On 2/15/13 8:52 AM, Michael StJohns wrote:
Is the "mime" variant of Base64 the correct one for this? I ask because that variant ignores
extraneous characters rather than throwing an error on decode. Also, reading the code for the Base64
implementation, it silently "fixes" the case where there are missing padding "="
characters. Neither of these seem ideal for security related processing.
Just want to point out that the latest Base64.Decoder spec has been
updated to "explicitly" says
"The Base64 padding character |'='| is accepted and interpreted as the
end of the encoded byte data, but is not required. So if the final unit
of the encoded byte data only has two or three Base64 characters
(without the corresponding padding character(s) padded), they are
decoded as if followed by padding character(s). "
So it's no longer "silently" anymore:-)
-Sherman
It may be reasonable to add a PEM variant to the Base64 code that deals with
the above.
Mike
At 08:24 AM 2/14/2013, Mark Sheppard wrote:
Hi,
as part of a refactoring of the jdk codebase to use the base64 capabilities
of java.util.Base64, the following modifications,
as per the webrev,
http://cr.openjdk.java.net/~chegar/8006182/webrev.00/
have been made to complete task JDK-8006182.
Could you oblige and review these changes, please?
Description:
jdk8 has java.util.Base64 to define a standard API for base64
encoding/decoding. It would be good to investigate whether this API could be
used in the security components, providers and regression tests.
In the main this work involved replacing the sun.misc.BASE64Encoder and
sun.misc.BASE64Decoder with the
corresponding Mime Base64 Encoder/Decoder (as per rfc2045) from the
java.util.Base64 class.
This is a like for like replacement.
As such, sun.misc.BASE64Encoder maps to the encoder returned by
java.util.Base64.getMimeEncoder()
sun.misc.BASE64Decoder maps to the decoder returned by
java.util.Base64.getMimeDecoder()
However a couple of items worth noting:
In the jarsigner (Main.java) the standard Base64 encoder (rfc 4648),
java.util.Base64.getEncoder(), has been used to replace the JarBASE64Encoder,
which was a package private extension of BASE64Encoder, which avoids writing
newline to the encoded data.
In the keytool (Main.java), methods such as dumpCert, printCert. printCRL, and
so on, write a Base64 encoding to an OutputStream, typically std out.
This is achieved in the BASE64Encoder, by passing the OutputStream to methods
such as encodeBuffer().
A couple of options exist to do this under the new Base64 utilities, which
include:
* using a Mime Encoder encodeToString() and output to the stream via println()
* use the wrap capabilities of the Base64.Encoder:
- define a package private class, which extends FilterOutputStream (e.g.
NoCloseWrapperOutputStream) and, overrides close() to do nothing
- inject the OutputStream, passed to the keytool method, into the
NoCloseWrapperOutputStreamwapper,
- wrap() the NoCloseWrapperOutputStreamwrapper in the Mime Encoder, which
will in turn return an encapsulating OutputStream;
- write the data buffer to be encoded to the encoder's OutputStream;
- close the encoder's OutputStream, which completes the base64 encoding;
- append a newline to the initial OutputStream.
pragmatics and the simplest thing that works, went for the first option.
regards
Mark
