[rabbitmq-discuss] Authenticate client using certificate only

[Gordon Sim]

On 08/19/2010 09:51 AM, jiri at krutil.com wrote:
>   %% AMQPLAIN, as used by Qpid Python test suite. The 0-8 spec actually
>   %% defines this as PLAIN, but in 0-9 that definition is gone, instead
>   %% referring generically to "SASL security mechanism", i.e. the above.
> -check_login(<<"AMQPLAIN">>, Response) ->
> -    LoginTable = rabbit_binary_parser:parse_table(Response),
> -    case {lists:keysearch(<<"LOGIN">>, 1, LoginTable),
> -          lists:keysearch(<<"PASSWORD">>, 1, LoginTable)} of
> -        {{value, {_, longstr, User}},
> -         {value, {_, longstr, Pass}}} ->
> -            user_pass_login(User, Pass);
> -        _ ->
> -            %% Is this an information leak?
> -            rabbit_misc:protocol_error(
> -              access_refused,
> -              "AMQPPLAIN auth info ~w is missing LOGIN or PASSWORD field",
> -              [LoginTable])
> +check_login(<<"AMQPLAIN">>, Response, Sock) ->
> +    case is_record(Sock, ssl_socket) andalso Sock#ssl_socket.cn /= none of
> +        true ->
> +            certificate_login(Sock);
> +        false ->
> +            LoginTable = rabbit_binary_parser:parse_table(Response),
> +            case {lists:keysearch(<<"LOGIN">>, 1, LoginTable),
> +                  lists:keysearch(<<"PASSWORD">>, 1, LoginTable)} of
> +                {{value, {_, longstr, User}},
> +                 {value, {_, longstr, Pass}}} ->
> +                    user_pass_login(User, Pass);
> +                _ ->
> +                    %% Is this an information leak?
> +                    rabbit_misc:protocol_error(
> +                      access_refused,
> +                      "AMQPPLAIN auth info ~w is missing LOGIN or PASSWORD field",
> +                      [LoginTable])
> +            end
>       end;

The SASL EXTERNAL mechanism is intended for just such use cases (i.e. 
where the underlying transport authenticates itself and no further 
exchange is required). So a nice way (though perhaps a slightly more 
involved patch) might be to offer that mechanism on SSL connections. 
Just a suggestion however.