RE: Separate options for document line breaks and Base64 line breaks

Hi Sean,

I took a step further and also added properties to configure line length and line separators.
https://github.com/apache/santuario-xml-security-java/pull/504

By default, encoding remains compatible with RFC2045, as before.

Best regards,
Ihor.

-----Original Message-----
From: Sean Mullan via dev <[email protected]> 
Sent: 31 березня 2025 р. 21:57
To: [email protected]; Ihor Kuzmanenko <[email protected]>
Subject: Re: Separate options for document line breaks and Base64 line breaks

I think a new system property would be a reasonable approach with a default value of false. The current org.apache.xml.security.ignoreLineBreaks system property, if set to true, should override the value of the new property.

--Sean

On 3/26/25 8:26 AM, Ihor Kuzmanenko wrote:
> Hello,
> 
> 
> I know the discussion on line endings in Base64 being canonicalized to 
> &#xD; has been hold for a while.
> 
> 
> Taking into account the /base64Binary /data type of /DigestValue/, / 
> SignatureValue /and other binary data fields and looking at the note 
> on MIME line length limit in XML Schema doc (https://www.w3.org/TR/ 
> xmlschema-2/#base64Binary <https://www.w3.org/TR/xmlschema-2/
> #base64Binary>) - it looks reasonable to avoid line breaks at all.
> 
> 
> Looking at the examples at https://www.w3.org/TR/xmldsig-core2 
> <https:// www.w3.org/TR/xmldsig-core2> and especially at the note 
> after the Example 6 
> (https://www.w3.org/TR/xmldsig-core2/#sec-ECKeyValue <https://
> www.w3.org/TR/xmldsig-core2/#sec-ECKeyValue>) I can guess that 
> deviation from RFC 2045 related to line breaks is acceptable.
> 
> 
> In Apache Santuario the only way to do this is to set the / 
> org.apache.xml.security.ignoreLineBreaks/ property, but this removes 
> all document formatting as well.
> 
> 
> My suggestion is to introduce a separate property for line breaks in 
> base64, for example /org.apache.xml.security.ignoreBase64LineBreaks/, 
> to allow getting a 'pretty-printed' XML without carriage returns in 
> Base64 in the end. We can make it compatible with existing behavior if 
> we use/ java.util.Base64.getEncoder()/ when any of these properties is set.
> 
> 
> A more flexible solution is to allow overriding of Base64.Encoder 
> implementation in the API.
> 
> 
> There was also a suggestion to set up encoding options with 
> XMLSecurityProperties, see https://issues.apache.org/jira/browse/
> SANTUARIO-525 <https://issues.apache.org/jira/browse/SANTUARIO-525>
> 
> 
> Please let me know if you find any of these options reasonable and I 
> can take care of PR preparation.
> 
> 
> Thank you.
> 
> 
> Best regards,
> 
> Ihor.
> 
>