Parsing certain images fails.

[henrythemouse]

I'm getting parsing errors that seemed to be linked to the syntax of the images in the vcard. Out of 6 images that I've checked (from vcards that were retrieved from a davical server using vdirsyncer) four failed to parse and two parsed without any issue. I discovered this when using khard to search the vcf files. I originally reported this to the khard developer on his github page. He reviewed the issue and suggested that I report it here as he suspects it's an issue with vobject. The two syntaxs are as follows:

FAILS: PHOTO;ENCODING=b;TYPE=png:data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAA

SUCCESSFUL: PHOTO;ENCODING=B;VALUE=BINARY:/9j/4AAQSkZJRgABAQECWAJYAAD/2wBDAAgGBgcGBQ

I'm using this script to do the test:

import vobject
file = "./whatever.vcf"
with open(file) as f:
    vcard = vobject.readOne(f)
with open(file) as f:
    raw = f.read()
print(vcard.serialize())
print(raw)

In the cases where the parsing fails this is the output:

Traceback (most recent call last):
  File "/usr/lib/python3.8/encodings/base64_codec.py", line 19, in base64_decode
    return (base64.decodebytes(input), len(input))
  File "/usr/lib/python3.8/base64.py", line 546, in decodebytes
    return binascii.a2b_base64(s)
binascii.Error: Incorrect padding

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "./vcardtest.py", line 6, in <module>
    vcard = vobject.readOne(f)
  File "/usr/lib/python3/dist-packages/vobject/base.py", line 1155, in readOne
    return next(readComponents(stream, validate, transform, ignoreUnreadable,
  File "/usr/lib/python3/dist-packages/vobject/base.py", line 1120, in readComponents
    component.setBehaviorFromVersionLine(versionLine)
  File "/usr/lib/python3/dist-packages/vobject/base.py", line 663, in setBehaviorFromVersionLine
    self.setBehavior(v)
  File "/usr/lib/python3/dist-packages/vobject/base.py", line 170, in setBehavior
    obj.autoBehavior(True)
  File "/usr/lib/python3/dist-packages/vobject/base.py", line 156, in autoBehavior
    self.behavior.decode(self)
  File "/usr/lib/python3/dist-packages/vobject/vcard.py", line 143, in decode
    line.value = codecs.decode(line.value.encode("utf-8"), "base64")
binascii.Error: decoding with 'base64' codec failed (Error: Incorrect padding)

If this is a vobject issue, Is there any way to work around it?