我编写了一个使用 Google Cloud Storage 保存图像文件的小型 Qt/С++ 应用程序。我在我的 Google API 控制台中创建了一个服务帐户客户端 ID,并尝试与 Google REST API 进行交互。但首先我需要获得一个 OAuth 授权令牌。
我已经尝试获取令牌三天了,但每次我得到同样烦人的错误:{“error”:“invalid_grant”}
我尝试按照此处的建议调整时间:invalid_grant Returned using Service Account and Google Drive API。它没有帮助。
正如本主题所建议的那样,我在 Google API 控制台中创建了另一个客户端 ID:Invalid_grant in Google Analytics。没有结果。
这是我的小类请求令牌的代码。请问谁能说我做错了什么?
#include "googlestorageuploader.h"
#include "openssl/evp.h"
#include "openssl/pem.h"
#include "openssl/bio.h"
#include "openssl/err.h"
#include "openssl/pkcs12.h"
#include <QFile>
#include <QDateTime>
#include <QNetworkAccessManager>
#include <QNetworkRequest>
#include <QSslConfiguration>
#include <QDebug>
// Just a wrapper that takes OpenSsl function 'a' and calls it.
// If 'a' returns zero the wrapper throws a string containg description
// of error occured
#define OPENSSL_FUNCTION_CALL(a) \
if (!a) \
{ \
char buffer[120]; \
ERR_error_string(ERR_get_error(), buffer); \
char s[256]; \
sprintf(s, ""#a" function call failed.\n%s", buffer); \
throw s; \
} \
// String template for standard JWT Header
const QString kJwtHeader = "{\"alg\":\"RS256\",\"typ\":\"JWT\"}";
// String template for JWT claim set
// Contains two placeholders for "exp" and "iat" keys
const QString kJwtClaimSet = "{"
"\"iss\":\"XXXXXXXXXXXX-yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy@developer.gserviceaccount.com\","
"\"scope\":\"https://www.googleapis.com/auth/devstorage.readonly\","
"\"aud\":\"https://accounts.google.com/o/oauth2/token\","
"\"exp\":%1,"
"\"iat\":%2"
"}";
// This function computes JWT signature
// 'input' is an array of bytes passed as an input
// 'privateKey' is an array of bytes that contains a private key in PKCS12 format
// (as it is in the file received from 'Google APIs Console->API Access')
// Uses OpenSSL API to create a signature using SHA256withRSA
QByteArray signWithRsaSha256(const QByteArray &input, const QByteArray &privateKey)
{
EVP_PKEY *pkey = 0;
BIO *bp = 0;
EVP_MD_CTX *ctx = 0;
const EVP_MD *sha256Md = 0;
unsigned char sig[256];
unsigned int s(0);
QByteArray out;
PKCS12 *p12 = 0;
X509 *cert= 0;
OpenSSL_add_all_ciphers();
OpenSSL_add_all_digests();
ctx = EVP_MD_CTX_create();
EVP_MD_CTX_init(ctx);
sha256Md = EVP_sha256(); // TODO: need to free
bp = BIO_new_mem_buf((void*)privateKey.data(), privateKey.size());
try {
OPENSSL_FUNCTION_CALL(EVP_SignInit(ctx, sha256Md));
OPENSSL_FUNCTION_CALL(EVP_SignUpdate(ctx, input.constData(), input.size()));
OPENSSL_FUNCTION_CALL(d2i_PKCS12_bio(bp, &p12));
OPENSSL_FUNCTION_CALL(PKCS12_parse(p12, "notasecret", &pkey, &cert, NULL));
s = EVP_PKEY_size(pkey);
OPENSSL_FUNCTION_CALL(EVP_SignFinal(ctx, sig, &s, pkey));
out.setRawData((const char *)sig, s);
}
catch (const char *s)
{
qCritical() << s;
}
EVP_MD_CTX_destroy(ctx);
BIO_free(bp);
X509_free(cert);
EVP_cleanup();
return out;
}
CGoogleStorageUploader::CGoogleStorageUploader(QObject *parent) :
QObject(parent)
{
nam_ = new QNetworkAccessManager(this);
}
// Creates and sends HTTP POST request to get an authorization token
void CGoogleStorageUploader::requestToken()
{
QNetworkRequest req(QUrl("https://accounts.google.com/o/oauth2/token"));
req.setRawHeader("Host", "accounts.google.com");
req.setRawHeader("Content-Type", "application/x-www-form-urlencoded");
req.setSslConfiguration(QSslConfiguration::defaultConfiguration());
QByteArray assertion = formJWT();
QByteArray data;
data = "grant_type=urn%3Aietf%3Aparams%3Aoauth%3Agrant-type%3Ajwt-bearer&assertion=" + assertion;
QNetworkReply *reply = nam_->post(req, data);
connect(reply, SIGNAL(finished()), SLOT(onNetworkReplyFinished()));
connect(reply, SIGNAL(sslErrors(QList<QSslError>)), SLOT(onNetworkReplySslErrors(QList<QSslError>)));
connect(reply, SIGNAL(error(QNetworkReply::NetworkError)), SLOT(onNetworkReplyError(QNetworkReply::NetworkError)));
}
// Constructs JWT
QByteArray CGoogleStorageUploader::formJWT()
{
QDateTime now = QDateTime::currentDateTime();
QDateTime utcNow = now.toUTC();
quint32 secs = utcNow.toTime_t() - 300; // adjust to Google Server time
QString claimSet = kJwtClaimSet.arg(secs + 3600).arg(secs); // fill "exp" and "iat" fields
QByteArray signature, privateKey, jwt;
QFile file (":res/pk.p12"); // copy of file received from Google API Console
if (file.open(QFile::ReadOnly))
{
privateKey = file.readAll();
QByteArray encodedHeader = kJwtHeader.toUtf8().toBase64(); // serialize to UTF8 and Base64url safe encode (https://developers.google.com/accounts/docs/OAuth2ServiceAccount#formingclaimset)
QByteArray encodedClaimSet = claimSet.toUtf8().toBase64(); // serialize to UTF8 and Base64url safe encode (https://developers.google.com/accounts/docs/OAuth2ServiceAccount#formingclaimset)
// "Sign the UTF-8 representation of the input" (https://developers.google.com/accounts/docs/OAuth2ServiceAccount#computingsignature)
signature = signWithRsaSha256(QString(encodedHeader + "." + encodedClaimSet).toUtf8(), privateKey);
QByteArray encodedSignature = signature.toBase64();
jwt = encodedHeader + "." + encodedClaimSet + "." + encodedSignature;
}
file.close();
qDebug() << jwt;
return jwt;
}
void CGoogleStorageUploader::onNetworkReplyFinished()
{
QNetworkReply *r = static_cast<QNetworkReply*>(sender());
qDebug() << "finished: " << r->readAll();
}
void CGoogleStorageUploader::onNetworkReplySslErrors(const QList<QSslError> &errs)
{
QNetworkReply *r = static_cast<QNetworkReply*>(sender());
qDebug() << "ssl errors: " << r->readAll();
r->ignoreSslErrors(errs);
}
void CGoogleStorageUploader::onNetworkReplyError(QNetworkReply::NetworkError err)
{
qDebug() << "network error: " << err;
}