Query regarding SSL_ERROR_SSL during SSL handshake

[Mahendra SP]

Hi All,

We are using Openssl version 1.0.2h. When we call SSL_do_handshake,
sometimes we notice that handshake fails with error SSL_ERROR_SSL.
As per the documentation for this error, it is non recoverable and fatal
error.  Documentation also mentions to check the error queue for further
details. Does it mean, calling SSL_get_error after SSL_ERROR_SSL will give
exact reason for this failure?

Could you please let me know ways to identify the cause of this error?

Thanks
Mahendra

Re: Query regarding SSL_ERROR_SSL during SSL handshake

[Matt Caswell]

On 19/02/2020 05:16, Mahendra SP wrote:
> Hi All,
> 
> We are using Openssl version 1.0.2h. When we call SSL_do_handshake,
> sometimes we notice that handshake fails with error SSL_ERROR_SSL. 
> As per the documentation for this error, it is non recoverable and fatal
> error.  Documentation also mentions to check the error queue for further
> details. Does it mean, calling SSL_get_error after SSL_ERROR_SSL will
> give exact reason for this failure? 

OpenSSL has its own error stack. SSL_ERROR_SSL means that you should
look at that error stack for further details about what caused the
problem. For example you can use ERR_print_errors_fp() to print all the
error descriptions to stdout/stderr:

https://www.openssl.org/docs/man1.1.1/man3/ERR_print_errors_fp.html

You can get more fine grained control of the error stack using the
various ERR_* functions available. See:

https://www.openssl.org/docs/man1.1.1/man3/

Matt

Re: Query regarding SSL_ERROR_SSL during SSL handshake

[Mahendra SP]

Hi Matt,

Thank you for the inputs.
I have one more query. Is it appropriate to check for the errno in this
case and take action based on the errno values ?

Thanks
Mahendra

On Wed, Feb 19, 2020 at 3:09 PM Matt Caswell  wrote:

>
>
> On 19/02/2020 05:16, Mahendra SP wrote:
> > Hi All,
> >
> > We are using Openssl version 1.0.2h. When we call SSL_do_handshake,
> > sometimes we notice that handshake fails with error SSL_ERROR_SSL.
> > As per the documentation for this error, it is non recoverable and fatal
> > error.  Documentation also mentions to check the error queue for further
> > details. Does it mean, calling SSL_get_error after SSL_ERROR_SSL will
> > give exact reason for this failure?
>
> OpenSSL has its own error stack. SSL_ERROR_SSL means that you should
> look at that error stack for further details about what caused the
> problem. For example you can use ERR_print_errors_fp() to print all the
> error descriptions to stdout/stderr:
>
> https://www.openssl.org/docs/man1.1.1/man3/ERR_print_errors_fp.html
>
> You can get more fine grained control of the error stack using the
> various ERR_* functions available. See:
>
> https://www.openssl.org/docs/man1.1.1/man3/
>
> Matt
>

Re: Query regarding SSL_ERROR_SSL during SSL handshake

[Matt Caswell]

On 24/02/2020 03:49, Mahendra SP wrote:
> Hi Matt,
> 
> Thank you for the inputs. 
> I have one more query. Is it appropriate to check for the errno in this
> case and take action based on the errno values ?

No, errno should not be checked unless SSL_get_error returns
SSL_ERROR_SYSCALL.

Matt


> 
> Thanks
> Mahendra
> 
> On Wed, Feb 19, 2020 at 3:09 PM Matt Caswell  > wrote:
> 
> 
> 
> On 19/02/2020 05:16, Mahendra SP wrote:
> > Hi All,
> >
> > We are using Openssl version 1.0.2h. When we call SSL_do_handshake,
> > sometimes we notice that handshake fails with error SSL_ERROR_SSL. 
> > As per the documentation for this error, it is non recoverable and
> fatal
> > error.  Documentation also mentions to check the error queue for
> further
> > details. Does it mean, calling SSL_get_error after SSL_ERROR_SSL will
> > give exact reason for this failure?
> 
> OpenSSL has its own error stack. SSL_ERROR_SSL means that you should
> look at that error stack for further details about what caused the
> problem. For example you can use ERR_print_errors_fp() to print all the
> error descriptions to stdout/stderr:
> 
> https://www.openssl.org/docs/man1.1.1/man3/ERR_print_errors_fp.html
> 
> You can get more fine grained control of the error stack using the
> various ERR_* functions available. See:
> 
> https://www.openssl.org/docs/man1.1.1/man3/
> 
> Matt
>