NIS -Netgroups

What NIS Does:
Nis distributes information to the machines in the department. Netgroups consist of two types
Machine groups and User groups. We use the machine groups to control ssh logins, information distribution,
and user logins.
The size of Netgroups is limited to only 1024 characters. Our netgroups are larger than this. We have script to set up netgroups located in /var/yp/bin/build_netgroups, because of this size constraint.

Netgroups - Uses:

admin - refers to the wheel group of sys admins
homers- previously used to export home directories
freebsd - free bsd machines -not up to date
insiders - groups of machines which are allowed to ssh into each other
seo200solaris - list of machines in seo 200 - for undergraduate use.
students - list of student users , who only are only allowed to log into the machines in seo200
math - list of users who are allowed to log into all machines.
sunsolaris - List of Sun Solaris Machines
xhosts - list of xhost machines
quotauser - vladimir group

Netgroups - Status and Files Referenced:

admin - not currently used - possiblity for use: these lines are newton's /etc/passwd vladimir:x:31415:31415:Vladimir V Egorin:/home/2/vladimir:/bin/bash

sysadmin:x:11:11:Sysadmin:/home/8/SA:/bin/csh

culler:x:30007:30007:Marc Culler:/home/4/culler:/bin/bash

burgiel:x:31887:31887:Heidi Burgiel:/home/4/burgiel:/bin/bash

irina:x:30119:30119:Irina Perepelitsa:/home/4/irina:/bin/bash

dye:x:30225:30225:Heather A. Dye:/home/4/dye:/bin/bash

wolfgang:x:1244:1244:Wolfgang McKeown:/home/6/wolfgang:/bin/bash

could replace with +@admin:x:::::

homers - may not be used. Exported home directories. Galileo now exports to all 3 subnets.
freebsd - no references, not up to date - may not be used
insiders - up to date - references in /etc/hosts.allow
seo200solaris - up to date, referenced in the auto_master and labauto_master files. Home directories are mounted differently by lab machines.
students - up to date -referenced in /etc/passwd as: -@students:x::::: and adduser script
math - up to date - referenced in /etc/passwd as:+@math:x::::: and adduser script
sunsolaris - up to date - referenced in /etc/dfs/dfstab on newton and export list of /opt , /usr/local
xhosts - obsolete - list of xhost computers which have been discarded.
quotauser - obsolete

Netgroups - Adding a New Machine
- this is used in the solaris jumpstart, each time we add a new sun machine.

Reference README file in /var/yp
edit file with list of machines/users
cd /var/yp ; run /var/yp/bin/build_netgroups; in /var/yp make;

Netgroups - Adding a New Netgroup

create file listing machines/users in /var/yp/NETGROUPS
name of file is the name of the netgroup
add neccessary references to files using cfengine etc
buildnetgroups again
DOCUMENT: Purpose of NETGROUP and all files referencing this NETGROUP

NETgroups referenced in files:
/etc/dfs/dfstab on newton: in the export list for /opt and /usr/local.

It could be used. For example, instead of having this in newton's

/etc/passwd:

vladimir:x:31415:31415:Vladimir V Egorin:/home/2/vladimir:/bin/bash
sysadmin:x:11:11:Sysadmin:/home/8/SA:/bin/csh
culler:x:30007:30007:Marc Culler:/home/4/culler:/bin/bash
burgiel:x:31887:31887:Heidi Burgiel:/home/4/burgiel:/bin/bash
irina:x:30119:30119:Irina Perepelitsa:/home/4/irina:/bin/bash
dye:x:30225:30225:Heather A. Dye:/home/4/dye:/bin/bash
wolfgang:x:1244:1244:Wolfgang McKeown:/home/6/wolfgang:/bin/bash

you could use:

+@admin:x:::::

and put us in the admin netgroup.

/etc/hosts.allow
/etc/passwd
right. In turn, labauto_master exists so that automounter
consulted labauto.direct

Why Net groups:

netgroups are limited to 1024 characters, insufficient for need.
use the make netgroups stuff:

netgroups -> gen file netgroup

#include <ctype.h>
#include <strings.h>
#include <pwd.h>
#include <stdio.h>
#include <sys/types.h>
#include <unistd.h>
#include <dirent.h>
#define NGRPDIR "/var/yp/NETGROUPS"
#define ngrptmp "/var/yp/netgroup.tmp"
#define MAXL 1019
#define DEBUG 0
#define DBG if(DEBUG) fprintf

FILE *nf; /* ngrptmp */

void make_netgroup(struct dirent *);
char *find_word(char s[255]);

int main(void) {
        DIR *dirp;
        struct dirent *dp;
        char *t;
        char bad = 0;

        if( (nf = fopen(ngrptmp,"w")) == NULL) {
                perror(ngrptmp);
                exit(2);
        }
        if( (dirp=opendir(NGRPDIR)) == NULL) {
                perror(NGRPDIR);
                exit(2);
        }
        if(chdir(NGRPDIR)<0) {
                perror(NGRPDIR);
                exit(2);
        }
        while( (dp = readdir(dirp)) != NULL) {
                bad = 0;
                if( (!strcmp(dp->d_name,".")) || (!strcmp(dp->d_name,"..")) )
                        continue;
                for(t=dp->d_name; *t; t++) {
                        if( (*t == '~') || (*t == '.') ) {
                                printf("\007---->BAD filename: %s. Skipping.\n", dp->d_name);
                                bad = 1;
                                break;

}

                if (bad) continue;

                DBG(stderr,"dir entry: %s\n", dp->d_name);
        /*      if(isdigit(dp->d_name[strlen(dp->d_name) - 1])) {
                        printf("\007---->BAD filename: %s. Skipping.\n", dp->d_name);
                        continue;
                } */
                printf("Making %s\n", dp->d_name);
                make_netgroup(dp);
        }
        (void) closedir(dirp);
        fclose(nf);
        if(rename(ngrptmp,"/var/yp/netgroup") < 0) {
                perror("Could not rename to /var/yp/netgroup");
                exit(2);
        }
        printf("Now you can type /usr/ccs/bin/make.\n");
        exit(0);
void make_netgroup(struct dirent *dp) {
        char o[2048];
        char i[255];
        int j;
        int count;
        static char *wordp;
        struct hostent *h;
        int table_type; /* 0 = hosts; 1 = users */
        FILE *fp;
        char temp[255];
        DBG(stderr,"Entered make_netgroup.\n");
        *o = 0;
        if( (fp = fopen(dp->d_name, "r")) == NULL) {
                perror(dp->d_name);
                return;
        }
        DBG(stderr,"Opened: %s\n", dp->d_name);
        count = 0;
        if(fgets(i,255,fp) == NULL) return;
        wordp = find_word(i);
        if(!strcmp(wordp,"USERS"))
                table_type = 1;

     else if(!strcmp(wordp, "HOSTS"))
                table_type = 0;
        else {
                fprintf(stderr,"%s: unknows table type. Skipped.\n", dp->d_name);
                return;
        }
        DBG(stderr,"table type: %d\n", table_type);

        if(fgets(i,255,fp) == NULL) return;
        wordp = find_word(i);
        if(strlen(dp->d_name) + 3 + strlen(wordp) + 6 > MAXL-1) {
                fprintf(stderr,"%s: host name too long.\n", wordp);
                return;
        }
        if(table_type)
                sprintf(o,"%s%d (-,%s,) ", dp->d_name,count, wordp);
        else
                sprintf(o,"%s%d (%s,-,) ", dp->d_name,count, wordp);
        while ( fgets(i,255,fp) != NULL) {
                wordp = find_word(i);
                if(!wordp) continue;
                if(strlen(wordp) + strlen(o) + 6 > MAXL-1) {
:
                       fprintf(nf,"%s\n",o);
                        if(strlen(dp->d_name) + 2 + strlen(wordp) + 6 > MAXL-1) {
                                fprintf(stderr,"%s: name too long.\n", wordp);
                                return;
                        }
                        count++;
                        if(table_type)
                                sprintf(o,"%s%d (-,%s,) ", dp->d_name,count, wordp);
                        else
                                sprintf(o,"%s%d (%s,-,) ", dp->d_name,count, wordp);
                        continue;
                } else {
                        if(table_type)
                                sprintf(temp,"(-,%s,) ", wordp);
                        else
                                sprintf(temp,"(%s,-,) ", wordp);
                        strcat(o,temp);
                }
        }
        fprintf(nf,"%s\n",o);

      fprintf(nf,"%s ",dp->d_name);
        for(j=0;j<=count;j++) {
                fprintf(nf,"%s%d ", dp->d_name,j);
        }
        fprintf(nf,"\n");
        return;
}

char *find_word(char s[255]) {
        char *p;
        char *e;
        static char wordp[255];
        DBG(stderr,"Entered find_word.\n");
        for(p=s;!( isalpha(*p)||isdigit(*p) ); p++);
        for(e=p; isalpha(*e) || isdigit(*e) || (*e == '-') || (*e == '.'); e++);        *e = 0;
        if(p-e > 254) return 0;
        snprintf(wordp,255,p);
        DBG(stderr,"putting word: %s\n", wordp);
        return wordp;
}