【发布时间】:2016-04-09 23:02:48
【问题描述】:
我知道这是一篇与其他人非常相似的帖子(例如this one),但帖子中缺少对我的情况可能很重要的细节。
首先,这是我的简化程序:
#include "stdafx.h"
#include <windows.h>
#include <wincrypt.h>
int _tmain(int argc, _TCHAR* argv[])
{
// usage: CertExtract certpath
char keyFile[] = "C:\\Certificates\\public.crt";
BYTE lp[65536];
SECURITY_ATTRIBUTES sa;
HANDLE hKeyFile;
DWORD bytes;
PCCERT_CONTEXT certContext;
sa.nLength = sizeof(sa);
sa.lpSecurityDescriptor = NULL;
sa.bInheritHandle = FALSE;
hKeyFile = CreateFile(keyFile, GENERIC_READ, FILE_SHARE_READ, &sa, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
if (hKeyFile) {
if (ReadFile(hKeyFile, lp, GetFileSize(hKeyFile, NULL), &bytes, NULL) && bytes > 0) {
certContext = CertCreateCertificateContext(X509_ASN_ENCODING, lp, bytes);
if (certContext) {
printf("yay!");
CertFreeCertificateContext(certContext);
}
else {
printf("Could not convert certificate to internal form\n");
}
}
else {
printf("Failed to read key file: %s\n", keyFile);
}
}
else {
printf("Failed to open key file: %s\n", keyFile);
}
CloseHandle(hKeyFile);
return 0;
}
为了创建证书,我对 OpenSSL 使用了以下步骤:
C:\Certificates>openssl genrsa -out private.key 1024
Loading 'screen' into random state - done
Generating RSA private key, 1024 bit long modulus
......................................++++++
................++++++
e is 65537 (0x10001)
C:\Certificates>openssl req -new -key private.key -out public.csr
Loading 'screen' into random state - done
C:\Certificates>copy private.key private.key.org
1 file(s) copied.
C:\Certificates>openssl rsa -in private.key.org -out private.key
writing RSA key
C:\Certificates>openssl x509 -req -days 365 -in public.csr -signkey private.key -ou
t public.crt
Loading 'screen' into random state - done
Signature ok
subject=/CN=My Signing Cert
Getting Private key
使用以下配置文件:
RANDFILE = .rnd
[ req ]
distinguished_name = req_distinguished_name
prompt = no
[ req_distinguished_name ]
commonName = My Signing Cert
证书文件如下:
-----BEGIN CERTIFICATE-----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=
-----END CERTIFICATE-----
将 PEM 编码转换为十六进制可以让我识别证书的各个部分:
30 SEQUENCE //Certificate
(82 01 AB)
30 SEQUENCE //tbsCertificate
(82 01 14)
02 INTEGER //serialNumber
(09)
00 D4 27 25 A4 D0 EC 65 45
30 SEQUENCE //signature
(0D)
06 OBJECT IDENTIFIER
(09)
2A 86 48 86 F7 0D 01 01 05
05 NULL
(00)
30 SEQUENCE //issuer
(1A)
31 SET
(18)
30 SEQUENCE
(16)
06 OBJECT IDENTIFIER
(03)
55 04 03
0C UTF8String
(0F)
4D 79 20 53 69 67 6E 69 6E 67 20 43 65 72 74
30 SEQUENCE //validity
(1E)
17 UTCTime
(0D)
31 36 30 31 30 35 32 32 33 38 35 39 5A
17 UTCTime
(0D)
31 37 30 31 30 34 32 32 33 38 35 39 5A
30 SEQUENCE //subjectName
(1A)
31 SET
(18)
30 SEQUENCE
(16)
06 OBJECT IDENTIFIER
(03)
55 04 03
0C UTF8String
(0F)
4D 79 20 53 69 67 6E 69 6E 67 20 43 65 72 74
30 SEQUENCE //subjectPublicKeyInfo
(81 9F)
30 SEQUENCE //algorithmId
(0D)
06 OBJECT IDENTIFIER //algorithm
(09)
2A 86 48 86 F7 0D 01 01 01
05 NULL
(00)
03 BIT STRING //subjectPublicKey
(81 8D)
[00] //padding bits
30 SEQUENCE //RSAPublicKey
(81 89)
02 INTEGER //modulus
(81 81)
00 9A 1B 22 17 D2 48 C2 C4 3D E1 BD 48 E0 5E 95 61 E8 E2 18 CA 5D EF 1D 4F A7 25 94 FA FA 41 77 57 7B 65 4D 2E 1F 5F C5 59 71 B2 95 46 15 0C 23 94 5D CE 1D 89 E6 49 09 D8 DE 6D 9B E7 09 45 35 85 6E 1E FC BC AD 4B 19 58 E1 78 76 B4 9B 8A A5 8A 87 44 EE 27 EE 0C 05 E1 AA 12 8A E6 4C 9F A4 88 6A 8D 9B 92 15 46 B4 EE F4 E5 7C 7F 45 D0 4C 65 75 A7 11 E2 AD C4 31 B0 68 71 63 9C 34 41 38 E3 02 03 01 00 01
30 SEQUENCE //signatureAlgorithm
(0D)
06 OBJECT IDENTIFIER
(09)
2A 86 48 86 F7 0D 01 01 05
05 NULL
(00)
03 BIT STRING //signatureValue
(81 81)
[00] //padding bits
79 DA A3 29 F3 32 20 50 BC 9D 46 C9 EA DF D8 F0 3F 9F 24 5C 02 71 DC 28 8D 41 62 CE BE FC 14 4C 00 21 94 9A B3 56 F5 6D 74 A4 03 E4 04 A2 85 BB A5 87 41 01 FC CD B8 3D D6 7D 90 08 66 9A 85 96 BE 2B 3C D2 2A 1F 36 1A D0 E2 1D 0C FC 33 41 02 DA DF 33 CA AA 38 FA 41 E4 D6 12 2E 7F 02 BC CE FA C4 D5 BF 89 B7 3A 0D C6 42 33 02 85 BF 07 FC 6C 6C 59 D6 C2 A2 63 D5 3F CD 83 4D 47 AD F9 95
这似乎符合X.509 specs(正如我所期望的那样):
Certificate ::= {
tbsCertificate TBSCertificate,
signatureAlgorithm AlgorithmIdentifier,
signatureValue BIT STRING
}
TBSCertificate ::= SEQUENCE {
version [0] Version DEFAULT v1, <-- what does this mean?
serialNumber INTEGER,
signature AlgorithmIdentifier,
issuer Name,
validity Validity,
subjectName Name,
subjectPublicKeyInfo SubjectPublicKeyInfo
...
}
除了版本部分的唯一例外,我不清楚它是否是可选的(尽管它似乎从未与我使用 OpenSSL 创建的证书一起添加)。
我可以打开证书以导入证书存储(并且可以成功导入存储),所以我认为文件/编码没有任何特别问题。
当我调用 CertCreateCertificateContext 时,我的 lp 缓冲区如下所示:
-----BEGIN CERTIFICATE-----\nMIIBqzCCARQCCQDUJyWk0OxlRTANBgkqhkiG9w0BAQUFADAaMRgwFgYDVQQDDA9N\neSBTaWduaW5nIENlcnQwHhcNMTYwMTA1MjIzODU5WhcNMTcwMTA0MjIzODU5WjAa\nMRgwFgYDVQQDDA9NeSBTaWduaW5nIENlcnQwgZ8wDQ...
和 bytes = 639 -- 这是文件大小。
我已尝试添加逻辑以删除证书 cmets,但 examples 以这种方式导入证书并不表示这应该是必要的。
我尝试将 dwCertEncodingType 设置为 X509_ASN_ENCODING | PKCS_7_ASN_ENCODING 和 PKCS_7_ASN_ENCODING 出于绝望(虽然我不相信我在这里使用 PKCS#7 编码...有点模糊)。
有人对我在这里可能做错了什么有任何建议吗?我很感激。
【问题讨论】:
-
CertCreateCertificateContext returns ASN1 bad tag value met 的可能重复项。证书需要进行 DER 编码(二进制),而不是 PEM 编码(带有封装边界的 Base64)。
标签: windows winapi encryption certificate cryptoapi