Question

我正在使用Java（jdk 1.7）和bouncycastle库来获取p7m签名文件的内容。

在构建路径中，添加了以下文件：

bcpkix-jdk15on-160.jar
commons-io-2.1.jar
log4j-1.2.17.jar
bcprov-ext-jdk15on-160.jar
bcprov-jdk15on-160.jar

这是我正在使用的代码：

public static void main(String[] args) throws Exception {
    File f = new File("E:\\test\\file.xml.p7m");

    logger.debug(f.getAbsolutePath());
    byte[] content = org.apache.commons.io.FileUtils.readFileToByteArray(f);

    byte[] contentUnsigned = removeP7MCodes(f.getName(), content);
    if (contentUnsigned != null)
        logger.debug(new String(contentUnsigned));
}

public static byte[] removeP7MCodes(final String fileName, final byte[] p7bytes) {
    try {

        if (p7bytes == null)
            return p7bytes;

        if (!fileName.toUpperCase().endsWith(".P7M")) {
            return p7bytes;
        }

        // This is where I get the exception
        CMSSignedData cms = new CMSSignedData(p7bytes); 

        if (cms.getSignedContent() == null) {
            logger.error("Unable to find signed Content during decoding from P7M for file: " + fileName);               
            return null;
        }

        ByteArrayOutputStream out = new ByteArrayOutputStream();
        cms.getSignedContent().write(out);

        return out.toByteArray();
    } catch (CMSException e) {
        logger.error("CMSException from P7M for file: " + fileName, e);
    } catch (IOException e) {
        logger.error("IOException from P7M for file: " + fileName, e);
    }
    return null;
}

对于我测试过的大多数p7m，它都可以正常工作，没有错误/问题。

有些p7m文件无法解码，并且出现以下错误（我尝试使用在线工具进行验证，并且这些文件是真实的）：

11:01:30 DEBUG [DecoderTester:45] - E:\test\file.xml.p7m
11:01:30 ERROR [DecoderTester:75] - CMSException from P7M for file: file.xml.p7m
org.bouncycastle.cms.CMSException: Malformed content.
    at org.bouncycastle.cms.CMSUtils.readContentInfo(Unknown Source)
    at org.bouncycastle.cms.CMSUtils.readContentInfo(Unknown Source)
    at org.bouncycastle.cms.CMSSignedData.<init>(Unknown Source)
    at com.decoder.DecoderTester.removeP7MCodes(DecoderTester.java:63)
    at com.decoder.DecoderTester.main(DecoderTester.java:48)
Caused by: java.lang.IllegalArgumentException: unknown object in getInstance: org.bouncycastle.asn1.DERApplicationSpecific
    at org.bouncycastle.asn1.ASN1Sequence.getInstance(Unknown Source)
    at org.bouncycastle.asn1.cms.ContentInfo.getInstance(Unknown Source)
    ... 5 more

我尝试删除以下两个库之间的一个库：bcprov-ext-jdk15on-160.jar和bcprov-jdk15on-160.jar，但出现相同的错误。

您有什么想法吗？

从P7M获取SignedContent

0 个答案: