BSD 3 development

[unix-history] / usr / src / cmd / login.c

/*
* login [ name ]
*/

#include <sys/types.h>
#include <sgtty.h>
#include <utmp.h>
#include <signal.h>
#include <pwd.h>
#include <stdio.h>
#include <sys/stat.h>
#include <lastlog.h>
#define SCPYN(a, b)     strncpy(a, b, sizeof(a))

char    maildir[30] =   "/usr/spool/mail/";
char    lastlog[] =     "/usr/adm/lastlog";
struct  passwd nouser = {"", "nope"};
struct  sgttyb ttyb;
struct  utmp utmp;
char    minusnam[16] = "-";
char    homedir[64] = "HOME=";
char    shell[64] = "SHELL=";
char    term[64] = "TERM=";
char    *envinit[] = {homedir, shell, "PATH=:/usr/ucb:/bin:/usr/bin", term, 0};
struct  passwd *pwd;

struct  passwd *getpwnam();
char    *strcat();
int     setpwent();
char    *ttyname();
char    *crypt();
char    *getpass();
char    *rindex();
char    *stypeof();
extern  char **environ;

main(argc, argv)
char **argv;
{
       register char *namep;
       int t, f, c;
       char *ttyn;

       alarm(60);
       signal(SIGQUIT, SIG_IGN);
       signal(SIGINT, SIG_IGN);
       nice(-100);
       nice(20);
       nice(0);
       gtty(0, &ttyb);
       ttyb.sg_erase = '#';
       ttyb.sg_kill = '@';
       stty(0, &ttyb);
       for (t=3; t<20; t++)
               close(t);
       ttyn = ttyname(0);
       if (ttyn==0)
               ttyn = "/dev/tty??";

   loop:
       SCPYN(utmp.ut_name, "");
       if (argc>1) {
               SCPYN(utmp.ut_name, argv[1]);
               argc = 0;
       }
       while (utmp.ut_name[0] == '\0') {
               namep = utmp.ut_name;
               printf("login: ");
               while ((c = getchar()) != '\n') {
                       if(c == ' ')
                               c = '_';
                       if (c == EOF)
                               exit(0);
                       if (namep < utmp.ut_name+8)
                               *namep++ = c;
               }
       }
       setpwent();
       if ((pwd = getpwnam(utmp.ut_name)) == NULL)
               pwd = &nouser;
       endpwent();
       if (*pwd->pw_passwd != '\0') {
               namep = crypt(getpass("Password:"),pwd->pw_passwd);
               if (strcmp(namep, pwd->pw_passwd)) {
bad:
                       printf("Login incorrect\n");
                       if (ttyn[8] == 'd') {
                               FILE *console = fopen("/dev/console", "w");
                               if (console != NULL) {
                                       fprintf(console, "\r\nBADDIALUP %s %s\r\n", ttyn+5, utmp.ut_name);
                                       fclose(console);
                               }
                       }
                       goto loop;
               }
       }
/*
       if (pwd->pw_uid == 0 && ttyn[5] != 'c')
               goto bad;
*/
       if (ttyn[8] == 'd') {
               FILE *console = fopen("/dev/console", "w");
               if (console != NULL) {
                       fprintf(console, "\r\nDIALUP %s %s\r\n", ttyn+5, pwd->pw_name);
                       fclose(console);
               }
       }
       if((f = open(lastlog, 2)) >= 0) {
               struct lastlog ll;

               lseek(f, pwd->pw_uid * sizeof (struct lastlog), 0);
               if (read(f, (char *) &ll, sizeof ll) == sizeof ll && ll.ll_time != 0) {
                       register char *ep = (char *) ctime(&ll.ll_time);
                       printf("Last login: ");
                       ep[24 - 5] = 0;
                       printf("%s on %.8s\n", ep, ll.ll_line);
               }
               lseek(f, pwd->pw_uid * sizeof (struct lastlog), 0);
               time(&ll.ll_time);
               strcpyn(ll.ll_line, ttyn+5, 8);
               write(f, (char *) &ll, sizeof ll);
       }
       if(chdir(pwd->pw_dir) < 0) {
               printf("No directory\n");
               goto loop;
       }
       time(&utmp.ut_time);
       t = ttyslot();
       if (t>0 && (f = open("/etc/utmp", 1)) >= 0) {
               lseek(f, (long)(t*sizeof(utmp)), 0);
               SCPYN(utmp.ut_line, rindex(ttyn, '/')+1);
               write(f, (char *)&utmp, sizeof(utmp));
               close(f);
       }
       if (t>0 && (f = open("/usr/adm/wtmp", 1)) >= 0) {
               lseek(f, 0L, 2);
               write(f, (char *)&utmp, sizeof(utmp));
               close(f);
       }
       chown(ttyn, pwd->pw_uid, pwd->pw_gid);
       setgid(pwd->pw_gid);
       setuid(pwd->pw_uid);
       if (*pwd->pw_shell == '\0')
               pwd->pw_shell = "/bin/sh";
       environ = envinit;
       strncat(homedir, pwd->pw_dir, sizeof(homedir)-6);
       strncat(shell, pwd->pw_shell, sizeof(shell)-7);
       strncat(term, stypeof(ttyn), sizeof(term)-6);
       if ((namep = rindex(pwd->pw_shell, '/')) == NULL)
               namep = pwd->pw_shell;
       else
               namep++;
       strcat(minusnam, namep);
       alarm(0);
       umask(022);
       showmotd();
       strcat(maildir, pwd->pw_name);
       if(access(maildir,4)==0) {
               struct stat statb;
               stat(maildir, &statb);
               if (statb.st_size)
                       printf("You have mail.\n");
       }
       signal(SIGQUIT, SIG_DFL);
       signal(SIGINT, SIG_DFL);
       execlp(pwd->pw_shell, minusnam, 0);
       printf("No shell\n");
       exit(0);
}

int     stopmotd;
catch()
{
       signal(SIGINT, SIG_IGN);
       stopmotd++;
}

showmotd()
{
       FILE *mf;
       register c;

       signal(SIGINT, catch);
       if((mf = fopen("/etc/motd","r")) != NULL) {
               while((c = getc(mf)) != EOF && stopmotd == 0)
                       putchar(c);
               fclose(mf);
       }
       signal(SIGINT, SIG_IGN);
}

#define UNKNOWN "su"

char *
stypeof(ttyid)
char    *ttyid;
{
       static char     typebuf[16];
       char            buf[50];
       register FILE   *f;
       register char   *p, *t, *q;

       if (ttyid == NULL)
               return (UNKNOWN);
       f = fopen("/etc/ttytype", "r");
       if (f == NULL)
               return (UNKNOWN);
       /* split off end of name */
       for (p = q = ttyid; *p != 0; p++)
               if (*p == '/')
                       q = p + 1;

       /* scan the file */
       while (fgets(buf, sizeof buf, f) != NULL)
       {
               for (t=buf; *t!=' '; t++)
                       ;
               *t++ = 0;
               for (p=t; *p>' '; p++)
                       ;
               *p = 0;
               if (strcmp(q,t)==0) {
                       strcpy(typebuf, buf);
                       fclose(f);
                       return (typebuf);
               }
       }
       fclose (f);
       return (UNKNOWN);
}