OpenSSL：如何从 RFC3161 时间戳回复中提取证书和令牌状态？

Question

使用 openssl ts (https://www.openssl.org/docs/man1.1.0/man1/openssl-ts.html) I can create TS queries, replies, extract tokens from replies and verify tokens (if I have the signing certificate in DER format) of the RFC3161 format as specified here: https://www.ietf.org/rfc/rfc3161.txt

要获得令牌，我可以这样做：

openssl ts -query -digest 899ba3d9f777e2a74bdd34302bc06cb3f7a46ac1f565ee128f79fd5dab99d68b -sha256 \
| curl -s -H "Content-Type: application/timestamp-query" -H "Accept: application/timestamp-reply" --data-binary @- https://freetsa.org/tsr > response.tsr
openssl ts -reply -in response.tsr -token_out -out token.tk

我还可以使用人类可读的形式打印响应 openssl ts -reply -in response.tsr -text

为了验证令牌，我需要提供参数

-CAfile trusted_certs.pem
The name of the file containing a set of trusted self-signed CA certificates in PEM format.
The file should contain one or more certificates in PEM format.

问题 1:

为什么这只需要信任锚（=自签名）证书而不需要整个链到 TSA 证书（或者 -verify 仅适用于证书链已包含在代币)?

问题二：

-cert
The TSA is expected to include its signing certificate in the response.

如果我在第一个 openssl 调用中指定了 -cert 参数，那么 token.tk 会更长并且还包含用于签署它的证书。如何从 token.tk 中提取该证书？

问题 3:

令我惊讶的是，当我请求包含证书的响应时 token.tk 变长了（我本以为只有 response.tsr 变长，而不是令牌本身），因为规范像这样指定 TimeStampToken：

   A TimeStampToken is as follows.  It is defined as a ContentInfo
   ([CMS]) and SHALL encapsulate a signed data content type.

   TimeStampToken ::= ContentInfo
     -- contentType is id-signedData ([CMS])
     -- content is SignedData ([CMS])

   The fields of type EncapsulatedContentInfo of the SignedData
   construct have the following meanings:

   eContentType is an object identifier that uniquely specifies the
   content type.  For a time-stamp token it is defined as:

   id-ct-TSTInfo  OBJECT IDENTIFIER ::= { iso(1) member-body(2)
   us(840) rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) ct(1) 4}

   eContent is the content itself, carried as an octet string.
   The eContent SHALL be the DER-encoded value of TSTInfo.

   TSTInfo ::= SEQUENCE  {
   version                      INTEGER  { v1(1) },
   policy                       TSAPolicyId,
   messageImprint               MessageImprint,
     -- MUST have the same value as the similar field in
     -- TimeStampReq
   serialNumber                 INTEGER,
    -- Time-Stamping users MUST be ready to accommodate integers
    -- up to 160 bits.
   genTime                      GeneralizedTime,
   accuracy                     Accuracy                 OPTIONAL,
   ordering                     BOOLEAN             DEFAULT FALSE,
   nonce                        INTEGER                  OPTIONAL,
     -- MUST be present if the similar field was present
     -- in TimeStampReq.  In that case it MUST have the same value.
   tsa                          [0] GeneralName          OPTIONAL,
   extensions                   [1] IMPLICIT Extensions   OPTIONAL  }

那么，签名证书存储在哪里？是扩展名吗？或者它是 ContentType 标识符的一部分？

问题四：

如果我确实指定了 -cert 参数，我如何从 token.tk 中提取文件 token_stripped.tk，以便 token_stripped.tk 与我创建请求时的效果相同没有 -cert 参数？

问题 5:

如何从 response.tsr 中提取 PKIStatus（如链接规范中指定的那样）（最好不要先将其转换为人类可读的形式）？

Answer 1

回答我自己的问题：

Question 1:

Why does this only require the trust-anchor (=self-signed) certificate and not the whole chain down to the TSA certificate (or does -verify only work with tokens for which the certificate chain has been included in the token)?

它实际上确实需要它，但如果令牌已经包含嵌入的整个信任链，则不需要它。否则必须使用 -untrusted 参数

提供

Question 2:
-cert
The TSA is expected to include its signing certificate in the response.
If I specify the -cert parameter in the first openssl call, then token.tk will be longer and also contain the certificate that was used to sign it. How can I extract that certificate from token.tk?

以下调用提取嵌入式证书：

penssl pkcs7 -inform DER -in tokenfile.tst -print_certs -outform PEM -out certificatechain.pem

Question 3:

I'm surprised that token.tk gets longer when I request the response to include the certificates (I would have assumed only response.tsr to get longer, not the token itself

TstInfo 实际上保持相同的长度，但时间戳令牌不是 TstInfo 而是包装 CMS ContentInfo，并且证书（符合规范）作为签名属性嵌入到该 ContentInfo 对象中。

Question 4:

If I did specify the -cert parameter, how can I extract a file token_stripped.tk from token.tk, so that token_stripped.tk is the same as if I would have created the request without the -cert argument?

由于证书嵌入在签名属性中而不是未签名属性中，因此不可能从包含证书链的令牌中生成有效的剥离令牌。

Question 5:

How can I extract the PKIStatus (as specified in the linked specification) from response.tsr (optimally without first converting it to human readable form)?

除了使用 openssl cli 解析人类可读的形式外，我没有找到其他方法

OpenSSL：如何从 RFC3161 时间戳回复中提取证书和令牌状态？

OpenSSL: how to extract certificates and token status from RFC3161 timestamping reply?

openssl

timestamp

rfc3161