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pyopenssl を使用して AC 自己署名 X509v3 CA 証明書を生成しようとしています。サブジェクト鍵識別子 (SKID) を含む keyid を持つ拡張権限鍵識別子 (AKID) を追加したいと思います。

しかし、次のコード ブロックは SKID を AKID にコピーせず、例外をスローします。

コードは次のとおりです。

import OpenSSL

key = OpenSSL.crypto.PKey()
key.generate_key(OpenSSL.crypto.TYPE_RSA, 2048)

ca = OpenSSL.crypto.X509()
ca.set_version(2)
ca.set_serial_number(1)
ca.get_subject().CN = "ca.example.com"
ca.gmtime_adj_notBefore(0)
ca.gmtime_adj_notAfter(24 * 60 * 60)
ca.set_issuer(ca.get_subject())
ca.set_pubkey(key)
ca.add_extensions([
  OpenSSL.crypto.X509Extension("basicConstraints", True,
                               "CA:TRUE, pathlen:0"),
  OpenSSL.crypto.X509Extension("keyUsage", True,
                               "keyCertSign, cRLSign"),
  OpenSSL.crypto.X509Extension("subjectKeyIdentifier", False, "hash",
                               subject=ca),
  OpenSSL.crypto.X509Extension("authorityKeyIdentifier", False, "keyid:always",issuer=ca)
  ])
ca.sign(key, "sha1")
open("MyCertificate.crt.bin", "wb").write(
            OpenSSL.crypto.dump_certificate(OpenSSL.crypto.FILETYPE_ASN1, ca))

スローされる例外は次のとおりです

Traceback (most recent call last):
  File "C:\Documents and Settings\Administrator\Desktop\Certificate\certi.py", line 21, in <module>
    OpenSSL.crypto.X509Extension("authorityKeyIdentifier", False, "keyid:always",issuer=ca)
Error: [('X509 V3 routines', 'V2I_AUTHORITY_KEYID', 'unable to get issuer keyid'), ('X509 V3 routines', 'X509V3_EXT_nconf', 'error in extension')]

コードの下の行の keyid パラメータの行から「 always 」を削除すると、

OpenSSL.crypto.X509Extension("authorityKeyIdentifier", False, "keyid",issuer=ca)

AKID keyid フィールドが空になり、以下に示すように SKID が含まれていません

          00:84:13:70:73:fe:29:61:5f:33:7d:b3:74:97:3b:
            3a:f3:11:01:7c:b8:37:a8:8c:72:81:ee:92:fd:91:
            8a:11:b3:b3:02:b4:97:d5:f8:1b:91:54:7e:15:49:
            26:6d
        Exponent: 65537 (0x10001)
X509v3 extensions:
    X509v3 Basic Constraints: critical
        CA:TRUE, pathlen:0
    X509v3 Key Usage: critical
        Certificate Sign, CRL Sign
    X509v3 Subject Key Identifier: 
        CE:D1:31:DE:CF:E3:E2:BC:6C:73:3D:55:F0:88:53:0A:F1:DC:31:14
    X509v3 Authority Key Identifier: 
        0.
Signature Algorithm: sha1WithRSAEncryption
     0b:7b:28:f6:b9:1e:6e:ec:53:6a:c5:77:db:c5:3f:5e:1d:ab:
     e5:43:73:eb:52:24:af:39:2b:aa:a3:f6:34:e1:92:4b:3b:5e:
     b6:1
4

1 に答える 1

12

It means that the CA key you are using doesn't have a subjectKeyIdentifier set.

In your example you are creating the authorityKeyIdentifier using a reference to ca which doesn't have subjectKeyIdentifier set yet.

If you change your code a to:

ca.add_extensions([
  OpenSSL.crypto.X509Extension("basicConstraints", True,
                               "CA:TRUE, pathlen:0"),
  OpenSSL.crypto.X509Extension("keyUsage", True,
                               "keyCertSign, cRLSign"),
  OpenSSL.crypto.X509Extension("subjectKeyIdentifier", False, "hash",
                               subject=ca),
  ])
ca.add_extensions([
  OpenSSL.crypto.X509Extension("authorityKeyIdentifier", False, "keyid:always",issuer=ca)
  ])

then it works.

于 2013-03-29T23:25:09.643 に答える