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- Slackware (https://www.linuxquestions.org/questions/slackware-14/)

- - no crypt (https://www.linuxquestions.org/questions/slackware-14/no-crypt-549127/)

dear members,

iam missing the crypt-command in my slackware 10.2.

iam a newbee @linux and want to add a sytem-user using a servlet.
i need one command-line to add a user and set the encryptet pw.

can anyone help me ?

greez

you want to add a user in one command ? hehe try man useradd.

it will probably be something like

useradd -d /home/username -s /bin/bash -p password username

>> useradd -d /home/username -s /bin/bash -p password username

ofcourse...but in this case i must give the password crypted.

so i need a script or a single commandline witch crypt the pw and give it to the
useradd command.

I searched for that some days ago, but although I have a strong hint I could not get it working - the computed output and the entry in /etc/shadow (generated from "passwd") still differ. openssl might be able to do this: http://www.linuxjournal.com/node/8958/print

Give it some salt and the meal is ready :)
http://www.madboa.com/geek/openssl/#passwd-md5

Perhaps you mean something like this?

This program, cvspas, is used to generate the password entry for CVS; it prompts for the password and prints the login name of the person running the program along with the encrypted password.

The output is, for example,

Code:

# cvspas

Password to encrypt: type_the_password

userid:KeGoQCkfp7XYw

Compile it with

Code:

cc -O3 -s -o cvspas cvspas.c -lcrypt

Here's the source.

Code:

#include <stdio.h>

#include <stdlib.h>

#include <pwd.h>

#include <time.h>

#define _XOPEN_SOURCE

#include <unistd.h>



extern  char    *crypt  (const char *, const char *);



int    main    (int argc, char *argv [])

{

        char    salt [3];

        char    *passwd, *encryptedpw;

        char    *user;

        int    i;



        /*      seed the random number generator        */

        srand ((int) time ((unsigned int) NULL));

        /*

        *      we need two random numbers in the range

        *      >= 65 <= 90 or >= 97 <= 122 (that's A - Z

        *      or a - z inclusive) for the salt characters

        */

        while ((i = rand()) < 65 ||

                i > 90 && i < 97 ||

                i > 122)

                ;

        salt [0] = i;

        while ((i = rand()) < 65 ||

                i > 90 && i < 97 ||

                i > 122)

                ;

        salt [1] = i;

        salt [2] = '\0';

        /*      find out who we are                    */

        if ((user = getenv ("USER")) == (char *) NULL) {

                (void) fprintf (stderr,

                    "%s:\tunable to determine user id\n",

                    argv [0]);

                exit (EXIT_FAILURE);

        }

        /*      ask for the password                    */

        passwd = getpass ("Password to encrypt: ");

        /*      crypt() only looks at the first two characters of salt  */

        encryptedpw = crypt (passwd, salt);

        (void) fprintf (stdout, "%s:%s\n", user, encryptedpw);

        exit (EXIT_SUCCESS);

}

Now, this is just a demonstration program -- the use of the rand() function to generate the salt characters is not the most efficient way to that and, consequently, the program takes a few seconds before the password prompt appears. But, it does produce a usable encrypted password so there you are.

See the manual pages for the functions the program calls if you want more information.

thanks for the script!

i tryed the openssl and it seams to work fine.
now my next question:

how can i combinate the openssl command with the useradd command in ONE line to generate a new user with encrypted password ?

many thanks...

It's not exactly a one-liner, although you can of course append the lines with ";". And it's not the best method I guess.
I export first some variables, a better choice I guess would to put the lines in a bash script and use parameters $1 $2 and $3 instead of the static export lines.

Code:

export SET_USER=username

export SET_SALT=3gZekj8m # should be random of course

export SET_PASSWD=mypassword

export ENC_PASSWD=$(openssl passwd -1 -salt $SET_SALT $SET_PASSWD)

useradd -g users -G video,cdrom,floppy -m -p "$ENC_PASSWD" -s /bin/bash $SET_USER



# clean up, not necessary if called from script

unset SET_USER SET_SALT SET_PASSWD ENC_PASSWD

EDIT: I assumed you might want to use it in a bash script to automate the process of creating a user. If you don't need this you could simplify my script and write all commands in one line:

Code:

export ENC_PASSWD=$(openssl passwd -1 -salt 3gZekj8m mypassword) ; useradd -g users -G video,cdrom,floppy -m -p "$ENC_PASSWD" -s /bin/bash username ; unset ENC_PASSWD

EDIT 2: Even shorter works too:

Code:

useradd -g users -G video,cdrom,floppy -m -p "$(openssl passwd -1 -salt 3gZekj8m mypassword)" -s /bin/bash username