/* * 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> #define SCPYN(a, b) strncpy(a, b, sizeof(a)) char maildir[30] = "/usr/spool/mail/"; struct passwd nouser = {"", "nope"}; struct sgttyb ttyb; struct utmp utmp; char minusnam[16] = "-"; char homedir[64] = "HOME="; char *envinit[] = {homedir, "PATH=:/bin:/usr/bin", 0}; struct passwd *pwd; struct passwd *getpwnam(); char *strcat(); int setpwent(); char *ttyname(); char *crypt(); char *getpass(); char *rindex(), *index(); 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)) { printf("Login incorrect\n"); goto loop; } } if(chdir(pwd->pw_dir) < 0) { printf("No directory\n"); goto loop; } time(&utmp.ut_time); t = ttyslot(); if(access("/etc/sdloglock", 0) == 0) /* shutdown in progress */ goto nolog; if(access("/etc/loglock",0) == 0 && pwd->pw_gid != 1 && pwd->pw_uid != 0) { nolog: printf("\nNo Logins\n"); exit(0); } if (t>0 && (f = open("/etc/utmp", 1)) >= 0) { lseek(f, (long)(t*sizeof(utmp)), 0); SCPYN(utmp.ut_line, index(ttyn+1, '/')+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); if ((namep = rindex(pwd->pw_shell, '/')) == NULL) namep = pwd->pw_shell; else namep++; strcat(minusnam, namep); alarm(0); umask(02); showmotd(); if(access("/etc/loglock",0) == 0) printf("\nLOGINS DISSABLED\n"); 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); }