KeyUsage不允许数字签名

Question

我正在尝试从我的Java EE程序向需要证书身份验证的主机发送HTTPS请求.我有一个正确的密钥库文件,信任库和导入的CA,两个列表都显示证书在里面.

但是我收到以下错误:

javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: KeyUsage does not allow digital signatures
    at ...

...

Caused by: sun.security.validator.ValidatorException: KeyUsage does not allow digital signatures
    at sun.security.validator.EndEntityChecker.checkTLSServer(EndEntityChecker.java:270)
    at sun.security.validator.EndEntityChecker.check(EndEntityChecker.java:141)
    at sun.security.validator.Validator.validate(Validator.java:264)
    at sun.security.ssl.X509TrustManagerImpl.validate(X509TrustManagerImpl.java:326)
    at sun.security.ssl.X509TrustManagerImpl.checkTrusted(X509TrustManagerImpl.java:231)
    at     sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java:126)
at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1319)
... 29 more

在扩展部分中查看证书内容我看到以下内容:

Extensions:

#1: ObjectId: 2.5.29.14 Criticality=false
SubjectKeyIdentifier [
KeyIdentifier [
0000: 33 87 72 1D 09 2F DF FF   1A A7 D1 C0 E1 CF C5 FA  3.r../..........
0010: A4 19 54 2E                                        ..T.
]
]

#2: ObjectId: 2.16.840.1.113730.1.1 Criticality=false
NetscapeCertType [
   SSL client
]

#3: ObjectId: 2.5.29.35 Criticality=false
AuthorityKeyIdentifier [
KeyIdentifier [
0000: 74 9F 43 07 CC 75 FA D3   D0 13 0F 65 36 CC 4A 9A  t.C..u.....e6.J.
0010: E0 8E 9C 52                                        ...R
]
]

#4: ObjectId: 2.5.29.31 Criticality=false
CRLDistributionPoints [
  [DistributionPoint:
     [URIName: http://test.az:7447/Test%20CA.crl]
]]

#5: ObjectId: 2.5.29.15 Criticality=true
KeyUsage [
  DigitalSignature
]

所以我的证书确实包含KeyUsage [DigitalSignature]

抛出异常的地方的代码片段如下所示:

private final static int KU_SIGNATURE = 0;

...

private void checkTLSServer(X509Certificate cert, String parameter)
        throws CertificateException {
    Set<String> exts = getCriticalExtensions(cert);

    ...

    } else if (KU_SERVER_SIGNATURE.contains(parameter)) {
        if (checkKeyUsage(cert, KU_SIGNATURE) == false) {
            throw new ValidatorException
                    ("KeyUsage does not allow digital signatures",
                    ValidatorException.T_EE_EXTENSIONS, cert);
        }
    }

    ...
}

和checkKeyUsage函数:

private boolean checkKeyUsage(X509Certificate cert, int bit)
        throws CertificateException {
    boolean[] keyUsage = cert.getKeyUsage();
    if (keyUsage == null) {
        return true;
    }
    return (keyUsage.length > bit) && keyUsage[bit];
}

它失败了(keyUsage.length> bit)&& keyUsage [bit];

问题是为什么上面的表达式的结果= false？当bit = 0且cert.getKeyUsage()必须返回一个boolean数组[true,false,false,false,false,false,false,false,false]

Answer 1

该错误实际上来自验证服务器的证书.该证书的密钥用法部分不包含digitalSignature位.

一些密码套件需要数字签名位,特别是Diffie-Hellman密钥交换(DHE_RSA和ECDHE_RSA).您可以通过避免这些密码类型来避免此错误.否则服务器证书需要支持它.