1 static char *sccsid = "@(#)login.c 4.14 82/03/15"; 2 /* 3 * login [ name ] 4 * login -r 5 * login -r [ rhost ] 6 */ 7 8 #include <sys/types.h> 9 #include <sgtty.h> 10 #include <utmp.h> 11 #include <signal.h> 12 #include <pwd.h> 13 #include <stdio.h> 14 #include <sys/stat.h> 15 #include <lastlog.h> 16 17 #define SCPYN(a, b) strncpy(a, b, sizeof(a)) 18 19 #define NMAX sizeof(utmp.ut_name) 20 #define LMAX sizeof(utmp.ut_line) 21 22 #define FALSE 0 23 #define TRUE -1 24 25 char nolog[] = "/etc/nologin"; 26 char qlog[] = ".hushlogin"; 27 char securetty[] = "/etc/securetty"; 28 char maildir[30] = "/usr/spool/mail/"; 29 char lastlog[] = "/usr/adm/lastlog"; 30 struct passwd nouser = {"", "nope"}; 31 struct sgttyb ttyb; 32 struct utmp utmp; 33 char minusnam[16] = "-"; 34 35 char homedir[64] = "HOME="; 36 char shell[64] = "SHELL="; 37 char term[64] = "TERM="; 38 char user[20] = "USER="; 39 char *speeds[] = 40 { "0", "50", "75", "110", "134", "150", "200", "300", 41 "600", "1200", "1800", "2400", "4800", "9600", "19200", "38400" }; 42 #define NSPEEDS (sizeof (speeds) / sizeof (speeds[0])) 43 44 char *envinit[] = 45 {homedir, shell, "PATH=:/usr/ucb:/bin:/usr/bin", term, user, 0}; 46 47 struct passwd *pwd; 48 struct passwd *getpwnam(); 49 char *strcat(), *rindex(), *index(); 50 int setpwent(); 51 char *ttyname(); 52 char *crypt(); 53 char *getpass(); 54 char *rindex(); 55 char *stypeof(); 56 extern char **environ; 57 58 #define CTRL(c) ('c'&037) 59 #define CERASE '#' 60 #define CEOT CTRL(d) 61 #define CKILL '@' 62 #define CQUIT 034 /* FS, cntl shift L */ 63 #define CINTR 0177 /* DEL */ 64 #define CSTOP CTRL(s) 65 #define CSTART CTRL(q) 66 #define CBRK 0377 67 struct tchars tc = { 68 CINTR, CQUIT, CSTART, CSTOP, CEOT, CBRK 69 }; 70 struct ltchars ltc = { 71 CTRL(z), CTRL(y), CTRL(r), CTRL(o), CTRL(w), CTRL(v) 72 }; 73 74 int rflag; 75 char rusername[NMAX+1], lusername[NMAX+1]; 76 char rpassword[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 > 0 && !strcmp(argv[1], "-r")) { 99 rflag++; 100 if (argc > 1) 101 rhost = argv[2]; 102 argc = 1; 103 if (rhost) { 104 getstr(rusername, sizeof (rusername), "remuser"); 105 getstr(lusername, sizeof (lusername), "locuser"); 106 } else { 107 getstr(lusername, sizeof (lusername), "Username"); 108 getstr(rpassword, sizeof (rpassword), "Password"); 109 } 110 getstr(term+5, sizeof(term)-5, "Terminal type"); 111 if (rhost == 0) 112 goto normal; 113 if (getuid()) { 114 rflag = 0; 115 goto normal; 116 } 117 setpwent(); 118 pwd = getpwnam(lusername); 119 if (pwd == NULL) { 120 fprintf(stderr, "Login incorrect.\n"); 121 exit(1); 122 } 123 endpwent(); 124 hostf = fopen("/etc/hosts.equiv", "r"); 125 again: 126 if (hostf) { 127 char ahost[32]; 128 while (fgets(ahost, sizeof (ahost), hostf)) { 129 char *user; 130 if (index(ahost, '\n')) 131 *index(ahost, '\n') = 0; 132 user = index(ahost, ' '); 133 if (user) 134 *user++ = 0; 135 if (!strcmp(rhost, ahost) && 136 !strcmp(rusername, user ? user : lusername)) 137 goto normal; 138 } 139 fclose(hostf); 140 } 141 if (first == 1) { 142 first = 0; 143 if (chdir(pwd->pw_dir) < 0) 144 goto again; 145 hostf = fopen(".rhosts", "r"); 146 goto again; 147 } 148 rhost = 0; 149 rflag = -1; 150 } 151 normal: 152 ioctl(0, TIOCLSET, &zero); 153 ioctl(0, TIOCNXCL, 0); 154 gtty(0, &ttyb); 155 if (rflag) { 156 char *cp = index(term, '/'); 157 if (cp) { 158 int i; 159 *cp++ = 0; 160 for (i = 0; i < NSPEEDS; i++) 161 if (!strcmp(speeds[i], cp)) { 162 ttyb.sg_ispeed = ttyb.sg_ospeed = i; 163 break; 164 } 165 } 166 ttyb.sg_flags = ECHO|CRMOD|ANYP|XTABS; 167 } 168 if (rflag == -1) 169 rflag = 0; 170 ttyb.sg_erase = CERASE; 171 ttyb.sg_kill = CKILL; 172 stty(0, &ttyb); 173 ioctl(0, TIOCSETC, &tc); 174 ioctl(0, TIOCSLTC, <c); 175 for (t=3; t<20; t++) 176 close(t); 177 ttyn = ttyname(0); 178 if (ttyn==(char *)0) 179 ttyn = "/dev/tty??"; 180 do { 181 ldisc = 0; 182 ioctl(0, TIOCSETD, &ldisc); 183 invalid = FALSE; 184 SCPYN(utmp.ut_name, ""); 185 if (argc>1) { 186 SCPYN(utmp.ut_name, argv[1]); 187 argc = 0; 188 } 189 if (rflag) 190 strcpy(utmp.ut_name, lusername); 191 else 192 while (utmp.ut_name[0] == '\0') { 193 namep = utmp.ut_name; 194 { char hostname[32]; 195 gethostname(hostname, sizeof (hostname)); 196 printf("%s login: ", hostname); } 197 while ((c = getchar()) != '\n') { 198 if (c == ' ') 199 c = '_'; 200 if (c == EOF) 201 exit(0); 202 if (namep < utmp.ut_name+NMAX) 203 *namep++ = c; 204 } 205 } 206 if (rhost == 0) { 207 setpwent(); 208 if ((pwd = getpwnam(utmp.ut_name)) == NULL) 209 pwd = &nouser; 210 endpwent(); 211 } 212 if (!strcmp(pwd->pw_shell, "/bin/csh")) { 213 ldisc = NTTYDISC; 214 ioctl(0, TIOCSETD, &ldisc); 215 } 216 if (rhost == 0) { 217 if (*pwd->pw_passwd != '\0') { 218 char *pp; 219 nice(-4); 220 if (rflag == 0) 221 pp = getpass("Password:"); 222 else 223 pp = rpassword; 224 namep = crypt(pp,pwd->pw_passwd); 225 nice(4); 226 if (strcmp(namep, pwd->pw_passwd)) 227 invalid = TRUE; 228 } 229 } 230 if (pwd->pw_uid != 0 && (nlfd = fopen(nolog, "r")) > 0) { 231 /* logins are disabled except for root */ 232 while ((c = getc(nlfd)) != EOF) 233 putchar(c); 234 fflush(stdout); 235 sleep(5); 236 exit(0); 237 } 238 if (!invalid && pwd->pw_uid == 0 && 239 !rootterm(ttyn+sizeof("/dev/")-1)) { 240 FILE *console = fopen("/dev/console", "w"); 241 if (console != NULL) { 242 fprintf(console, "\r\nROOT LOGIN REFUSED %s\r\n" 243 , ttyn+sizeof("/dev/")-1 244 ); 245 fclose(console); 246 } 247 invalid = TRUE; 248 } 249 if (invalid) { 250 printf("Login incorrect\n"); 251 if (ttyn[sizeof("/dev/tty")-1] == 'd') { 252 FILE *console = fopen("/dev/console", "w"); 253 if (console != NULL) { 254 fprintf(console, "\r\nBADDIALUP %s %s\r\n" 255 , ttyn+sizeof("/dev/")-1 256 , utmp.ut_name); 257 fclose(console); 258 } 259 } 260 } 261 if (*pwd->pw_shell == '\0') 262 pwd->pw_shell = "/bin/sh"; 263 i = strlen(pwd->pw_shell); 264 if (chdir(pwd->pw_dir) < 0 && !invalid ) { 265 if (chdir("/") < 0) { 266 printf("No directory!\n"); 267 invalid = TRUE; 268 } else { 269 printf("No directory! Logging in with home=/\n"); 270 pwd->pw_dir = "/"; 271 } 272 } 273 if (rflag && invalid) 274 exit(1); 275 } while (invalid); 276 277 278 time(&utmp.ut_time); 279 t = ttyslot(); 280 if (t>0 && (f = open("/etc/utmp", 1)) >= 0) { 281 lseek(f, (long)(t*sizeof(utmp)), 0); 282 SCPYN(utmp.ut_line, rindex(ttyn, '/')+1); 283 write(f, (char *)&utmp, sizeof(utmp)); 284 close(f); 285 } 286 if (t>0 && (f = open("/usr/adm/wtmp", 1)) >= 0) { 287 lseek(f, 0L, 2); 288 write(f, (char *)&utmp, sizeof(utmp)); 289 close(f); 290 } 291 quietlog = FALSE; 292 if (access(qlog, 0) == 0) 293 quietlog = TRUE; 294 if ( !quietlog && (f = open(lastlog, 2)) >= 0 ) { 295 struct lastlog ll; 296 297 lseek(f, (long)pwd->pw_uid * sizeof (struct lastlog), 0); 298 if (read(f, (char *) &ll, sizeof ll) == sizeof ll && 299 ll.ll_time != 0) { 300 printf("Last login: %.*s on %.*s\n" 301 , 24-5 302 , (char *) ctime(&ll.ll_time) 303 , sizeof(ll.ll_line) 304 , ll.ll_line 305 ); 306 } 307 lseek(f, (long)pwd->pw_uid * sizeof (struct lastlog), 0); 308 time(&ll.ll_time); 309 SCPYN(ll.ll_line, rindex(ttyn, '/')+1); 310 write(f, (char *) &ll, sizeof ll); 311 close(f); 312 } 313 chown(ttyn, pwd->pw_uid, pwd->pw_gid); 314 setgid(pwd->pw_gid); 315 inigrp(utmp.ut_name, pwd->pw_gid); 316 setuid(pwd->pw_uid); 317 environ = envinit; 318 strncat(homedir, pwd->pw_dir, sizeof(homedir)-6); 319 strncat(shell, pwd->pw_shell, sizeof(shell)-7); 320 if (rflag == 0) 321 strncat(term, stypeof(ttyn), sizeof(term)-6); 322 strncat(user, pwd->pw_name, sizeof(user)-6); 323 if ((namep = rindex(pwd->pw_shell, '/')) == NULL) 324 namep = pwd->pw_shell; 325 else 326 namep++; 327 strcat(minusnam, namep); 328 alarm(0); 329 umask(022); 330 if (ttyn[sizeof("/dev/tty")-1] == 'd') { 331 FILE *console = fopen("/dev/console", "w"); 332 if (console != NULL) { 333 fprintf(console, "\r\nDIALUP %s %s\r\n" 334 , ttyn+sizeof("/dev/")-1 335 , pwd->pw_name 336 ); 337 fclose(console); 338 } 339 } 340 if ( !quietlog ) { 341 showmotd(); 342 strcat(maildir, pwd->pw_name); 343 if (access(maildir,4)==0) { 344 struct stat statb; 345 stat(maildir, &statb); 346 if (statb.st_size) 347 printf("You have mail.\n"); 348 } 349 } 350 351 signal(SIGQUIT, SIG_DFL); 352 signal(SIGINT, SIG_DFL); 353 signal(SIGTSTP, SIG_IGN); 354 execlp(pwd->pw_shell, minusnam, 0); 355 perror(pwd->pw_shell); 356 printf("No shell\n"); 357 exit(0); 358 } 359 360 int stopmotd; 361 catch() 362 { 363 signal(SIGINT, SIG_IGN); 364 stopmotd++; 365 } 366 367 /* 368 * return true if OK for root to login on this terminal 369 */ 370 rootterm(tty) 371 char *tty; 372 { 373 register FILE *fd; 374 char buf[100]; 375 376 if ((fd = fopen(securetty, "r")) == NULL) 377 return(1); 378 while (fgets(buf, sizeof buf, fd) != NULL) { 379 buf[strlen(buf)-1] = '\0'; 380 if (strcmp(tty, buf) == 0) { 381 fclose(fd); 382 return(1); 383 } 384 } 385 fclose(fd); 386 return(0); 387 } 388 389 showmotd() 390 { 391 FILE *mf; 392 register c; 393 394 signal(SIGINT, catch); 395 if ((mf = fopen("/etc/motd","r")) != NULL) { 396 while ((c = getc(mf)) != EOF && stopmotd == 0) 397 putchar(c); 398 fclose(mf); 399 } 400 signal(SIGINT, SIG_IGN); 401 } 402 403 #undef UNKNOWN 404 #define UNKNOWN "su" 405 406 char * 407 stypeof(ttyid) 408 char *ttyid; 409 { 410 static char typebuf[16]; 411 char buf[50]; 412 register FILE *f; 413 register char *p, *t, *q; 414 415 if (ttyid == NULL) 416 return (UNKNOWN); 417 f = fopen("/etc/ttytype", "r"); 418 if (f == NULL) 419 return (UNKNOWN); 420 /* split off end of name */ 421 for (p = q = ttyid; *p != 0; p++) 422 if (*p == '/') 423 q = p + 1; 424 425 /* scan the file */ 426 while (fgets(buf, sizeof buf, f) != NULL) 427 { 428 for (t=buf; *t!=' ' && *t != '\t'; t++) 429 ; 430 *t++ = 0; 431 while (*t == ' ' || *t == '\t') 432 t++; 433 for (p=t; *p>' '; p++) 434 ; 435 *p = 0; 436 if (strcmp(q,t)==0) { 437 strcpy(typebuf, buf); 438 fclose(f); 439 return (typebuf); 440 } 441 } 442 fclose (f); 443 return (UNKNOWN); 444 } 445 446 getstr(buf, cnt, err) 447 char *buf; 448 int cnt; 449 char *err; 450 { 451 char c; 452 453 do { 454 if (read(0, &c, 1) != 1) 455 exit(1); 456 if (--cnt < 0) { 457 printf("%s too long\r\n", err); 458 exit(1); 459 } 460 *buf++ = c; 461 } while (c != 0); 462 } 463