Re: parsing quoted-string HTTP header fields

Here are two patches the first implements the (1) and the second the (3).
The second patch does not look slower, but maybe we do not want to be
strict for many reasons. One reason is that this function used to
"Configurable SSL error details messages" patch, to parse the "descr:"
and "detail:" fields :-)
The other reason is that it is usual to find web clients or servers
which uses a simple "\n" instead of the "\r\n"...

On 05/25/2011 02:51 PM, Amos Jeffries wrote:
> On 25/05/11 22:44, Tsantilas Christos wrote:
>> The quoted string fields parsing done in squid3 using the
>> httpHeaderParseQuotedString function (HttpHeaderTools.cc file)
>>
>> I found that we do not support multiline quoted string fields, but
>> according the rfc2616 multiline quoted string fields should supported:
>>
>> quoted-string = ( <"> *(qdtext | quoted-pair ) <"> )
>> qdtext = <any TEXT except <">>
>> TEXT = <any OCTET except CTLs,
>> but including LWS>
>> LWS = [CRLF] 1*( SP | HT
>>
>>
>>
>> I am planning to fix the httpHeaderParseQuotedString function, using one
>> of the following rules:
>>
>> 1) Just ignore any "\r" or "\n" character. This is the fastest and
>> simpler approach
>> 3) Require "\r\n " or "\r\n\t" as line separator and just remove the
>> "\r\n"
>> 3) Require "\r\n " or "\r\n\t" as line separator and replace it with a
>> space
>> 4) Also support "\n\t" or "\n\n\t" as line separators.
>
> (4) case #2 "\n\n\t" is also non-compliant.
>
>>
>> Any comments or suggestions?
>
> RFC states "A recipient MAY replace any linear white space with a single
> SP".
>
> So (1) and the second (3) {replace with 0x20} are the valid options.
>
> It may be worth having two quoted-string parsers. One for each option.
> The preference being (1) for its higher performance.
>
> Amos
Received on Wed May 25 2011 - 17:07:21 MDT