wolfssl/tests/swdev/swdev_loader.c

/* tests/swdev/swdev_loader.c -- main-side loader for wc_swdev. */

#include "swdev_loader.h"

#include <wolfssl/wolfcrypt/error-crypt.h>

#ifndef WOLF_CRYPTO_CB
#error "wc_swdev loader requires WOLF_CRYPTO_CB"
#endif

/* resolved at link time from swdev.o */
extern int wc_SwDev_Callback(int devId, wc_CryptoInfo* info, void* ctx);

/* Init always (re)registers because wolfCrypt_Cleanup wipes the cryptocb
 * table; only the final Cleanup unregisters. */
static wolfSSL_Atomic_Int swdev_refCount = WOLFSSL_ATOMIC_INITIALIZER(0);

int wc_SwDev_Init(void)
{
    int ret;

    ret = wc_CryptoCb_RegisterDevice(WC_SWDEV_ID, wc_SwDev_Callback, NULL);
    if (ret != 0)
        return ret;

#ifdef WOLF_CRYPTO_CB_FIND
    wc_CryptoCb_SetDeviceFindCb(wc_SwDev_FindCb);
#endif

    (void)wolfSSL_Atomic_Int_FetchAdd(&swdev_refCount, 1);
    return 0;
}

void wc_SwDev_Cleanup(void)
{
    int my_refCount = wolfSSL_Atomic_Int_SubFetch(&swdev_refCount, 1);

    if (my_refCount == 0) {
    #ifdef WOLF_CRYPTO_CB_FIND
        wc_CryptoCb_SetDeviceFindCb(NULL);
    #endif
        wc_CryptoCb_UnRegisterDevice(WC_SWDEV_ID);
    }
    else if (my_refCount < 0) {
        /* called more times than Init; restore floor */
        (void)wolfSSL_Atomic_Int_AddFetch(&swdev_refCount, 1);
    }
}

#ifdef WOLF_CRYPTO_CB_FIND
int wc_SwDev_FindCb(int currentId, int algoType)
{
    (void)algoType;

    /* only redirect ops with no bound device; let others pass through */
    if (currentId == INVALID_DEVID)
        return WC_SWDEV_ID;

    return currentId;
}
#endif