (fnctLine)
    status = VT_ERROR_INVALID_SET;
    if (obj->algClass != 0)
      break;

    /* The associated info should be a NULL pointer.
     */
    VOLT_SET_FNCT_LINE (fnctLine)
    status = VT_ERROR_INVALID_ASSOCIATED_INFO;
    if (info != (Pointer)0)
      break;

    /* Allocate space for the VoltSignClassCtx and the localCtx.
     */
    VOLT_SET_FNCT_LINE (fnctLine)
    status = VT_ERROR_MEMORY;
    bufferSize = sizeof (VoltSignClassCtx) + sizeof (VoltRsaSignCtx);
#if VOLT_ALIGNMENT != 1
    /* If the alignment is 1, there's no need to pad. If not, compute
     * the pad length.
     */
    VOLT_COMPUTE_ALIGN_PAD (VOLT_ALIGNMENT, sizeof (VoltSignClassCtx), pad)
    bufferSize += pad;
#endif
    buffer = (unsigned char *)Z2Malloc (bufferSize, 0);
    if (buffer == (unsigned char *)0)
      break;
    Z2Memset (buffer, 0, bufferSize);

    ctx = (VoltSignClassCtx *)buffer;
    offset = sizeof (VoltSignClassCtx);
#if VOLT_ALIGNMENT != 1
    offset += pad;
#endif
    rsaCtx = (VoltRsaSignCtx *)(buffer + offset);

    ctx->GetDigestObject = RSAGetDigestObject;
    ctx->Pad = X931Pad;
    ctx->Unpad = X931Unpad;
    ctx->CheckSignatureInput = RSACheckSignatureInput;
    ctx->SignData = X931RSASignData;
    ctx->VerifyData = X931RSAVerifyData;
    ctx->algorithm |= VOLT_SIGNATURE_ALG_RSA;
    ctx->localSignCtx = (Pointer)rsaCtx;
    ctx->LocalSignCtxDestroy = RSASignCtxDestroy;

    obj->algClass = VOLT_CLASS_SIGNATURE | VOLT_CLASS_VERIFY;
    obj->classCtx = (Pointer)ctx;
    obj->ClassCtxDestroy = VoltSignCtxDestroy;

    status = 0;

  } while (0);

  if (status == 0)
    return (0);

  /* If there was an error, destroy what we created but did not return.
   */
  if (buffer != (unsigned char *)0)
    Z2Free (buffer);

  VOLT_LOG_ERROR_INFO (
    0, *object, status, 0, errorType,
    (char *)0, "VtAlgorithmImplRSASignVerifyX931", fnctLine, (char *)0)

  return (status);
}