}

	// Extract either 'X-Amz-Content-Sha256' header or 'X-Amz-Content-Sha256' query parameter (if V4 presigned)
	// Do not verify 'X-Amz-Content-Sha256' if skipSHA256.
	var contentSHA256 []byte
	if skipSHA256 := skipContentSha256Cksum(r); !skipSHA256 && isRequestPresignedSignatureV4(r) {
		if sha256Sum, ok := r.Form[xhttp.AmzContentSha256]; ok && len(sha256Sum) > 0 {
			contentSHA256, err = hex.DecodeString(sha256Sum[0])
			if err != nil {

		if s3Error = reqSignatureV4Verify(r, globalSite.Region(), serviceS3); s3Error != ErrNone {
			writeErrorResponse(ctx, w, errorCodes.ToAPIErr(s3Error), r.URL)
			return
		}

		if !skipContentSha256Cksum(r) {
			sha256hex = getContentSha256Cksum(r, serviceS3)
		}
	}

	if err := enforceBucketQuotaHard(ctx, bucket, size); err != nil {
		writeErrorResponse(ctx, w, toAPIError(ctx, err), r.URL)
		return