/*
 * Message Digest (MD) and Message Authentication Code (MAC) Module
 *
 * Provides commands to calculate a message digest (MD) or message
 * authentication code (MAC) using a specified hash function and/or cipher.
 *
 * Copyright (C) 2023 Brian O'Hagan
 *
 */

#include "tlsInt.h"
#include "tclOpts.h"

 *	Sets result to message digest or an error message.
 *
 *-------------------------------------------------------------------
 */
int DigestFinalize(Tcl_Interp *interp, DigestState *statePtr, Tcl_Obj **resultObj) {
    unsigned char md_buf[EVP_MAX_MD_SIZE];
    unsigned int ulen;
    int res = 0, md_len = 0;

    dprintf("Called");

    /* Finalize cryptography function and get result */
    switch(statePtr->format & 0xFF0) {
    case TYPE_MD:
	if (!(statePtr->format & IS_XOF)) {
	    res = EVP_DigestFinal_ex(statePtr->ctx, md_buf, &ulen);
	    md_len = (int) ulen;
	} else {
	    res = EVP_DigestFinalXOF(statePtr->ctx, md_buf, (size_t) EVP_MAX_MD_SIZE);
	    md_len = EVP_MAX_MD_SIZE;

 *	TCL_OK or TCL_ERROR
 *
 * Side effects:
 *	Sets result to message digest or error message
 *
 *-------------------------------------------------------------------
 */
 #define validate_argc(objc, objv) { \
    if (objc != 2) { \
	Tcl_WrongNumArgs(interp, 1, objv, "data"); \
	return TCL_ERROR; \
    } \
}
 
int MD4ObjCmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) {
    validate_argc(objc, objv);
    return DigestDataHandler(interp, objv[1], EVP_md4(), NULL, HEX_FORMAT | TYPE_MD, NULL, NULL);
}

int MD5ObjCmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) {
    validate_argc(objc, objv);
    return DigestDataHandler(interp, objv[1], EVP_md5(), NULL, HEX_FORMAT | TYPE_MD, NULL, NULL);
}

int SHA1ObjCmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) {
    validate_argc(objc, objv);
    return DigestDataHandler(interp, objv[1], EVP_sha1(), NULL, HEX_FORMAT | TYPE_MD, NULL, NULL);
}

int SHA256ObjCmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) {
    validate_argc(objc, objv);
    return DigestDataHandler(interp, objv[1], EVP_sha256(), NULL, HEX_FORMAT | TYPE_MD, NULL, NULL);
}

int SHA512ObjCmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) {
    validate_argc(objc, objv);
    return DigestDataHandler(interp, objv[1], EVP_sha512(), NULL, HEX_FORMAT | TYPE_MD, NULL, NULL);
}

/*
 *-------------------------------------------------------------------
 *
 * Tls_DigestCommands --