Re: [PATCH 5/6] gatchat: support for auth NONE

[Denis Kenzior <denkenz@gmail.com>]

[-- Attachment #1: Type: text/plain, Size: 1443 bytes --]

Hi Giacinto,

On 10/02/2018 01:26 AM, Giacinto Cifelli wrote:
> Added authentication method G_AT_PPP_AUTH_METHOD_NONE and its handling.
> 
> This method is already used in the code, and

Hmm, I don't think so?

> the patch is just allowing its explicit use, on top of the implicit
> selection done when username is empty.

I do not see how this is true?  Even if username / password is empty, 
the CHAP/PAP authentication method applies.  We just hash the empty 
password for CHAP / send it plaintext for PAP.

There is of course the possibility that the PPP server can simply not 
ask us for the AUTH_PROTO option, in which case we would find that 
acceptable and the auth protocol would not be used.

> ---
>   gatchat/gatppp.c  | 3 ++-
>   gatchat/gatppp.h  | 1 +
>   gatchat/ppp_lcp.c | 3 +++
>   3 files changed, 6 insertions(+), 1 deletion(-)
> 

<snip>

> diff --git a/gatchat/ppp_lcp.c b/gatchat/ppp_lcp.c
> index df9cd0ef..258ae763 100644
> --- a/gatchat/ppp_lcp.c
> +++ b/gatchat/ppp_lcp.c
> @@ -279,6 +279,9 @@ static enum rcr_result lcp_rcr(struct pppcp_data *pppcp,
>   				*new_len = 4;
>   
>   				return RCR_NAK;
> +
> +			case G_AT_PPP_AUTH_METHOD_NONE:
> +				return RCR_ACCEPT;

Should this not be RCR_REJECT ?  Otherwise we're accepting a server 
proposed auth protocol when we're explicitly configured not to use one.

>   			}
>   			break;
>   		}
> 

Regards,
-Denis