Re: [Qemu-devel] [PATCH 1/1] io: ignore case in WebSocket HTTP header #PSBM-57554

[Denis V. Lunev]

On 02/27/2017 11:11 PM, Daniel P. Berrange wrote:
> On Mon, Jan 30, 2017 at 04:19:56PM +0300, Denis V. Lunev wrote:
>> From: Anton Nefedov <address@hidden>
>>
>> According to RFC7230 Section 3.2, header field name is case-insensitive.
>>
>> The haystack string length is limited by 4096 bytes by
>> qio_channel_websock_handshake_read().
>>
>> Further, handshake_process() dups and NULL-terminates the string
>> so it is safe to call non length-limited functions like strcasestr().
>>
>> Signed-off-by: Anton Nefedov <address@hidden>
>> Signed-off-by: Denis V. Lunev <address@hidden>
>> CC: Daniel P. Berrange <address@hidden>
>> ---
>>  io/channel-websock.c | 25 ++++++++++++++-----------
>>  1 file changed, 14 insertions(+), 11 deletions(-)
>>
>> diff --git a/io/channel-websock.c b/io/channel-websock.c
>> index d5a4ed3..991925a 100644
>> --- a/io/channel-websock.c
>> +++ b/io/channel-websock.c
>> @@ -108,18 +108,16 @@ enum {
>>  };
>>  
>>  static char *qio_channel_websock_handshake_entry(const char *handshake,
>> -                                                 size_t handshake_len,
>>                                                   const char *name)
>>  {
>>      char *begin, *end, *ret = NULL;
>>      char *line = g_strdup_printf("%s%s: ",
>>                                   QIO_CHANNEL_WEBSOCK_HANDSHAKE_DELIM,
>>                                   name);
>> -    begin = g_strstr_len(handshake, handshake_len, line);
>> +    begin = strcasestr(handshake, line);
> So this turns out to break Windows builds since there's no strcasestr
> on Mingw. There's no alternative that I know of in glib and I don't
> fancy implementing a custom strcasestr() function. So I'm going to
> drop this patch entirely, and copy you on an alternative fix that
> simply converts the input data to lowercase before comparison. Would
> appreciate if you can test my alternate patch with whatever client
> you had problems with.
>
> Regards,
> Daniel
Sure!