Re: SSL_peek() removes the session ticket from the underlying BIO ??

[Matt Caswell]

On 02/05/2024 11:52, Rahul Shukla wrote:

Thank you for the quick reply, Matt !!

Is my understanding correct thatif the buffer is empty and SSL_peek() is 
invoked while trying to process more records, only application data gets 
placed into that buffer?



Technically, the internal buffer is reused to temporarily hold the 
non-application data.  But that is invisible to callers of 
SSL_peek()/SSL_read(). While the internal buffer is holding 
non-application data any calls to SSL_peek()/SSL_read() will return no 
data (if a non-blocking socket is in use), or will block until app data 
is available (if a blocking socket is in use).


Matt




--Rahul


On Thu, May 2, 2024 at 12:33 PM Matt Caswell > wrote:




On 02/05/2024 06:19, Rahul Shukla wrote:
 > Hi All,
 > As per the OpenSSL doc :
 > /
 > /
 > /"SSL_peek_ex() and SSL_peek() are identical to SSL_read_ex() and
 > SSL_read() respectively except no bytes are actually removed from
the
 > underlying BIO during the read, so that a subsequent call to
 > SSL_read_ex() or SSL_read() will yield at least the same bytes."/
 >
 > *I have a quick question here, Does SSL_peek() remove the session
ticket
 > (Non application data) from the underlying BIO or will it remain
there
 > just like application data until unless SSL_read() is called to
read the
 > session ticket. *


It depends.

OpenSSL has an internal buffer of application data that has already
been
processed and is available for immediate read. If that buffer has data
in it then a call to SSL_peek() (or in fact SSL_read()) will return
that
data and will not attempt to process any further incoming records.

If the buffer is empty then it will attempt to process further records
in order to put more data into that buffer. In doing that if it
encounters any non-application data records (such as a session ticket)
then it will process those records in the same way as SSL_read() would
have done.

Matt

Re: SSL_peek() removes the session ticket from the underlying BIO ??

[Rahul Shukla]

Thank you for the quick reply, Matt !!

Is my understanding correct that if the buffer is empty and SSL_peek() is
invoked while trying to process more records, only application data gets
placed into that buffer?

--Rahul


On Thu, May 2, 2024 at 12:33 PM Matt Caswell  wrote:

>
>
> On 02/05/2024 06:19, Rahul Shukla wrote:
> > Hi All,
> > As per the OpenSSL doc :
> > /
> > /
> > /"SSL_peek_ex() and SSL_peek() are identical to SSL_read_ex() and
> > SSL_read() respectively except no bytes are actually removed from the
> > underlying BIO during the read, so that a subsequent call to
> > SSL_read_ex() or SSL_read() will yield at least the same bytes."/
> >
> > *I have a quick question here, Does SSL_peek() remove the session ticket
> > (Non application data) from the underlying BIO or will it remain there
> > just like application data until unless SSL_read() is called to read the
> > session ticket. *
>
>
> It depends.
>
> OpenSSL has an internal buffer of application data that has already been
> processed and is available for immediate read. If that buffer has data
> in it then a call to SSL_peek() (or in fact SSL_read()) will return that
> data and will not attempt to process any further incoming records.
>
> If the buffer is empty then it will attempt to process further records
> in order to put more data into that buffer. In doing that if it
> encounters any non-application data records (such as a session ticket)
> then it will process those records in the same way as SSL_read() would
> have done.
>
> Matt
>

Re: SSL_peek() removes the session ticket from the underlying BIO ??

[Matt Caswell]

On 02/05/2024 06:19, Rahul Shukla wrote:

Hi All,
As per the OpenSSL doc :
/
/
/"SSL_peek_ex() and SSL_peek() are identical to SSL_read_ex() and 
SSL_read() respectively except no bytes are actually removed from the 
underlying BIO during the read, so that a subsequent call to 
SSL_read_ex() or SSL_read() will yield at least the same bytes."/


*I have a quick question here, Does SSL_peek() remove the session ticket 
(Non application data) from the underlying BIO or will it remain there 
just like application data until unless SSL_read() is called to read the 
session ticket. *



It depends.

OpenSSL has an internal buffer of application data that has already been 
processed and is available for immediate read. If that buffer has data 
in it then a call to SSL_peek() (or in fact SSL_read()) will return that 
data and will not attempt to process any further incoming records.


If the buffer is empty then it will attempt to process further records 
in order to put more data into that buffer. In doing that if it 
encounters any non-application data records (such as a session ticket) 
then it will process those records in the same way as SSL_read() would 
have done.


Matt

SSL_peek() removes the session ticket from the underlying BIO ??

[Rahul Shukla]

Hi All,
As per the OpenSSL doc :

*"SSL_peek_ex() and SSL_peek() are identical to SSL_read_ex() and
SSL_read() respectively except no bytes are actually removed from the
underlying BIO during the read, so that a subsequent call to SSL_read_ex()
or SSL_read() will yield at least the same bytes."*

*I have a quick question here, Does SSL_peek() remove the session ticket
(Non application data) from the underlying BIO or will it remain there just
like application data until unless SSL_read() is called to read the session
ticket. *


--Rahul