# Linux authentification check? **URL:** \ **Category:** ruby-talk\ **Created:** [7 November 2006 15:48 UTC](https://rubytalk.org/t/linux-authentification-check/32721 "2006-11-07T15:48:27Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![RHaus](https://avatars.discourse-cdn.com/v4/letter/r/e68b1a/32.png) [@RHaus](https://rubytalk.org/u/RHaus)\ **Post date:** [7 November 2006 15:48 UTC](https://rubytalk.org/t/linux-authentification-check/32721/1 "2006-11-07T15:48:27Z")
Is there a library or some other way to simply check whether a user/password combination is valid for the Linux machine I am running on? No need to actually switch the current user, change the effective group or user id etc. All I want is to make sure that the username exists and that the password is valid for that user. (I want to allow only those users to use a certain service running within a restricted server that have a userid defined on that machine) > **···** > > -- > Posted via [http://www.ruby-forum.com/](http://www.ruby-forum.com/). ---
**Author:** ![Jon\_Lim](https://avatars.discourse-cdn.com/v4/letter/j/bbce88/32.png) [@Jon\_Lim](https://rubytalk.org/u/Jon_Lim)\ **Post date:** [7 November 2006 15:54 UTC](https://rubytalk.org/t/linux-authentification-check/32721/2 "2006-11-07T15:54:24Z")
ruby-pam might be what you're looking for. > **···** > > On 07/11/06, Roman Hausner \ wrote: > > > Is there a library or some other way to simply check whether a > > user/password combination is valid for the Linux machine I am > > running on? No need to actually switch the current user, change > > the effective group or user id etc. All I want is to make sure that > > the username exists and that the password is valid for that user. > > (I want to allow only those users to use a certain service running > > within a restricted server that have a userid defined on that machine) > > > > -- > > Posted via [http://www.ruby-forum.com/\](http://www.ruby-forum.com/%5C). > > -- > > > **[snowblink](https://snowblink.co.uk/)** > > > > snowblink.co.uk : Homepage ---
**Author:** ![RHaus](https://avatars.discourse-cdn.com/v4/letter/r/e68b1a/32.png) [@RHaus](https://rubytalk.org/u/RHaus)\ **Post date:** [7 November 2006 16:55 UTC](https://rubytalk.org/t/linux-authentification-check/32721/3 "2006-11-07T16:55:12Z")
Jon Lim wrote: > ruby-pam might be what you're looking for. It seems this needs the system PAM libraries to be installed. I am not really intending to switch the authentification methods of the linux box or anything, I just want ruby to use the existing authentification method to check for a valid username/password. Maybe I am missing something, but I was expecting something like boolean = validate(username,password) and be done with it 🙂 > **···** > > -- > Posted via [http://www.ruby-forum.com/\](http://www.ruby-forum.com/%5C). ---
**Author:** ![Wilson\_Bilkovich](https://yyz1.discourse-cdn.com/flex029/user_avatar/rubytalk.org/wilson_bilkovich/32/8247_2.png) [@Wilson\_Bilkovich](https://rubytalk.org/u/Wilson_Bilkovich)\ **Post date:** [7 November 2006 17:49 UTC](https://rubytalk.org/t/linux-authentification-check/32721/4 "2006-11-07T17:49:37Z")
Are you saying that PAM isn't installed on your Linux box? If it is, you should use it. /etc/passwd is definitely not the last word in login authentication. Be careful about your assumptions, or else the guy with the smartcard won't be able to use your Ruby program. > **···** > > On 11/7/06, Roman Hausner \ wrote: > > > Jon Lim wrote: > > \> ruby-pam might be what you're looking for. > > It seems this needs the system PAM libraries to be installed. > > I am not really intending to switch the authentification methods of > > the linux box or anything, I just want ruby to use the existing > > authentification method to check for a valid username/password. > > > > Maybe I am missing something, but I was expecting something like > > boolean = validate(username,password) > > and be done with it 🙂 ---
**Author:** ![Victor\_Reyes](https://avatars.discourse-cdn.com/v4/letter/v/ed655f/32.png) [@Victor\_Reyes](https://rubytalk.org/u/Victor_Reyes)\ **Post date:** [7 November 2006 19:09 UTC](https://rubytalk.org/t/linux-authentification-check/32721/5 "2006-11-07T19:09:58Z")
Would LDAP do it? Just curious! > **···** > > On 11/7/06, Wilson Bilkovich \ wrote: > > > On 11/7/06, Roman Hausner \ wrote: > > \> Jon Lim wrote: > > \> \> ruby-pam might be what you're looking for. > > \> It seems this needs the system PAM libraries to be installed. > > \> I am not really intending to switch the authentification methods of > > \> the linux box or anything, I just want ruby to use the existing > > \> authentification method to check for a valid username/password. > > \> > > \> Maybe I am missing something, but I was expecting something like > > \> boolean = validate(username,password) > > \> and be done with it 🙂 > > \> > > > > Are you saying that PAM isn't installed on your Linux box? > > If it is, you should use it. /etc/passwd is definitely not the last > > word in login authentication. Be careful about your assumptions, or > > else the guy with the smartcard won't be able to use your Ruby > > program. ---
**Author:** ![RHaus](https://avatars.discourse-cdn.com/v4/letter/r/e68b1a/32.png) [@RHaus](https://rubytalk.org/u/RHaus)\ **Post date:** [7 November 2006 22:40 UTC](https://rubytalk.org/t/linux-authentification-check/32721/6 "2006-11-07T22:40:12Z")
Wilson Bilkovich wrote: > **···** > > > On 11/7/06, Roman Hausner \ wrote: > > > > > > > > > Are you saying that PAM isn't installed on your Linux box? > > If it is, you should use it. /etc/passwd is definitely not the last > > word in login authentication. Be careful about your assumptions, or > > else the guy with the smartcard won't be able to use your Ruby > > program. > > The linux machine is not under my control. I am just the one who writes > that server program. > > As it turns out, it already would be sufficient if I could do the same > that the "crypt" function achieves under perl. > Perl does have this as part of the core language -- how can I access > this function in ruby? > > -- > Posted via [http://www.ruby-forum.com/\](http://www.ruby-forum.com/%5C). ---
**Author:** ![Joel\_VanderWerf1](https://avatars.discourse-cdn.com/v4/letter/j/94ad74/32.png) [@Joel\_VanderWerf1](https://rubytalk.org/u/Joel_VanderWerf1)\ **Post date:** [7 November 2006 22:47 UTC](https://rubytalk.org/t/linux-authentification-check/32721/7 "2006-11-07T22:47:15Z")
Roman Hausner wrote: > As it turns out, it already would be sufficient if I could do the same > that the "crypt" function achieves under perl. > Perl does have this as part of the core language -- how can I access this function in ruby? $ ri String#crypt | cat ----------------------------------------------------------- String#crypt       str.crypt(other\_str) =\> new\_str > **···** > > ------------------------------------------------------------------------ >       Applies a one-way cryptographic hash to str by invoking the >       standard library function crypt. The argument is the salt string, >       which should be two characters long, each character drawn from >       [a-zA-Z0-9./]. > > -- >        vjoel : Joel VanderWerf : path berkeley edu : 510 665 3407 ---
**Author:** ![Gabriele\_Marrone](https://avatars.discourse-cdn.com/v4/letter/g/6a8cbe/32.png) [@Gabriele\_Marrone](https://rubytalk.org/u/Gabriele_Marrone)\ **Post date:** [7 November 2006 22:48 UTC](https://rubytalk.org/t/linux-authentification-check/32721/8 "2006-11-07T22:48:19Z")
Ruby does too, as a String method: ----------------------------------------------------------- String#crypt       str.crypt(other\_str) =\> new\_str > **···** > > Il giorno 07/nov/06, alle ore 23:40, Roman Hausner ha scritto: > > > As it turns out, it already would be sufficient if I could do the same > > that the "crypt" function achieves under perl. > > Perl does have this as part of the core language -- how can I access > > this function in ruby? > > ------------------------------------------------------------------------ >       Applies a one-way cryptographic hash to str by invoking the >       standard library function crypt. The argument is the salt string, >       which should be two characters long, each character drawn from >       [a-zA-Z0-9./]. ---
**Author:** ![snacktime](https://avatars.discourse-cdn.com/v4/letter/s/7feea3/32.png) [@snacktime](https://rubytalk.org/u/snacktime)\ **Post date:** [8 November 2006 00:50 UTC](https://rubytalk.org/t/linux-authentification-check/32721/9 "2006-11-08T00:50:46Z")
> The linux machine is not under my control. I am just the one who writes > that server program. > > As it turns out, it already would be sufficient if I could do the same > that the "crypt" function achieves under perl. Only if your server runs as root though, and only if the linux server uses the password file for authentication. ---
**Author:** ![RHaus](https://avatars.discourse-cdn.com/v4/letter/r/e68b1a/32.png) [@RHaus](https://rubytalk.org/u/RHaus)\ **Post date:** [7 November 2006 23:09 UTC](https://rubytalk.org/t/linux-authentification-check/32721/10 "2006-11-07T23:09:00Z")
Gabriele Marrone wrote: > **···** > > > Il giorno 07/nov/06, alle ore 23:40, Roman Hausner ha scritto: > > > > > As it turns out, it already would be sufficient if I could do the same > > > that the "crypt" function achieves under perl. > > > Perl does have this as part of the core language -- how can I access > > > this function in ruby? > > > > Ruby does too, as a String method: > > > > ----------------------------------------------------------- String#crypt > >       str.crypt(other\_str) =\> new\_str > > Thanks! > I was looking in all the wrong places -- wow that you say it, it seems > natural to have it as a String method 🙂 > > -- > Posted via [http://www.ruby-forum.com/\](http://www.ruby-forum.com/%5C).