Question

我想为我的存储桶中的对象创建一个预先指定的URL。我使用以下python代码：

    client = boto3.client(
    's3',
    aws_access_key_id=os.environ['AWS_ACCESS_KEY'],
    aws_secret_access_key=os.environ['AWS_SECRETS_KEY'],
    config=botocore.client.Config(signature_version='s3v4'),
    region_name='eu-central-1'
)
url = client.generate_presigned_url(
    ClientMethod='get_object',
    ExpiresIn=60,
    Params={
        'Bucket': MYBUCKET,
        'Key': MYKEY
    })

然后我将生成的URL发送到我的前端。在客户端上，我将使用生成的链接创建一个标记，并在其上使用click（）方法。这在其他项目中运行良好，但在这里我只得到错误：

The request signature we calculated does not match the signature you provided. Check your key and signing method.

这很奇怪。用户应具有所有必要的权利。因为列出我的存储桶中的所有文件都可以正常工作。

有人能指出我正确的方向，为什么这不起作用？

修改

如果这有帮助的话，我在前端使用next.js。

Answer 1

问题是boto3的版本。

我尝试了最新版本（boto3 1.7.14），产生了上述错误。

与1.6.6版本完全一样。

Answer 2

有完全相同的问题。研究了AWS文档并亲自编写了（签名v4）过程。以下基于

https://docs.aws.amazon.com/AmazonS3/latest/API/sigv4-query-string-auth.html

并且完美运行。

ENCODING = 'utf8'
SEVEN_DAYS = 604800
logger = logging.getLogger()
logger.setLevel(logging.INFO)


def sign(key, msg):
    return hmac.new(key, msg.encode(ENCODING), hashlib.sha256).digest()


def get_signature_key(key, dateStamp, regionName, serviceName):
    kDate = sign(('AWS4' + key).encode(ENCODING), dateStamp)
    kRegion = sign(kDate, regionName)
    kService = sign(kRegion, serviceName)
    kSigning = sign(kService, 'aws4_request')
    return kSigning


def generate_presigned_s3_get(bucket, object_key, region, expires_in, access_key, secret_key):
    METHOD = 'GET'
    SERVICE = 's3'
    host = bucket + '.s3.' + region + '.amazonaws.com'
    endpoint = 'https://' + host
    t = datetime.datetime.utcnow()
    amz_date = t.strftime('%Y%m%dT%H%M%SZ')
    datestamp = t.strftime('%Y%m%d')
    canonical_uri = '/' + object_key
    canonical_headers = 'host:' + host + '\n'
    signed_headers = 'host'
    algorithm = 'AWS4-HMAC-SHA256'
    credential_scope = datestamp + '/' + region + '/' + SERVICE + '/' + 'aws4_request'
    canonical_querystring = '?X-Amz-Algorithm=AWS4-HMAC-SHA256'
    canonical_querystring += '&X-Amz-Credential=' + urllib.parse.quote_plus(access_key + '/' + credential_scope)
    canonical_querystring += '&X-Amz-Date=' + amz_date
    canonical_querystring += '&X-Amz-Expires=' + str(expires_in)
    canonical_querystring += '&X-Amz-SignedHeaders=' + signed_headers
    canonical_request = METHOD + '\n' + canonical_uri + '\n' + canonical_querystring[1:] + '\n' + canonical_headers + '\n' + signed_headers + '\nUNSIGNED-PAYLOAD'
    string_to_sign = algorithm + '\n' + amz_date + '\n' + credential_scope + '\n' + hashlib.sha256(canonical_request.encode(ENCODING)).hexdigest()
    signing_key = get_signature_key(secret_key, datestamp, region, SERVICE)
    signature = hmac.new(signing_key, (string_to_sign).encode("utf-8"), hashlib.sha256).hexdigest()
    canonical_querystring += '&X-Amz-Signature=' + signature
    url = endpoint + canonical_uri + canonical_querystring
    logger.info('presigned url: %s' % url)
    return url

我也向boto3偷窥报告了此问题： https://github.com/boto/boto3/issues/1644

AWS S3使用boto3预分配网址 - 签名不匹配

2 个答案: