问题
As it turned out in the comments to this SO-question the source of the problem lies elsewhere so I decided to ask a new question.
I request a certificate from our PKI for a ecc keypair (curve is brainpoolP384r1). This is done via registration authority that does the proof of possession. After that I attach the private key to the issued certificate using some of the code in this helpful questions/answers: generate-certificate-using-ecdsa-in-c-sharp and translating-elliptic-curve-parameters-bc-to-ms.
After that I store the certificate with the private key in the MY-Store. So far everything works and the certificate is shown as valid in the MMC console.
But if I look at it with certutil -user -store my it results in the following error (unfortunately it is in german but I will explain the errors below):
Seriennummer: 4cce6787580be9db
Aussteller: C=DE, O=TestIt, CN=ManagementCA
Nicht vor: 01.03.2018 08:30
Nicht nach: 29.02.2020 08:30
Antragsteller: CN=test@my.domain
Kein Stammzertifikat
Zertifikathash(sha1): 3cd94f55fa6d1c66eff9ed1cc45649006ac12616
Schlüsselcontainer = {5C4E984A-D2DB-4BE5-BD82-7A6826C4A389}
Eindeutiger Containername: 28083d7c2cef0143c31de128e470b486_6097f4ab-4eeb-4550-91e6-2c748bfb85d3
Anbieter = Microsoft Software Key Storage Provider
Der private Schlüssel eignet sich nicht zum Nur-Text-Export.
Öffentlicher Schlüssel des Zertifikats:
Version: 3
Öffentlicher Schlüssel-Algorithmus:
Algorithmus Objekt-ID: 1.2.840.10045.2.1 ECC
Algorithmusparameter:
0000 30 82 01 40 02 01 01 30 3c 06 07 2a 86 48 ce 3d
0010 01 01 02 31 00 8c b9 1e 82 a3 38 6d 28 0f 5d 6f
0020 7e 50 e6 41 df 15 2f 71 09 ed 54 56 b4 12 b1 da
0030 19 7f b7 11 23 ac d3 a7 29 90 1d 1a 71 87 47 00
0040 13 31 07 ec 53 30 64 04 30 7b c3 82 c6 3d 8c 15
0050 0c 3c 72 08 0a ce 05 af a0 c2 be a2 8e 4f b2 27
0060 87 13 91 65 ef ba 91 f9 0f 8a a5 81 4a 50 3a d4
0070 eb 04 a8 c7 dd 22 ce 28 26 04 30 04 a8 c7 dd 22
0080 ce 28 26 8b 39 b5 54 16 f0 44 7c 2f b7 7d e1 07
0090 dc d2 a6 2e 88 0e a5 3e eb 62 d5 7c b4 39 02 95
00a0 db c9 94 3a b7 86 96 fa 50 4c 11 04 61 04 1d 1c
00b0 64 f0 68 cf 45 ff a2 a6 3a 81 b7 c1 3f 6b 88 47
00c0 a3 e7 7e f1 4f e3 db 7f ca fe 0c bd 10 e8 e8 26
00d0 e0 34 36 d6 46 aa ef 87 b2 e2 47 d4 af 1e 8a be
00e0 1d 75 20 f9 c2 a4 5c b1 eb 8e 95 cf d5 52 62 b7
00f0 0b 29 fe ec 58 64 e1 9c 05 4f f9 91 29 28 0e 46
0100 46 21 77 91 81 11 42 82 03 41 26 3c 53 15 02 31
0110 00 8c b9 1e 82 a3 38 6d 28 0f 5d 6f 7e 50 e6 41
0120 df 15 2f 71 09 ed 54 56 b3 1f 16 6e 6c ac 04 25
0130 a7 cf 3a b6 af 6b 7f c3 10 3b 88 32 02 e9 04 65
0140 65 02 01 01
Länge des öffentlichen Schlüssels: 384 Bits
Öffentlicher Schlüssel: Nicht verwendete Bits = 0
0000 04 0e e2 21 a3 24 11 58 28 f9 12 fe 7a 2d 26 5f
0010 ad 90 cc 79 1c b6 68 3a b0 ff f2 df 68 17 84 cd
0020 5f a7 9e 27 10 00 ea 6a 47 d2 74 9f c4 15 36 d1
0030 98 5e 65 5b 2e 7e 61 d4 16 85 ed 3f 24 6b c1 2c
0040 ef 48 b2 26 77 2b c3 61 05 44 e3 1c 2a 31 cb c1
0050 f6 e1 cc a2 d6 3e d8 ac 36 8f ea e7 df 7d b0 9d
0060 9d
Schlüssel-ID-Hash(rfc-sha1): e90f7f6c93e660db6742585d6dd5327f08e2469b
Schlüssel-ID-Hash(sha1): 1a0440ec89a6b951169c97d7d766c477c5a9128d
Schlüssel-ID-Hash(bcrypt-sha1): 66a3af2d30d59c36337fcf153693e6bc0111c14b
Schlüssel-ID-Hash(bcrypt-sha256): cfdf5d9b466f595f9c23dec4430a19b5134f41c882bea709ab120ed1c2496ce9
Container des öffentlichen Schlüssels:
Öffentlicher Schlüssel-Algorithmus:
Algorithmus Objekt-ID: 1.2.840.10045.2.1 ECC
Algorithmusparameter:
06 09 2b 24 03 03 02 08 01 01 0b
1.3.36.3.3.2.8.1.1.11 brainpoolP384r1
Länge des öffentlichen Schlüssels: 384 Bits
Öffentlicher Schlüssel: Nicht verwendete Bits = 0
0000 04 0e e2 21 a3 24 11 58 28 f9 12 fe 7a 2d 26 5f
0010 ad 90 cc 79 1c b6 68 3a b0 ff f2 df 68 17 84 cd
0020 5f a7 9e 27 10 00 ea 6a 47 d2 74 9f c4 15 36 d1
0030 98 5e 65 5b 2e 7e 61 d4 16 85 ed 3f 24 6b c1 2c
0040 ef 48 b2 26 77 2b c3 61 05 44 e3 1c 2a 31 cb c1
0050 f6 e1 cc a2 d6 3e d8 ac 36 8f ea e7 df 7d b0 9d
0060 9d
Schlüssel-ID-Hash(rfc-sha1): e90f7f6c93e660db6742585d6dd5327f08e2469b
Schlüssel-ID-Hash(sha1): 79d60ac0a75a30e1ba3f07ccc4dbace00610696c
Schlüssel-ID-Hash(bcrypt-sha1): 66a3af2d30d59c36337fcf153693e6bc0111c14b
Schlüssel-ID-Hash(bcrypt-sha256): cfdf5d9b466f595f9c23dec4430a19b5134f41c882bea709ab120ed1c2496ce9
FEHLER: Öffentlicher Schlüssel stimmt nicht mit gespeichertem Schlüsselsatz überein.
Das Testen der Signatur ist fehlgeschlagen.
The last part translates as:
ERROR: Certificate public key does NOT match stored keyset
Signature test FAILED
You can see that the public key itself is identical, just the AlgorithmIdentifier is different. I do not know where the container public key comes from, the certification request matches the AlgorithmIdentifier from the certificate public key shown above.
If I try to create the csr with the AlgorithmIdentifier of the container public key shown above, I get an error in the PKI "encoded key spec not recognized".
All this leeds me to the conclusion that I am doing something wrong with the csr.
I will not post the whole code as it spawns mutliple classes just the part wher the SubjectPublicKeyInfo is constructed as this seems to be the part where things go wrong:
Code that creates valid ASN1 but results in the error above (Signature test failed)
byte[] publicKey = ecPublicKeyParameters.Q.GetEncoded();
string base64PublicKey = Convert.ToBase64String(publicKey);
// This base64PublicKey is send to the server, that handles it with the code below:
var ecPars = TeleTrusTNamedCurves.GetByName("brainpoolP384r1");
ECDomainParameters ecDomPars = new ECDomainParameters(
ecPars.Curve,
ecPars.G,
ecPars.N,
ecPars.H,
ecPars.GetSeed());
var curve = ecDomPars.Curve;
byte[] data = Convert.FromBase64String(base64PublicKey);
var ecPoint = curve.DecodePoint(data);
ECPublicKeyParameters publicKey = new ECPublicKeyParameters(ecPoint, ecDomPars);
SubjectPublicKeyInfo publicKeyInfo = SubjectPublicKeyInfoFactory.CreateSubjectPublicKeyInfo(ecPublicKeyParameters);
Code that creates valid ASN1 that makes the PKI complain:
// Using ECDsaCng directly in the hope that the certificate will be valid for windows:
ECParameters ecParams = ecdsaPair.ExportParameters(false);
ECPoint ecPoint = ecParams.Q;
IEnumerable<byte> blobBytes = ecPoint.X.Concat(ecPoint.Y);
byte[] eccblob = blobBytes.ToArray();
// Sending this to the server where it will be used for SubjectPublicKeyInfo
AlgorithmIdentifier algorithmIdentifier = new AlgorithmIdentifier(new DerObjectIdentifier("1.2.840.10045.2.1"), new DerObjectIdentifier("1.3.36.3.3.2.8.1.1.11"));
SubjectPublicKeyInfo publicKeyInfo = new SubjectPublicKeyInfo(algorithmIdentifier, new DerBitString(eccblob));
How can I create a valid SubjectPublicKeyInfo that satisfies the PKI and the certutil validation?
回答1:
The problem with the cert-as-created seems to be that the certificate uses explicit curve domain parameters (which the RFCs frown on), and the private key did curve normalization to get back to a named curve, which you seem to have identified given the second approach.
In your "more manual" approach you didn't encode the public key correctly, you need a leading 04 to indicate that you're sending an uncompressed coordinate pair. (04 [x coordinate] [y coordinate]). The CA likely rejected your request because it didn't understand it.
04 0e e2 21 a3 24 11 58 28 f9 12 fe 7a 2d 26 5f
ad 90 cc 79 1c b6 68 3a b0 ff f2 df 68 17 84 cd
5f a7 9e 27 10 00 ea 6a 47 d2 74 9f c4 15 36 d1
98 5e 65 5b 2e 7e 61 d4 16 85 ed 3f 24 6b c1 2c
ef 48 b2 26 77 2b c3 61 05 44 e3 1c 2a 31 cb c1
f6 e1 cc a2 d6 3e d8 ac 36 8f ea e7 df 7d b0 9d
9d
Note the leading 04, and how it has odd length
FWIW: If you're on .NET Core 2.0 you can do this without BouncyCastle via System.Security.Cryptography.X509Certificates.CertificateRequest. That class is also available in the 4.7.2 early access release.
来源：https://stackoverflow.com/questions/49045873/c-sharp-ecc-certificate-requested-with-bouncycastle-seems-to-be-invalid-in-ne