import ru.CryptoPro.CAdES.EnvelopedSignature;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
byte[] enveloped = ...зашифрованные_данные_(binary)...
X509Certificate recipientCert = ...сертификат_получателя...
PrivateKey recipientKey = ...ключ_получателя...
ByteArrayOutputStream decryptedByteDataStream = new ByteArrayOutputStream();
EnvelopedSignature signature = new EnvelopedSignature(new ByteArrayInputStream(enveloped));
signature.decrypt(recipientCert, recipientKey, decryptedByteDataStream);
byte[] decrypted = decryptedByteDataStream.toByteArray();

    public byte[] decryptPKCS7(String keyAlias, char[] keyPass, byte[] data) throws Exception {
        Asn1BerDecodeBuffer dbuf = new Asn1BerDecodeBuffer(data);
        ContentInfo all = new ContentInfo();
        all.decode(dbuf);
        dbuf.reset();
        EnvelopedData cms = (EnvelopedData)all.content;
        new KeyTransRecipientInfo();
        if (cms.recipientInfos.elements[0].getChoiceID() == 1) {
            KeyTransRecipientInfo keyTrans = (KeyTransRecipientInfo)((KeyTransRecipientInfo)cms.recipientInfos.elements[0].getElement());
            byte[] wrapKey = keyTrans.encryptedKey.value;
            Gost28147_89_Parameters params = (Gost28147_89_Parameters)cms.encryptedContentInfo.contentEncryptionAlgorithm.parameters;
            byte[] iv = params.iv.value;
            OID cipherOID = new OID(params.encryptionParamSet.value);
            byte[] text = cms.encryptedContentInfo.encryptedContent.value;
            PrivateKey recipientKey = (PrivateKey)keyStore.getKey(keyAlias, keyPass);
            SecretKey simmKey = unwrap(wrapKey, recipientKey);
            GostCipherSpec spec = new GostCipherSpec(iv, cipherOID);
            Cipher cipher = Cipher.getInstance(CIPHER_MODE, CRYPT_PROVIDER_NAME);
            cipher.init(2, simmKey, spec, (SecureRandom)null);
            byte[] result = cipher.doFinal(text, 0, text.length);
            return result;
        } else {
            throw new Exception("Unknown recipient info");
        }
    }

    private  SecretKey unwrap(byte[] wrappedKey, Key recipientKey) throws Exception {
        GostR3410_KeyTransport keyTransport = new GostR3410_KeyTransport();
        Asn1BerDecodeBuffer decoder = new Asn1BerDecodeBuffer(wrappedKey);
        keyTransport.decode(decoder);
        byte[] wrappedKeyBytes = keyTransport.sessionEncryptedKey.encryptedKey.value;
        byte[] imita = keyTransport.sessionEncryptedKey.macKey.value;
        Asn1BerEncodeBuffer encoder = new Asn1BerEncodeBuffer();
        Gost28147_89_EncryptedKey encryptedKey = new Gost28147_89_EncryptedKey(
                new Gost28147_89_Key(wrappedKeyBytes), (Gost28147_89_Key)null, new Gost28147_89_MAC(imita));
        encryptedKey.encode(encoder);
        byte[] wrapped = encoder.getMsgCopy();
        encoder.reset();

        keyTransport.transportParameters.ephemeralPublicKey.encode(encoder);

        byte[] encodedPublic = encoder.getMsgCopy();
        GostPublicKey publicKey = new GostPublicKey(encodedPublic, false);

        IvParameterSpec iv = new IvParameterSpec(keyTransport.transportParameters.ukm.value);

        OID oid = new OID(keyTransport.transportParameters.encryptionParamSet.value);
        CryptParamsSpec uz = CryptParamsSpec.getInstance(oid);
        GostCipherSpec params = new GostCipherSpec(iv, uz);

        KeyAgreement ka = KeyAgreement.getInstance(recipientKey.getAlgorithm(), CRYPT_PROVIDER_NAME);
        ka.init(recipientKey, iv);
        ka.doPhase(publicKey, true);
        SecretKey dh = ka.generateSecret(SEC_KEY_ALG_NAME);
        Cipher cipher = Cipher.getInstance(SEC_KEY_ALG_NAME, CRYPT_PROVIDER_NAME);
        cipher.init(Cipher.UNWRAP_MODE, dh, params);
        return (SecretKey)cipher.unwrap(wrapped, (String)null, Cipher.SECRET_KEY);
    }

    /** @deprecated */
    public static void CMSVerify(byte[] var0, Certificate[] var1, byte[] var2) throws Exception {
        CMSVerifyEx(var0, var1, var2, "1.2.643.2.2.9", "GOST3411", "GOST3411withGOST3410EL", "JCP");
    }

private static boolean verifyOnCert(X509Certificate var0, SignerInfo var1, byte[] var2, OID var3, boolean var4, String var5, String var6, String var7) throws Exception {