Author: Klaus Post <******@****.***>
Date:   Thu Nov 18 12:15:22 2021 -0800

    Improve performance on multiple versions (#13573)
```

- A fix must be a valid fix that was reproduced and seen in a customer environment, for example.

```
commit 886262e58af77ebc7c836ef587c08544e9a0c271
Author: Harshavardhana <******@****.***>
Date:   Wed Nov 17 15:49:12 2021 -0800

			// Verify if date headers are set, if not reject the request
			amzDate, errCode := parseAmzDateHeader(r)
			if errCode != ErrNone {
				if ok {
					tc.FuncName = "handler.Auth"
					tc.ResponseRecorder.LogErrBody = true
				}

				// All our internal APIs are sensitive towards Date
				// header, for all requests where Date header is not
				// present we will reject such clients.

	},
	ErrMalformedDate: {
		Code:           "MalformedDate",
		Description:    "Invalid date format header, expected to be in ISO8601, RFC1123 or RFC1123Z time format.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrMalformedPresignedDate: {
		Code:           "AuthorizationQueryParametersError",
		Description:    "X-Amz-Date must be in the ISO8601 Long Format \"yyyyMMdd'T'HHmmss'Z'\"",
		HTTPStatusCode: http.StatusBadRequest,

	// can reach that size according to https://aws.amazon.com/articles/1434
	maxFormFieldSize = int64(1 * humanize.MiByte)

	// The maximum allowed time difference between the incoming request
	// date and server date during signature verification.
	globalMaxSkewTime = 15 * time.Minute // 15 minutes skew allowed.

	// GlobalStaleUploadsExpiry - Expiry duration after which the uploads in multipart,
	// tmp directory are deemed stale.

	// Add the algorithm condition, only accept AWS SignV4 Sha256.
	algorithmConditionStr := `["eq", "$x-amz-algorithm", "AWS4-HMAC-SHA256"]`
	// Add the date condition, only accept the current date.
	dateConditionStr := fmt.Sprintf(`["eq", "$x-amz-date", "%s"]`, t.Format(iso8601DateFormat))
	// Add the credential string, only accept the credential passed.

		// (6) Should error if the request is not ready yet, ie X-Amz-Date is in the future.
		{
			queryParams: map[string]string{
				"X-Amz-Algorithm":      signV4Algorithm,
				"X-Amz-Date":           now.Add(1 * time.Hour).Format(iso8601Format),
				"X-Amz-Expires":        "60",
				"X-Amz-Signature":      "badsignature",
				"X-Amz-SignedHeaders":  "host;x-amz-content-sha256;x-amz-date",

	return signedHeaders, ErrNone
}

// signValues data type represents structured form of AWS Signature V4 header.
type signValues struct {
	Credential    credentialHeader
	SignedHeaders []string
	Signature     string
}

// preSignValues data type represents structured form of AWS Signature V4 query string.
type preSignValues struct {
	signValues
	Date    time.Time
	Expires time.Duration
}

      or a Contribution incorporated within the Work constitutes direct
      or contributory patent infringement, then any patent licenses
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      as of the date such litigation is filed.

   4. Redistribution. You may reproduce and distribute copies of the
      Work or Derivative Works thereof in any medium, with or without

		canonicalHeaders += "\n"
	}

	date := expires // Date is set to expires date for presign operations.
	if date == "" {
		// If expires date is empty then request header Date is used.
		date = headers.Get(xhttp.Date)
	}

	// From the Amazon docs:
	//
	// StringToSign = HTTP-Verb + "\n" +
	// 	 Content-Md5 + "\n" +
	//	 Content-Type + "\n" +
	//	 Date/Expires + "\n" +
	//	 CanonicalizedProtocolHeaders +

	region = signV4Values.Credential.scope.region

	// Extract date, if not present throw error.
	var dateStr string
	if dateStr = req.Header.Get("x-amz-date"); dateStr == "" {
		if dateStr = r.Header.Get("Date"); dateStr == "" {
			return cred, "", "", time.Time{}, ErrMissingDateHeader
		}
	}

	// Parse date header.
	var err error
	date, err = time.Parse(iso8601Format, dateStr)
	if err != nil {