C++ fromHex函数代码示例

static QByteArray parsePercentEncoding(const QByteArray &in)
{
	QByteArray out;

	for(int n = 0; n < in.size(); ++n)
	{
		char c = in[n];

		if(c == '%')
		{
			if(n + 2 >= in.size())
				return QByteArray();

			int hi = fromHex(in[n + 1]);
			if(hi == -1)
				return QByteArray();

			int lo = fromHex(in[n + 2]);
			if(lo == -1)
				return QByteArray();

			unsigned char val = (hi << 4) + lo;
			out += val;

			n += 2; // adjust position
		}
		else
			out += c;
	}

	return out;
}

byte * GetCBOREncoding(const cn_cbor * pControl, int * pcbEncoded)
{
	const cn_cbor * pOutputs = cn_cbor_mapget_string(pControl, "output");
	const cn_cbor * pCBOR;
	byte * pb = NULL;
	const byte * pb2;
	int i;

	if ((pOutputs == NULL) || (pOutputs->type != CN_CBOR_MAP)) {
		fprintf(stderr, "Invalid output\n");
		exit(1);
	}

	pCBOR = cn_cbor_mapget_string(pOutputs, "cbor");
	if ((pCBOR == NULL) || (pCBOR->type != CN_CBOR_TEXT)) {
		fprintf(stderr, "Invalid cbor object");
		exit(1);
	}

	pb = malloc(pCBOR->length / 2);
	pb2 = pCBOR->v.bytes;

	for (i = 0; i < pCBOR->length; i += 2) {
		pb[i / 2] = fromHex(pb2[i]) * 16 + fromHex(pb2[i + 1]);
	}

	*pcbEncoded = (int) (pCBOR->length / 2);
	return pb;
}

std::string CEncrypt::urlDecode(std::string strVal)
{
    const char *pszVal = strVal.c_str();
    std::string strTemp = "";
    size_t iLens = strVal.size();  

    for (size_t i = 0; i < iLens; i++)  
    {  
        if ('+' == pszVal[i]) 
        {
            strTemp += ' ';  
        }
        else if ('%' == pszVal[i])  
        {
            assert(i + 2 < iLens);

            unsigned char cHigh = fromHex((unsigned char)pszVal[++i]);  
            unsigned char cLow = fromHex((unsigned char)pszVal[++i]); 

            strTemp += cHigh*16 + cLow;
        }  
        else 
        {
            strTemp += pszVal[i];  
        }
    }

    return strTemp;  
}

static bool check(
    bool          ok,
    const uint8_t *rmdHex,
    const uint8_t *dataHex
) {
    uint8_t rmd[kRIPEMD160ByteSize];
    fromHex(rmd, rmdHex, kRIPEMD160ByteSize, false);

    uint8_t data[1024];
    auto dataLen = strlen((const char*)dataHex)/2;
    if(0<dataLen) {
        fromHex(data, dataHex, dataLen, false);
    }

    uint8_t cmp[kRIPEMD160ByteSize];
    rmd160(cmp, data, dataLen);

    TEST_CHECK(
        ok,
        0==memcmp(cmp, rmd, sizeof(rmd)),
        "RIPEMD-160 fails for %s\n",
        dataHex
    );
    return ok;
}

static void readVector(char * pszVec, 
   unsigned int cbVec, octet * pabVec)
{
   unsigned int i = cbVec;
   memset(pabVec, 0, cbVec);
   for ( ; i && pszVec[0] && pszVec[1]; pszVec += 2, pabVec++, i--) {
      *pabVec = (fromHex(pszVec[0]) << 4) | fromHex(pszVec[1]);
   }
   if (!i && *pszVec) printUsage(1);
}

	bool Color::fromString(const string &str)
	{
		if(str.length() != 4 && str.length() != 7)
			return false;

		if(str[0] != '#') return false;
		for(string::size_type i = 1; i < str.length(); ++i) {
			if(!isxdigit((int)str[i]))
				return false;
		}

		if(str.length() == 7) {
			m_red   = (__uint8)( (fromHex(str[1]) << 4) + fromHex(str[2]) );
			m_green = (__uint8)( (fromHex(str[3]) << 4) + fromHex(str[4]) );
			m_blue  = (__uint8)( (fromHex(str[5]) << 4) + fromHex(str[6]) );

		} else {
			__uint8 v = fromHex(str[1]);
			m_red = (__uint8)( (v << 4) + v );

			v = fromHex(str[2]);
			m_green = (__uint8)( (v << 4) + v );

			v = fromHex(str[3]);
			m_blue = (__uint8)( (v << 4) + v );
		}

		m_alpha = 255;

		return true;
	}

byte * FromHex(const char * rgch, int cch)
{
	byte * pb = malloc(cch / 2);
	const char * pb2 = rgch;
	int i;

	for (i = 0; i < cch; i += 2) {
		pb[i / 2] = fromHex(pb2[i]) * 16 + fromHex(pb2[i + 1]);
	}

	return pb;
}

Bytes hex_decode(const String& string)
{
    Bytes ret;
    ret.reserve(string.length()/2);
    
    for (auto i: range(0, (string.length()/2)*2, 2))
    {
        if (!isHex(string[i]) || !isHex(string[i+1])) break;
        ret.push_back((fromHex(string[i]) << 4) | fromHex(string[i+1]));
    }
    return ret;
}

Derived Id<n, Derived>::FromString(const String& string)
{
	if(string.length() != n * 2)
		THROW(String("Wrong length of id string for ") + typeid(Derived).name());

	Derived id;

	for(int i = 0; i < n; ++i)
		id.data[i] = (fromHex(string[i * 2]) << 4) | fromHex(string[i * 2 + 1]);

	return id;
}

bool WPUtils::crypt(bool isEncrypt, const QByteArray & in,
		QByteArray & out) {
	QByteArray key, iv;
	QString fail;

	if (!fromHex(_key, key)) {
		fail += "Key is not valid hex. ";
	}
	if (!fromHex(_iv, iv)) {
		fail += "IV is not valid hex. ";
	}

	if (!fail.isEmpty()) {
		qDebug() << "fail = " << fail;
		//toast(fail);
		return false;
	}

	AESParams params(globalContext);
	if (!params.isValid()) {
		//toast(
		qDebug () << "fails = " << QString("Could not create params. %1").arg(SBError::getErrorText(params.lastError()));
		return false;
	}

	AESKey aesKey(params, key);
	if (!aesKey.isValid()) {
		qDebug() << "failes = " <<  QString("Could not create a key. %1").arg(SBError::getErrorText(aesKey.lastError()));
		return false;
	}

	int rc;
	if (isEncrypt) {
		rc = hu_AESEncryptMsg(params.aesParams(), aesKey.aesKey(), iv.length(),
				(const unsigned char*) iv.constData(), in.length(),
				(const unsigned char *) in.constData(),
				(unsigned char *) out.data(), globalContext.ctx());
	} else {
		rc = hu_AESDecryptMsg(params.aesParams(), aesKey.aesKey(), iv.length(),
				(const unsigned char*) iv.constData(), in.length(),
				(const unsigned char *) in.constData(),
				(unsigned char *) out.data(), globalContext.ctx());
	}
	if (rc == SB_SUCCESS) {
		return true;
	}

	//toast
	qDebug() << QString("Crypto operation failed. %1").arg(SBError::getErrorText(rc));
	return false;

}

QColor convertColorFromString(const QString &s)
{
    if (s.length() == 9 && s.startsWith(QLatin1Char('#'))) {
        uchar a = fromHex(s, 1);
        uchar r = fromHex(s, 3);
        uchar g = fromHex(s, 5);
        uchar b = fromHex(s, 7);
        return QColor(r, g, b, a);
    } else {
        QColor rv(s);
        return rv;
    }
}

QColor QDeclarativeStringConverters::colorFromString(const QString &s, bool *ok)
{
    if (s.length() == 9 && s.startsWith(QLatin1Char('#'))) {
        uchar a = fromHex(s, 1);
        uchar r = fromHex(s, 3);
        uchar g = fromHex(s, 5);
        uchar b = fromHex(s, 7);
        if (ok) *ok = true;
        return QColor(r, g, b, a);
    } else {
        QColor rv(s);
        if (ok) *ok = rv.isValid();
        return rv;
    }
}

uint32_t ReadPrefHex(const char* pref_key)
{
	LoadConfigFile();
	std::string pref = "preferences:";
	pref.append(pref_key);
	return fromHex(iniparser_getstring(preferences, pref.c_str(), 0));
}

void CiscoSecret7::transform(const QByteArray &input, QByteArray &output)
{
    if (wayValue == INBOUND) {
        QByteArray data;

        cipher(seed,input, data);
        output = data.toHex().prepend(QByteArray::number(seed));

    } else {
        QByteArray encrypted = input.toUpper();

        if (encrypted.isEmpty())
            return;

        if (encrypted.size() < 3) {
            emit error(tr("Invalid hash (far too small)"),id);
            return;
        }
        bool k = true;
        seed = encrypted.mid(0,2).toInt(&k);
        if (!k || seed > MAXSEED) {
            emit error(tr("Invalid seed, it must be an unsigned integer <= %1").arg(MAXSEED),id);
            return;
        }

        QByteArray data = encrypted.mid(2);
        data = fromHex(data);
        cipher(seed,data,output);
    }
}

static bool testAddr2Hash(
    const uint8_t *addr,
    const uint8_t *hexHash
) {

    uint8_t result[kRIPEMD160ByteSize];
    auto ok = addrToHash160(result, addr, true);
    TEST_CHECK(ok, ok, "failed to decode address %s", addr);

    uint8_t hash[kRIPEMD160ByteSize];
    fromHex(hash, (const uint8_t*)hexHash, kRIPEMD160ByteSize, false);

    uint8_t hexResult[1 + 2*kRIPEMD160ByteSize];
    toHex(hexResult, result, kRIPEMD160ByteSize, false);

    TEST_CHECK(
        ok,
        0==memcmp(result, hash, kRIPEMD160ByteSize),
        "decode fail\n"
        "    for addr: %s\n"
        "    expected: %s\n"
        "         got: %s\n"
        "\n",
        addr,
        hexHash,
        hexResult
    );
    return ok;
}