[技术博客]阿里云签名机制字符串的C语言实现

问题描述见：阿里云签名机制

话不多说，上字符串函数转化函数代码

bool AlicloudRequest::sendV2Request() {

    if( query_parameters.find( "Action" ) == query_parameters.end() ) {

        this->errorCode = "E_INTERNAL";

        this->errorMessage = "No action specified in request.";

        dprintf( D_ALWAYS, "No action specified in request, failing.\n" );

        return false;

    }

    std::string protocol, host, httpRequestURI;

    if(! parseURL( serviceURL, protocol, host, httpRequestURI )) {

        this->errorCode = "E_INVALID_SERVICE_URL";

        this->errorMessage = "Failed to parse service URL.";

        dprintf( D_ALWAYS, "Failed to match regex against service URL '%s'.\n", serviceURL.c_str() );

        return false;

    }

    if( (protocol != "http" && protocol != "https" && protocol != "x509" && protocol != "euca3" && protocol != "euca3s" ) ) {

        this->errorCode = "E_INVALID_SERVICE_URL";

        this->errorMessage = "Service URL not of a known protocol (http[s]|x509|euca3[s]).";

        dprintf( D_ALWAYS, "Service URL '%s' not of a known protocol (http[s]|x509|euca3[s]).\n", serviceURL.c_str() );

        return false;

    }

    std::string hostAndPath = host + httpRequestURI;

    std::transform( host.begin(), host.end(), host.begin(), & tolower );

    if( httpRequestURI.empty() ) { httpRequestURI = "/"; }

    if( protocol == "euca3" || protocol == "euca3s" ) {

        query_parameters.erase( "InstanceInitiatedShutdownBehavior" );

    }

    std::string keyID;

    if( protocol != "x509" ) {

        if( ! readShortFile( this->accessKeyFile, keyID ) ) {

            this->errorCode = "E_FILE_IO";

            this->errorMessage = "Unable to read from accesskey file '" + this->accessKeyFile + "'.";

            dprintf( D_ALWAYS, "Unable to read accesskey file '%s', failing.\n", this->accessKeyFile.c_str() );

            return false;

        }

        trim( keyID );

        query_parameters.insert( std::make_pair( "AccessKeyId", keyID ) );

    }

    std::stringstream ss;

    ss<<rand();

    std::string randnum = ss.str();

    query_parameters.insert( std::make_pair( "SignatureMethod", "HMAC-SHA1" ) );

    query_parameters.insert( std::make_pair( "SignatureNonce", randnum ) );

    query_parameters.insert( std::make_pair( "SignatureVersion", "1.0" ) );

    Throttle::now( & signatureTime );

    time_t now; time( & now );

    //now+=28800;

    struct tm brokenDownTime; gmtime_r( & now, & brokenDownTime );

    char iso8601[32];

    strftime(iso8601, sizeof(iso8601), "%Y-%m-%dT%H:%M:%SZ", gmtime(&now));

    query_parameters.insert( std::make_pair( "Timestamp", iso8601 ) );

    std::string stringToSign = "POST&%2F&"

                             //+ host + "\n"

                             //+ httpRequestURI + "\n"

                             + alicloudURLEncode(canonicalQueryString);

    std::string saKey;

    if( protocol == "x509" ) {

        saKey = std::string( "not-the-DN" );

        dprintf( D_FULLDEBUG, "Using '%s' as secret key for x.509\n", saKey.c_str() );

    } else {

        if( ! readShortFile( this->secretKeyFile, saKey ) ) {

            this->errorCode = "E_FILE_IO";

            this->errorMessage = "Unable to read from secretkey file '" + this->secretKeyFile + "'.";

            dprintf( D_ALWAYS, "Unable to read secretkey file '%s', failing.\n", this->secretKeyFile.c_str() );

            return false;

        }

        trim( saKey );

    }

    unsigned int mdLength = 0;

    unsigned char messageDigest[EVP_MAX_MD_SIZE];

    const unsigned char * hmac = HMAC( EVP_sha1(), saKey.c_str(), saKey.length(),

        (const unsigned char *)stringToSign.c_str(), stringToSign.length(), messageDigest, & mdLength );

    if( hmac == NULL ) {

        this->errorCode = "E_INTERNAL";

        this->errorMessage = "Unable to calculate query signature (SHA1 HMAC).";

        dprintf( D_ALWAYS, "Unable to calculate SHA1 HMAC to sign query, failing.\n" );

        return false;

    }

    char * base64Encoded = condor_base64_encode( messageDigest, mdLength );

    std::string signatureInBase64 = base64Encoded;

    free( base64Encoded );

    std::string postURI;

    if( protocol == "x509" ) {

        postURI = "https://" + hostAndPath;

    } else if( protocol == "euca3" ) {

        postURI = "http://" + hostAndPath;

    } else if( protocol == "euca3s" ) {

        postURI = "https://" + hostAndPath;

    } else {

        postURI = this->serviceURL;

    }

    dprintf( D_FULLDEBUG, "Request URI is '%s'\n", postURI.c_str() );

    size_t index = canonicalQueryString.find( "AccessKeyId=" );

    if( index != std::string::npos ) {

        size_t skipLast = canonicalQueryString.find( "&", index + 14 );

        char swap = canonicalQueryString[ index + 15 ];

        canonicalQueryString[ index + 15 ] = '\0';

        char const * cqs = canonicalQueryString.c_str();

        if( skipLast == std::string::npos ) {

            dprintf( D_FULLDEBUG, "Post body is '%s...'\n", cqs );

        } else {

            dprintf( D_FULLDEBUG, "Post body is '%s...%s'\n", cqs, cqs + skipLast );

        }

        canonicalQueryString[ index + 15 ] = swap;

    } else {

        dprintf( D_FULLDEBUG, "Post body is '%s'\n", canonicalQueryString.c_str() );

    }

    return sendPreparedRequest( protocol, postURI, canonicalQueryString );

}