1 #ifndef lint 2 static char sccsid[] = "@(#)rlogind.c 4.17 83/06/24"; 3 #endif 4 5 #include <stdio.h> 6 #include <sys/types.h> 7 #include <sys/stat.h> 8 #include <sys/socket.h> 9 10 #include <netinet/in.h> 11 12 #include <errno.h> 13 #include <pwd.h> 14 #include <wait.h> 15 #include <signal.h> 16 #include <sgtty.h> 17 #include <stdio.h> 18 #include <netdb.h> 19 20 extern errno; 21 int reapchild(); 22 struct passwd *getpwnam(); 23 char *crypt(), *rindex(), *index(), *malloc(), *ntoa(); 24 struct sockaddr_in sin = { AF_INET }; 25 /* 26 * remote login server: 27 * remuser\0 28 * locuser\0 29 * terminal type\0 30 * data 31 */ 32 main(argc, argv) 33 int argc; 34 char **argv; 35 { 36 int f, options = 0; 37 struct sockaddr_in from; 38 struct servent *sp; 39 40 sp = getservbyname("login", "tcp"); 41 if (sp == 0) { 42 fprintf(stderr, "rlogind: tcp/rlogin: unknown service\n"); 43 exit(1); 44 } 45 #ifndef DEBUG 46 if (fork()) 47 exit(0); 48 for (f = 0; f < 10; f++) 49 (void) close(f); 50 (void) open("/", 0); 51 (void) dup2(0, 1); 52 (void) dup2(0, 2); 53 { int tt = open("/dev/tty", 2); 54 if (tt > 0) { 55 ioctl(tt, TIOCNOTTY, 0); 56 close(tt); 57 } 58 } 59 #endif 60 sin.sin_port = sp->s_port; 61 argc--, argv++; 62 if (argc > 0 && !strcmp(argv[0], "-d")) { 63 options |= SO_DEBUG; 64 argc--, argv++; 65 } 66 if (argc > 0) { 67 int port = atoi(argv[0]); 68 69 if (port < 0) { 70 fprintf(stderr, "%s: bad port #\n", argv[0]); 71 exit(1); 72 } 73 sin.sin_port = htons((u_short)port); 74 argv++, argc--; 75 } 76 f = socket(AF_INET, SOCK_STREAM, 0, 0); 77 if (f < 0) { 78 perror("rlogind: socket"); 79 exit(1); 80 } 81 if (options & SO_DEBUG) 82 if (setsockopt(f, SOL_SOCKET, SO_DEBUG, 0, 0) < 0) 83 perror("rlogind: setsockopt (SO_DEBUG)"); 84 if (setsockopt(f, SOL_SOCKET, SO_KEEPALIVE, 0, 0) < 0) 85 perror("rlogind: setsockopt (SO_KEEPALIVE)"); 86 if (bind(f, &sin, sizeof (sin), 0) < 0) { 87 perror("rlogind: bind"); 88 exit(1); 89 } 90 signal(SIGCHLD, reapchild); 91 listen(f, 10); 92 for (;;) { 93 int s, len = sizeof (from); 94 95 s = accept(f, &from, &len, 0); 96 if (s < 0) { 97 if (errno == EINTR) 98 continue; 99 perror("rlogind: accept"); 100 continue; 101 } 102 if (fork() == 0) { 103 signal(SIGCHLD, SIG_IGN); 104 close(f); 105 doit(s, &from); 106 } 107 close(s); 108 } 109 } 110 111 reapchild() 112 { 113 union wait status; 114 115 while (wait3(&status, WNOHANG, 0) > 0) 116 ; 117 } 118 119 char locuser[32], remuser[32]; 120 char buf[BUFSIZ]; 121 int child; 122 int cleanup(); 123 int netf; 124 extern errno; 125 char *line; 126 127 doit(f, fromp) 128 int f; 129 struct sockaddr_in *fromp; 130 { 131 char c; 132 int i, p, cc, t, pid; 133 int stop = TIOCPKT_DOSTOP; 134 register struct hostent *hp; 135 136 alarm(60); 137 read(f, &c, 1); 138 if (c != 0) 139 exit(1); 140 alarm(0); 141 fromp->sin_port = htons((u_short)fromp->sin_port); 142 hp = gethostbyaddr(&fromp->sin_addr, sizeof (struct in_addr), 143 fromp->sin_family); 144 if (hp == 0) { 145 char buf[BUFSIZ], *cp = (char *)&fromp->sin_addr; 146 147 fatal(f, sprintf(buf, "Host name for your address (%s) unknown", 148 ntoa(fromp->sin_addr))); 149 } 150 if (fromp->sin_family != AF_INET || 151 fromp->sin_port >= IPPORT_RESERVED || 152 hp == 0) 153 fatal(f, "Permission denied"); 154 write(f, "", 1); 155 for (c = 'p'; c <= 's'; c++) { 156 struct stat stb; 157 line = "/dev/ptyXX"; 158 line[strlen("/dev/pty")] = c; 159 line[strlen("/dev/ptyp")] = '0'; 160 if (stat(line, &stb) < 0) 161 break; 162 for (i = 0; i < 16; i++) { 163 line[strlen("/dev/ptyp")] = "0123456789abcdef"[i]; 164 p = open(line, 2); 165 if (p > 0) 166 goto gotpty; 167 } 168 } 169 fatal(f, "All network ports in use"); 170 /*NOTREACHED*/ 171 gotpty: 172 dup2(f, 0); 173 line[strlen("/dev/")] = 't'; 174 #ifdef DEBUG 175 { int tt = open("/dev/tty", 2); 176 if (tt > 0) { 177 ioctl(tt, TIOCNOTTY, 0); 178 close(tt); 179 } 180 } 181 #endif 182 t = open(line, 2); 183 if (t < 0) 184 fatalperror(f, line, errno); 185 { struct sgttyb b; 186 gtty(t, &b); b.sg_flags = RAW|ANYP; stty(t, &b); 187 } 188 pid = fork(); 189 if (pid < 0) 190 fatalperror(f, "", errno); 191 if (pid) { 192 char pibuf[1024], fibuf[1024], *pbp, *fbp; 193 int pcc = 0, fcc = 0, on = 1; 194 /* FILE *console = fopen("/dev/console", "w"); */ 195 /* setbuf(console, 0); */ 196 197 /* fprintf(console, "f %d p %d\r\n", f, p); */ 198 ioctl(f, FIONBIO, &on); 199 ioctl(p, FIONBIO, &on); 200 ioctl(p, TIOCPKT, &on); 201 signal(SIGTSTP, SIG_IGN); 202 signal(SIGCHLD, cleanup); 203 for (;;) { 204 int ibits = 0, obits = 0; 205 206 if (fcc) 207 obits |= (1<<p); 208 else 209 ibits |= (1<<f); 210 if (pcc >= 0) 211 if (pcc) 212 obits |= (1<<f); 213 else 214 ibits |= (1<<p); 215 if (fcc < 0 && pcc < 0) 216 break; 217 /* fprintf(console, "ibits from %d obits from %d\r\n", ibits, obits); */ 218 select(16, &ibits, &obits, 0, 0, 0); 219 /* fprintf(console, "ibits %d obits %d\r\n", ibits, obits); */ 220 if (ibits == 0 && obits == 0) { 221 sleep(5); 222 continue; 223 } 224 if (ibits & (1<<f)) { 225 fcc = read(f, fibuf, sizeof (fibuf)); 226 /* fprintf(console, "%d from f\r\n", fcc); */ 227 if (fcc < 0 && errno == EWOULDBLOCK) 228 fcc = 0; 229 else { 230 if (fcc <= 0) 231 break; 232 fbp = fibuf; 233 } 234 } 235 if (ibits & (1<<p)) { 236 pcc = read(p, pibuf, sizeof (pibuf)); 237 /* fprintf(console, "%d from p, buf[0] %x, errno %d\r\n", pcc, buf[0], errno); */ 238 pbp = pibuf; 239 if (pcc < 0 && errno == EWOULDBLOCK) 240 pcc = 0; 241 else if (pcc <= 0) 242 pcc = -1; 243 else if (pibuf[0] == 0) 244 pbp++, pcc--; 245 else { 246 if (pibuf[0]&(TIOCPKT_FLUSHWRITE| 247 TIOCPKT_NOSTOP| 248 TIOCPKT_DOSTOP)) { 249 int nstop = pibuf[0] & 250 (TIOCPKT_NOSTOP| 251 TIOCPKT_DOSTOP); 252 if (nstop) 253 stop = nstop; 254 pibuf[0] |= nstop; 255 send(f,&pibuf[0],1,MSG_OOB); 256 } 257 pcc = 0; 258 } 259 } 260 if ((obits & (1<<f)) && pcc > 0) { 261 cc = write(f, pbp, pcc); 262 /* fprintf(console, "%d of %d to f\r\n", cc, pcc); */ 263 if (cc > 0) { 264 pcc -= cc; 265 pbp += cc; 266 } 267 } 268 if ((obits & (1<<p)) && fcc > 0) { 269 cc = write(p, fbp, fcc); 270 /* fprintf(console, "%d of %d to p\r\n", cc, fcc); */ 271 if (cc > 0) { 272 fcc -= cc; 273 fbp += cc; 274 } 275 } 276 } 277 cleanup(); 278 } 279 close(f); 280 close(p); 281 dup2(t, 0); 282 dup2(t, 1); 283 dup2(t, 2); 284 close(t); 285 execl("/bin/login", "login", "-r", hp->h_name, 0); 286 fatalperror(2, "/bin/login", errno); 287 /*NOTREACHED*/ 288 } 289 290 cleanup() 291 { 292 293 rmut(); 294 vhangup(); /* XXX */ 295 shutdown(netf, 2); 296 kill(0, SIGKILL); 297 exit(1); 298 } 299 300 fatal(f, msg) 301 int f; 302 char *msg; 303 { 304 char buf[BUFSIZ]; 305 306 buf[0] = '\01'; /* error indicator */ 307 (void) sprintf(buf + 1, "rlogind: %s.\n", msg); 308 (void) write(f, buf, strlen(buf)); 309 exit(1); 310 } 311 312 fatalperror(f, msg, errno) 313 int f; 314 char *msg; 315 int errno; 316 { 317 char buf[BUFSIZ]; 318 extern char *sys_errlist[]; 319 320 (void) sprintf(buf, "%s: %s", msg, sys_errlist[errno]); 321 fatal(f, buf); 322 } 323 324 #include <utmp.h> 325 326 struct utmp wtmp; 327 char wtmpf[] = "/usr/adm/wtmp"; 328 char utmp[] = "/etc/utmp"; 329 #define SCPYN(a, b) strncpy(a, b, sizeof(a)) 330 #define SCMPN(a, b) strncmp(a, b, sizeof(a)) 331 332 rmut() 333 { 334 register f; 335 int found = 0; 336 337 f = open(utmp, 2); 338 if (f >= 0) { 339 while(read(f, (char *)&wtmp, sizeof(wtmp)) == sizeof(wtmp)) { 340 if (SCMPN(wtmp.ut_line, line+5) || wtmp.ut_name[0]==0) 341 continue; 342 lseek(f, -(long)sizeof(wtmp), 1); 343 SCPYN(wtmp.ut_name, ""); 344 SCPYN(wtmp.ut_host, ""); 345 time(&wtmp.ut_time); 346 write(f, (char *)&wtmp, sizeof(wtmp)); 347 found++; 348 } 349 close(f); 350 } 351 if (found) { 352 f = open(wtmpf, 1); 353 if (f >= 0) { 354 SCPYN(wtmp.ut_line, line+5); 355 SCPYN(wtmp.ut_name, ""); 356 SCPYN(wtmp.ut_host, ""); 357 time(&wtmp.ut_time); 358 lseek(f, (long)0, 2); 359 write(f, (char *)&wtmp, sizeof(wtmp)); 360 close(f); 361 } 362 } 363 chmod(line, 0666); 364 chown(line, 0, 0); 365 line[strlen("/dev/")] = 'p'; 366 chmod(line, 0666); 367 chown(line, 0, 0); 368 } 369 370 /* 371 * Convert network-format internet address 372 * to base 256 d.d.d.d representation. 373 */ 374 char * 375 ntoa(in) 376 struct in_addr in; 377 { 378 static char b[18]; 379 register char *p; 380 381 p = (char *)∈ 382 #define UC(b) (((int)b)&0xff) 383 sprintf(b, "%d.%d.%d.%d", UC(p[0]), UC(p[1]), UC(p[2]), UC(p[3])); 384 return (b); 385 } 386