1 static char *sccsid = "@(#)login.c 4.19 82/11/14"; 2 /* 3 * login [ name ] 4 * login -r 5 */ 6 7 #include <sys/types.h> 8 #include <sgtty.h> 9 #include <utmp.h> 10 #include <signal.h> 11 #include <pwd.h> 12 #include <stdio.h> 13 #include <sys/stat.h> 14 #include <lastlog.h> 15 16 #define SCPYN(a, b) strncpy(a, b, sizeof(a)) 17 18 #define NMAX sizeof(utmp.ut_name) 19 #define LMAX sizeof(utmp.ut_line) 20 21 #define FALSE 0 22 #define TRUE -1 23 24 char nolog[] = "/etc/nologin"; 25 char qlog[] = ".hushlogin"; 26 char securetty[] = "/etc/securetty"; 27 char maildir[30] = "/usr/spool/mail/"; 28 char lastlog[] = "/usr/adm/lastlog"; 29 struct passwd nouser = {"", "nope"}; 30 struct sgttyb ttyb; 31 struct utmp utmp; 32 char minusnam[16] = "-"; 33 34 char homedir[64] = "HOME="; 35 char shell[64] = "SHELL="; 36 char term[64] = "TERM="; 37 char user[20] = "USER="; 38 char *speeds[] = 39 { "0", "50", "75", "110", "134", "150", "200", "300", 40 "600", "1200", "1800", "2400", "4800", "9600", "19200", "38400" }; 41 #define NSPEEDS (sizeof (speeds) / sizeof (speeds[0])) 42 43 char *envinit[] = 44 {homedir, shell, "PATH=:/usr/ucb:/bin:/usr/bin", term, user, 0}; 45 46 struct passwd *pwd; 47 struct passwd *getpwnam(); 48 char *strcat(), *rindex(), *index(); 49 int setpwent(); 50 char *ttyname(); 51 char *crypt(); 52 char *getpass(); 53 char *rindex(); 54 char *stypeof(); 55 extern char **environ; 56 57 #define CTRL(c) ('c'&037) 58 #define CERASE '#' 59 #define CEOT CTRL(d) 60 #define CKILL '@' 61 #define CQUIT 034 /* FS, cntl shift L */ 62 #define CINTR 0177 /* DEL */ 63 #define CSTOP CTRL(s) 64 #define CSTART CTRL(q) 65 #define CBRK 0377 66 struct tchars tc = { 67 CINTR, CQUIT, CSTART, CSTOP, CEOT, CBRK 68 }; 69 struct ltchars ltc = { 70 CTRL(z), CTRL(y), CTRL(r), CTRL(o), CTRL(w), CTRL(v) 71 }; 72 73 int rflag; 74 char rusername[NMAX+1], lusername[NMAX+1]; 75 char rpassword[NMAX+1]; 76 char name[NMAX+1]; 77 char *rhost; 78 79 main(argc, argv) 80 char **argv; 81 { 82 register char *namep; 83 int t, f, c; 84 int invalid; 85 int quietlog; 86 int i; 87 FILE *nlfd; 88 char *ttyn; 89 int ldisc = 0, zero = 0; 90 FILE *hostf; int first = 1; 91 92 alarm(60); 93 signal(SIGQUIT, SIG_IGN); 94 signal(SIGINT, SIG_IGN); 95 nice(-100); 96 nice(20); 97 nice(0); 98 if (argc > 1 && !strcmp(argv[1], "-r")) { 99 rflag++; 100 rhost = argv[2]; 101 argc = 1; 102 getstr(rusername, sizeof (rusername), "remuser"); 103 getstr(lusername, sizeof (lusername), "locuser"); 104 getstr(term+5, sizeof(term)-5, "Terminal type"); 105 if (getuid()) 106 goto abnormal; 107 setpwent(); 108 pwd = getpwnam(lusername); 109 endpwent(); 110 if (pwd == NULL) { 111 if (strcmp(rusername, lusername)) 112 printf("%s: No such user\r\n", lusername); 113 goto abnormal; 114 } 115 hostf = pwd->pw_uid ? fopen("/etc/hosts.equiv", "r") : 0; 116 again: 117 if (hostf) { 118 char ahost[32]; 119 while (fgets(ahost, sizeof (ahost), hostf)) { 120 char *user; 121 if (index(ahost, '\n')) 122 *index(ahost, '\n') = 0; 123 user = index(ahost, ' '); 124 if (user) 125 *user++ = 0; 126 if (!strcmp(rhost, ahost) && 127 !strcmp(rusername, user ? user : lusername)) { 128 fclose(hostf); 129 goto normal; 130 } 131 } 132 fclose(hostf); 133 } 134 if (first == 1) { 135 first = 0; 136 if (chdir(pwd->pw_dir) < 0) 137 goto again; 138 hostf = fopen(".rhosts", "r"); 139 goto again; 140 } 141 abnormal: 142 rhost = 0; 143 rflag = -1; 144 } 145 normal: 146 ioctl(0, TIOCLSET, &zero); 147 ioctl(0, TIOCNXCL, 0); 148 ioctl(0, FIONBIO, &zero); 149 ioctl(0, FIOASYNC, &zero); 150 gtty(0, &ttyb); 151 if (rflag) { 152 char *cp = index(term, '/'); 153 if (cp) { 154 int i; 155 *cp++ = 0; 156 for (i = 0; i < NSPEEDS; i++) 157 if (!strcmp(speeds[i], cp)) { 158 ttyb.sg_ispeed = ttyb.sg_ospeed = i; 159 break; 160 } 161 } 162 ttyb.sg_flags = ECHO|CRMOD|ANYP|XTABS; 163 } 164 ttyb.sg_erase = CERASE; 165 ttyb.sg_kill = CKILL; 166 stty(0, &ttyb); 167 ioctl(0, TIOCSETC, &tc); 168 ioctl(0, TIOCSLTC, <c); 169 for (t=3; t<20; t++) 170 close(t); 171 ttyn = ttyname(0); 172 if (ttyn==(char *)0) 173 ttyn = "/dev/tty??"; 174 do { 175 ldisc = 0; 176 ioctl(0, TIOCSETD, &ldisc); 177 invalid = FALSE; 178 SCPYN(utmp.ut_name, ""); 179 if (argc>1) { 180 SCPYN(utmp.ut_name, argv[1]); 181 argc = 0; 182 } 183 if (rflag) { 184 strcpy(utmp.ut_name, lusername); 185 if (rflag == -1) 186 rflag = 0; 187 } else 188 while (utmp.ut_name[0] == '\0') { 189 namep = utmp.ut_name; 190 { char hostname[32]; 191 gethostname(hostname, sizeof (hostname)); 192 printf("%s login: ", hostname); } 193 while ((c = getchar()) != '\n') { 194 if (c == ' ') 195 c = '_'; 196 if (c == EOF) 197 exit(0); 198 if (namep < utmp.ut_name+NMAX) 199 *namep++ = c; 200 } 201 } 202 if (rhost == 0) { 203 setpwent(); 204 if ((pwd = getpwnam(utmp.ut_name)) == NULL) 205 pwd = &nouser; 206 endpwent(); 207 } 208 if (!strcmp(pwd->pw_shell, "/bin/csh")) { 209 ldisc = NTTYDISC; 210 ioctl(0, TIOCSETD, &ldisc); 211 } 212 if (rhost == 0) { 213 if (*pwd->pw_passwd != '\0') { 214 char *pp; 215 nice(-4); 216 if (rflag == 0) 217 pp = getpass("Password:"); 218 else 219 pp = rpassword; 220 namep = crypt(pp,pwd->pw_passwd); 221 nice(4); 222 if (strcmp(namep, pwd->pw_passwd)) 223 invalid = TRUE; 224 } 225 } 226 if (pwd->pw_uid != 0 && (nlfd = fopen(nolog, "r")) > 0) { 227 /* logins are disabled except for root */ 228 while ((c = getc(nlfd)) != EOF) 229 putchar(c); 230 fflush(stdout); 231 sleep(5); 232 exit(0); 233 } 234 if (!invalid && pwd->pw_uid == 0 && 235 !rootterm(ttyn+sizeof("/dev/")-1)) { 236 logerr("ROOT LOGIN REFUSED %s", 237 ttyn+sizeof("/dev/")-1); 238 invalid = TRUE; 239 } 240 if (invalid) { 241 printf("Login incorrect\n"); 242 if (ttyn[sizeof("/dev/tty")-1] == 'd') 243 logerr("BADDIALUP %s %s\n", 244 ttyn+sizeof("/dev/")-1, utmp.ut_name); 245 } 246 if (*pwd->pw_shell == '\0') 247 pwd->pw_shell = "/bin/sh"; 248 i = strlen(pwd->pw_shell); 249 if (chdir(pwd->pw_dir) < 0 && !invalid ) { 250 if (chdir("/") < 0) { 251 printf("No directory!\n"); 252 invalid = TRUE; 253 } else { 254 printf("No directory! Logging in with home=/\n"); 255 pwd->pw_dir = "/"; 256 } 257 } 258 if (rflag && invalid) 259 exit(1); 260 } while (invalid); 261 262 263 time(&utmp.ut_time); 264 t = ttyslot(); 265 if (t>0 && (f = open("/etc/utmp", 1)) >= 0) { 266 lseek(f, (long)(t*sizeof(utmp)), 0); 267 SCPYN(utmp.ut_line, rindex(ttyn, '/')+1); 268 write(f, (char *)&utmp, sizeof(utmp)); 269 close(f); 270 } 271 if (t>0 && (f = open("/usr/adm/wtmp", 1)) >= 0) { 272 lseek(f, 0L, 2); 273 write(f, (char *)&utmp, sizeof(utmp)); 274 close(f); 275 } 276 quietlog = 0; 277 if (access(qlog, 0) == 0) 278 quietlog = 1; 279 if ((f = open(lastlog, 2)) >= 0) { 280 struct lastlog ll; 281 282 lseek(f, (long)pwd->pw_uid * sizeof (struct lastlog), 0); 283 if (read(f, (char *) &ll, sizeof ll) == sizeof ll && 284 ll.ll_time != 0) { 285 if (quietlog == 0) 286 printf("Last login: %.*s on %.*s\n" 287 , 24-5 288 , (char *) ctime(&ll.ll_time) 289 , sizeof(ll.ll_line) 290 , ll.ll_line 291 ); 292 } 293 lseek(f, (long)pwd->pw_uid * sizeof (struct lastlog), 0); 294 time(&ll.ll_time); 295 SCPYN(ll.ll_line, rindex(ttyn, '/')+1); 296 write(f, (char *) &ll, sizeof ll); 297 close(f); 298 } 299 chown(ttyn, pwd->pw_uid, pwd->pw_gid); 300 chmod(ttyn, 622); 301 setgid(pwd->pw_gid); 302 strncpy(name, utmp.ut_name, NMAX); 303 name[NMAX] = '\0'; 304 initgroups(name, pwd->pw_gid); 305 setuid(pwd->pw_uid); 306 environ = envinit; 307 strncat(homedir, pwd->pw_dir, sizeof(homedir)-6); 308 strncat(shell, pwd->pw_shell, sizeof(shell)-7); 309 if (term[strlen("TERM=")] == 0) 310 strncat(term, stypeof(ttyn), sizeof(term)-6); 311 strncat(user, pwd->pw_name, sizeof(user)-6); 312 if ((namep = rindex(pwd->pw_shell, '/')) == NULL) 313 namep = pwd->pw_shell; 314 else 315 namep++; 316 strcat(minusnam, namep); 317 alarm(0); 318 umask(022); 319 if (ttyn[sizeof("/dev/tty")-1] == 'd') 320 logerr("DIALUP %s %s\n", ttyn+sizeof("/dev/")-1, pwd->pw_name); 321 if (!quietlog) { 322 showmotd(); 323 strcat(maildir, pwd->pw_name); 324 if (access(maildir,4)==0) { 325 struct stat statb; 326 stat(maildir, &statb); 327 if (statb.st_size) 328 printf("You have mail.\n"); 329 } 330 } 331 332 signal(SIGQUIT, SIG_DFL); 333 signal(SIGINT, SIG_DFL); 334 signal(SIGTSTP, SIG_IGN); 335 execlp(pwd->pw_shell, minusnam, 0); 336 perror(pwd->pw_shell); 337 printf("No shell\n"); 338 exit(0); 339 } 340 341 int stopmotd; 342 catch() 343 { 344 345 signal(SIGINT, SIG_IGN); 346 stopmotd++; 347 } 348 349 rootterm(tty) 350 char *tty; 351 { 352 register FILE *fd; 353 char buf[100]; 354 355 if (rflag) 356 return(1); 357 if ((fd = fopen(securetty, "r")) == NULL) 358 return(1); 359 while (fgets(buf, sizeof buf, fd) != NULL) { 360 buf[strlen(buf)-1] = '\0'; 361 if (strcmp(tty, buf) == 0) { 362 fclose(fd); 363 return(1); 364 } 365 } 366 fclose(fd); 367 return(0); 368 } 369 370 showmotd() 371 { 372 FILE *mf; 373 register c; 374 375 signal(SIGINT, catch); 376 if ((mf = fopen("/etc/motd","r")) != NULL) { 377 while ((c = getc(mf)) != EOF && stopmotd == 0) 378 putchar(c); 379 fclose(mf); 380 } 381 signal(SIGINT, SIG_IGN); 382 } 383 384 #undef UNKNOWN 385 #define UNKNOWN "su" 386 387 char * 388 stypeof(ttyid) 389 char *ttyid; 390 { 391 static char typebuf[16]; 392 char buf[50]; 393 register FILE *f; 394 register char *p, *t, *q; 395 396 if (ttyid == NULL) 397 return (UNKNOWN); 398 f = fopen("/etc/ttytype", "r"); 399 if (f == NULL) 400 return (UNKNOWN); 401 /* split off end of name */ 402 for (p = q = ttyid; *p != 0; p++) 403 if (*p == '/') 404 q = p + 1; 405 406 /* scan the file */ 407 while (fgets(buf, sizeof buf, f) != NULL) 408 { 409 for (t=buf; *t!=' ' && *t != '\t'; t++) 410 ; 411 *t++ = 0; 412 while (*t == ' ' || *t == '\t') 413 t++; 414 for (p=t; *p>' '; p++) 415 ; 416 *p = 0; 417 if (strcmp(q,t)==0) { 418 strcpy(typebuf, buf); 419 fclose(f); 420 return (typebuf); 421 } 422 } 423 fclose (f); 424 return (UNKNOWN); 425 } 426 427 getstr(buf, cnt, err) 428 char *buf; 429 int cnt; 430 char *err; 431 { 432 char c; 433 434 do { 435 if (read(0, &c, 1) != 1) 436 exit(1); 437 if (--cnt < 0) { 438 printf("%s too long\r\n", err); 439 exit(1); 440 } 441 *buf++ = c; 442 } while (c != 0); 443 } 444 445 logerr(fmt, a1, a2, a3) 446 char *fmt, *a1, *a2, *a3; 447 { 448 449 } 450