/*
 * Copyright (c) 2015, NORDUnet A/S.
 * See LICENSE for licensing information.
 */

#include <stdio.h>
#include <err.h>
#include <stdlib.h>
#include <string.h>

#include <dlfcn.h>

#include "hsmhelper.h"

void *pkcs11_library;

static CK_FUNCTION_LIST_PTR pk;

void
init(char *library_path)
{
    CK_RV result;

    pkcs11_library = dlopen(library_path, RTLD_NOW);
    CK_C_GetFunctionList C_GetFunctionList = dlsym(pkcs11_library, "C_GetFunctionList");
    result = C_GetFunctionList(&pk);
    if (result != CKR_OK) {
        errx(1, "C_GetFunctionList error: %lu", result);
    }

    result = pk->C_Initialize(NULL);
    if (result != CKR_OK) {
        errx(1, "C_Initialize error: %lu", result);
    }
}

void
finalize(CK_SLOT_ID slotID)
{
    CK_RV result;

    result = pk->C_CloseAllSessions(slotID);
    if (result != CKR_OK) {
        errx(1, "C_CloseAllSessions error: %lu", result);
    }

    result = pk->C_Finalize(NULL);
    if (result != CKR_OK) {
        errx(1, "C_Finalize error: %lu", result);
    }
}


CK_SESSION_HANDLE
open_session(CK_SLOT_ID slotID)
{
    CK_RV result;
    CK_SESSION_HANDLE hSession;

    result = pk->C_OpenSession (slotID, CKF_SERIAL_SESSION, NULL, NULL, &hSession);
    if (result != CKR_OK) {
        errx(1, "C_OpenSession error: %lu", result);
    }

    return hSession;
}

void
login(CK_SESSION_HANDLE hSession, char *pin)
{
    CK_RV result;

    result = pk->C_Login(hSession, CKU_USER, (CK_UTF8CHAR_PTR)pin, strlen(pin));
    if (result != CKR_OK) {
        errx(1, "C_Login error: %lu", result);
    }
}

CK_OBJECT_HANDLE
find_key(CK_SESSION_HANDLE hSession, CK_OBJECT_CLASS class, char *label)
{
    CK_RV result;

    CK_ATTRIBUTE template[2];
    template[0].type = CKA_CLASS;
    template[0].pValue = &class;
    template[0].ulValueLen = sizeof(class);

    template[1].type = CKA_LABEL;
    template[1].pValue = label;
    template[1].ulValueLen = strlen(label);

    CK_ULONG ulCount = 2;

    result = pk->C_FindObjectsInit(hSession,
                                   template,
                                   ulCount
        ) ;
    if (result != CKR_OK) {
        errx(1, "C_FindObjectsInit error: %lu", result);
    }

    CK_OBJECT_HANDLE hObject = 0;
    CK_ULONG ulMaxObjectCount = 1;
    CK_ULONG ulObjectCount;

    result = pk->C_FindObjects(hSession, &hObject, ulMaxObjectCount,
                               &ulObjectCount);
    if (result != CKR_OK) {
        errx(1, "C_FindObjects error: %lu", result);
    }

    if (ulObjectCount < 1) {
        errx(1, "could not find key: %s", label);
    }

    result = pk->C_FindObjectsFinal (hSession);
    if (result != CKR_OK) {
        errx(1, "C_FindObjectsFinal error: %lu", result);
    }

    return hObject;
}

void
sign(CK_SESSION_HANDLE hSession, CK_OBJECT_HANDLE hKey,
     CK_BYTE_PTR pData, CK_ULONG ulDataLen,
     CK_BYTE_PTR pSignature, CK_ULONG_PTR pulSignatureLen,
     CK_MECHANISM_TYPE mechanism_type)
{
    CK_RV result;

    CK_MECHANISM mechanism;
    mechanism.mechanism = mechanism_type;
    mechanism.pParameter = NULL;
    mechanism.ulParameterLen = 0;

    result = pk->C_SignInit(hSession,
                            &mechanism,
                            hKey);
    if (result != CKR_OK) {
        errx(1, "C_SignInit error: %lu", result);
    }

    result = pk->C_Sign(hSession,
                        pData,
                        ulDataLen,
                        pSignature,
                        pulSignatureLen);

    if (result != CKR_OK) {
        errx(1, "C_Sign error: %lu", result);
    }

}