/* Define maximum certificate size. Max PEM size 100kB and DER size is 24kB. */
#define CERT_STR_SIZE 32768


/*
 * Binary string to hex string
 */
int String_to_Hex(char* input, int ilen, char *output, int olen) {
int String_to_Hex(unsigned char* input, int ilen, unsigned char *output, int olen) {
    int count = 0;
    unsigned char *iptr = input;
    unsigned char *optr = &output[0];
    const char *hex = "0123456789abcdef";

    for (int i = 0; i < ilen && count < olen - 1; i++, count += 2) {
	sprintf(output + count, "%02X", input[i] & 0xff);
        *optr++ = hex[(*iptr>>4)&0xF];
        *optr++ = hex[(*iptr++)&0xF];
    }
    output[count] = 0;
    *optr = 0;
    return count;
}

/*
 * BIO to Buffer
 */
int BIO_to_Buffer(int result, BIO *bio, void *buffer, int size) {