"Marc Mamin" <m.mamin@intershop.de> writes:
> I didn't check if all characters are valid UTF8...
They aren't ...
> select f_utf8_test('(Mozilla/4.0 (compatible; MSIE 6.0; Wind
> \xE0\xF0\xF1\xF2\xE2\xE5\xED\xED\xFB\xE9 \xE2\xFB\xF1\xF8\9
> \xE3\xEE\xF1\xF3\xE4
> xE4\xE6 \xCD\xC1 \xD0\xC1")');
In 8.3 that will throw an error:
utf8=# select f_utf8_test('(Mozilla/4.0 (compatible; MSIE 6.0; Wind
utf8'# \xE0\xF0\xF1\xF2\xE2\xE5\xED\xED\xFB\xE9 \xE2\xFB\xF1\xF8\9
utf8'# \xE3\xEE\xF1\xF3\xE4
utf8'# xE4\xE6 \xCD\xC1 \xD0\xC1")');
WARNING: nonstandard use of escape in a string literal
LINE 1: select f_utf8_test('(Mozilla/4.0 (compatible; MSIE 6.0; Wind
^
HINT: Use the escape string syntax for escapes, e.g., E'\r\n'.
ERROR: invalid byte sequence for encoding "UTF8": 0xe0f0f1
HINT: This error can also happen if the byte sequence does not match the encoding expected by the server, which is
controlledby "client_encoding".
utf8=#
However, since this behavior isn't backwards-compatible, there's not
much appetite for back-patching it.
I don't think this is a security issue --- if you don't quote
backslashes in untrusted input you'll have problems far worse
than this one.
regards, tom lane