possible idn decoding bug (at least as of 1.25)

[Jon Nelson]

I've found what I believe to be a bug in libidn (<= 1.25, didn't check
more recent versions).

The following IDNA-encoded domain, when run through idn, does not
result in an error.

xn--9k39ivpi18g4vn.cn

However, Python does complain:

python -c "'xn--9k39ivpi18g4vn.cn'.decode('idna')"

Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/usr/lib64/python2.7/encodings/idna.py", line 193, in decode
    result.append(ToUnicode(label))
  File "/usr/lib64/python2.7/encodings/idna.py", line 131, in ToUnicode
    result = label1.decode("punycode")
  File "/usr/lib64/python2.7/encodings/punycode.py", line 208, in decode
    res = punycode_decode(input, errors)
  File "/usr/lib64/python2.7/encodings/punycode.py", line 195, in
punycode_decode
    return insertion_sort(base, extended, errors)
  File "/usr/lib64/python2.7/encodings/punycode.py", line 177, in insertion_sort
    raise UnicodeError, ("Invalid character U+%x" % char)
UnicodeError: Invalid character U+160bb4


-- 
Jon Nelson