#include <krb5_locl.h>

RCSID("$Id$");

krb5_error_code
krb5_rd_safe(krb5_context context,
	     krb5_auth_context auth_context,
	     const krb5_data *inbuf,
	     krb5_data *outbuf,
	     /*krb5_replay_data*/ void *outdata)
{
  krb5_error_code r;
  KRB_SAFE safe;
  size_t len;

  r = decode_KRB_SAFE (inbuf->data, inbuf->length, &safe, &len);
  if (r) 
      goto failure;
  if (safe.pvno != 5) {
      r = KRB5KRB_AP_ERR_BADVERSION;
      goto failure;
  }
  if (safe.msg_type != krb_safe) {
      r = KRB5KRB_AP_ERR_MSG_TYPE;
      goto failure;
  }
  /* XXX - checksum collision-proff and keyed */
  if (safe.cksum.cksumtype != CKSUMTYPE_RSA_MD4) {
      r = KRB5KRB_AP_ERR_INAPP_CKSUM;
      goto failure;
  }

  /* check sender address */

  if (safe.safe_body.s_address
      && !krb5_address_compare (context,
				auth_context->remote_address,
				safe.safe_body.s_address)) {
      r = KRB5KRB_AP_ERR_BADADDR;
      goto failure;
  }

  /* check receiver address */

  if (safe.safe_body.r_address
      && !krb5_address_compare (context,
				auth_context->local_address,
				safe.safe_body.r_address)) {
      r = KRB5KRB_AP_ERR_BADADDR;
      goto failure;
  }

  /* check timestamp */
  if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_TIME) {
      struct timeval tv;

      gettimeofday (&tv, NULL);
      if (safe.safe_body.timestamp == NULL ||
	  safe.safe_body.usec      == NULL ||
	  *(safe.safe_body.timestamp) - tv.tv_sec > 600) {
	  r = KRB5KRB_AP_ERR_SKEW;
	  goto failure;
      }
  }
  /* XXX - check replay cache */

  /* check sequence number */
  if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) {
      if (safe.safe_body.seq_number == NULL ||
	  *safe.safe_body.seq_number != ++auth_context->remote_seqnumber) {
	  r = KRB5KRB_AP_ERR_BADORDER;
	  goto failure;
      }
  }

  r = krb5_verify_checksum (context,
			    safe.safe_body.user_data.data,
			    safe.safe_body.user_data.length,
			    &safe.cksum);
  if (r)
      goto failure;
  outbuf->length = safe.safe_body.user_data.length;
  outbuf->data   = malloc(outbuf->length);
  if (outbuf->data == NULL) {
      r = ENOMEM;
      goto failure;
  }
  memcpy (outbuf->data, safe.safe_body.user_data.data, outbuf->length);
  free_KRB_SAFE (&safe);
  return 0;
failure:
  free_KRB_SAFE (&safe);
  return r;
}