slirp/misc.c

   1 /*
   2  * Copyright (c) 1995 Danny Gasparovski.
   3  *
   4  * Please read the file COPYRIGHT for the
   5  * terms and conditions of the copyright.
   6  */
   7
   8 #include <slirp.h>
   9 #include <libslirp.h>
  10
  11 #include "monitor.h"
  12
  13 u_int curtime, time_fasttimo, last_slowtimo;
  14
  15 /*
  16  * Get our IP address and put it in our_addr
  17  */
  18 void
  19 getouraddr(void)
  20 {
  21         char buff[256];
  22         struct hostent *he = NULL;
  23
  24         if (gethostname(buff,256) == 0)
  25             he = gethostbyname(buff);
  26         if (he)
  27             our_addr = *(struct in_addr *)he->h_addr;
  28         if (our_addr.s_addr == 0)
  29             our_addr.s_addr = loopback_addr.s_addr;
  30 }
  31
  32 struct quehead {
  33         struct quehead *qh_link;
  34         struct quehead *qh_rlink;
  35 };
  36
  37 inline void
  38 insque(void *a, void *b)
  39 {
  40         register struct quehead *element = (struct quehead *) a;
  41         register struct quehead *head = (struct quehead *) b;
  42         element->qh_link = head->qh_link;
  43         head->qh_link = (struct quehead *)element;
  44         element->qh_rlink = (struct quehead *)head;
  45         ((struct quehead *)(element->qh_link))->qh_rlink
  46         = (struct quehead *)element;
  47 }
  48
  49 inline void
  50 remque(void *a)
  51 {
  52   register struct quehead *element = (struct quehead *) a;
  53   ((struct quehead *)(element->qh_link))->qh_rlink = element->qh_rlink;
  54   ((struct quehead *)(element->qh_rlink))->qh_link = element->qh_link;
  55   element->qh_rlink = NULL;
  56 }
  57
  58 int add_exec(struct ex_list **ex_ptr, int do_pty, char *exec,
  59              struct in_addr addr, int port)
  60 {
  61         struct ex_list *tmp_ptr;
  62
  63         /* First, check if the port is "bound" */
  64         for (tmp_ptr = *ex_ptr; tmp_ptr; tmp_ptr = tmp_ptr->ex_next) {
  65                 if (port == tmp_ptr->ex_fport &&
  66                     addr.s_addr == tmp_ptr->ex_addr.s_addr)
  67                         return -1;
  68         }
  69
  70         tmp_ptr = *ex_ptr;
  71         *ex_ptr = (struct ex_list *)malloc(sizeof(struct ex_list));
  72         (*ex_ptr)->ex_fport = port;
  73         (*ex_ptr)->ex_addr = addr;
  74         (*ex_ptr)->ex_pty = do_pty;
  75         (*ex_ptr)->ex_exec = (do_pty == 3) ? exec : strdup(exec);
  76         (*ex_ptr)->ex_next = tmp_ptr;
  77         return 0;
  78 }
  79
  80 #ifndef HAVE_STRERROR
  81
  82 /*
  83  * For systems with no strerror
  84  */
  85
  86 extern int sys_nerr;
  87 extern char *sys_errlist[];
  88
  89 char *
  90 strerror(error)
  91         int error;
  92 {
  93         if (error < sys_nerr)
  94            return sys_errlist[error];
  95         else
  96            return "Unknown error.";
  97 }
  98
  99 #endif
 100
 101
 102 #ifdef _WIN32
 103
 104 int
 105 fork_exec(struct socket *so, const char *ex, int do_pty)
 106 {
 107     /* not implemented */
 108     return 0;
 109 }
 110
 111 #else
 112
 113 /*
 114  * XXX This is ugly
 115  * We create and bind a socket, then fork off to another
 116  * process, which connects to this socket, after which we
 117  * exec the wanted program.  If something (strange) happens,
 118  * the accept() call could block us forever.
 119  *
 120  * do_pty = 0   Fork/exec inetd style
 121  * do_pty = 1   Fork/exec using slirp.telnetd
 122  * do_ptr = 2   Fork/exec using pty
 123  */
 124 int
 125 fork_exec(struct socket *so, const char *ex, int do_pty)
 126 {
 127         int s;
 128         struct sockaddr_in addr;
 129         socklen_t addrlen = sizeof(addr);
 130         int opt;
 131         int master = -1;
 132         const char *argv[256];
 133         /* don't want to clobber the original */
 134         char *bptr;
 135         const char *curarg;
 136         int c, i, ret;
 137
 138         DEBUG_CALL("fork_exec");
 139         DEBUG_ARG("so = %lx", (long)so);
 140         DEBUG_ARG("ex = %lx", (long)ex);
 141         DEBUG_ARG("do_pty = %lx", (long)do_pty);
 142
 143         if (do_pty == 2) {
 144                 return 0;
 145         } else {
 146                 addr.sin_family = AF_INET;
 147                 addr.sin_port = 0;
 148                 addr.sin_addr.s_addr = INADDR_ANY;
 149
 150                 if ((s = socket(AF_INET, SOCK_STREAM, 0)) < 0 ||
 151                     bind(s, (struct sockaddr *)&addr, addrlen) < 0 ||
 152                     listen(s, 1) < 0) {
 153                         lprint("Error: inet socket: %s\n", strerror(errno));
 154                         closesocket(s);
 155
 156                         return 0;
 157                 }
 158         }
 159
 160         switch(fork()) {
 161          case -1:
 162                 lprint("Error: fork failed: %s\n", strerror(errno));
 163                 close(s);
 164                 if (do_pty == 2)
 165                    close(master);
 166                 return 0;
 167
 168          case 0:
 169                 /* Set the DISPLAY */
 170                 if (do_pty == 2) {
 171                         (void) close(master);
 172 #ifdef TIOCSCTTY /* XXXXX */
 173                         (void) setsid();
 174                         ioctl(s, TIOCSCTTY, (char *)NULL);
 175 #endif
 176                 } else {
 177                         getsockname(s, (struct sockaddr *)&addr, &addrlen);
 178                         close(s);
 179                         /*
 180                          * Connect to the socket
 181                          * XXX If any of these fail, we're in trouble!
 182                          */
 183                         s = socket(AF_INET, SOCK_STREAM, 0);
 184                         addr.sin_addr = loopback_addr;
 185                         do {
 186                             ret = connect(s, (struct sockaddr *)&addr, addrlen);
 187                         } while (ret < 0 && errno == EINTR);
 188                 }
 189
 190                 dup2(s, 0);
 191                 dup2(s, 1);
 192                 dup2(s, 2);
 193                 for (s = getdtablesize() - 1; s >= 3; s--)
 194                    close(s);
 195
 196                 i = 0;
 197                 bptr = strdup(ex); /* No need to free() this */
 198                 if (do_pty == 1) {
 199                         /* Setup "slirp.telnetd -x" */
 200                         argv[i++] = "slirp.telnetd";
 201                         argv[i++] = "-x";
 202                         argv[i++] = bptr;
 203                 } else
 204                    do {
 205                         /* Change the string into argv[] */
 206                         curarg = bptr;
 207                         while (*bptr != ' ' && *bptr != (char)0)
 208                            bptr++;
 209                         c = *bptr;
 210                         *bptr++ = (char)0;
 211                         argv[i++] = strdup(curarg);
 212                    } while (c);
 213
 214                 argv[i] = NULL;
 215                 execvp(argv[0], (char **)argv);
 216
 217                 /* Ooops, failed, let's tell the user why */
 218                   {
 219                           char buff[256];
 220
 221                           snprintf(buff, sizeof(buff),
 222                                    "Error: execvp of %s failed: %s\n",
 223                                    argv[0], strerror(errno));
 224                           write(2, buff, strlen(buff)+1);
 225                   }
 226                 close(0); close(1); close(2); /* XXX */
 227                 exit(1);
 228
 229          default:
 230                 if (do_pty == 2) {
 231                         close(s);
 232                         so->s = master;
 233                 } else {
 234                         /*
 235                          * XXX this could block us...
 236                          * XXX Should set a timer here, and if accept() doesn't
 237                          * return after X seconds, declare it a failure
 238                          * The only reason this will block forever is if socket()
 239                          * of connect() fail in the child process
 240                          */
 241                         do {
 242                             so->s = accept(s, (struct sockaddr *)&addr, &addrlen);
 243                         } while (so->s < 0 && errno == EINTR);
 244                         closesocket(s);
 245                         opt = 1;
 246                         setsockopt(so->s,SOL_SOCKET,SO_REUSEADDR,(char *)&opt,sizeof(int));
 247                         opt = 1;
 248                         setsockopt(so->s,SOL_SOCKET,SO_OOBINLINE,(char *)&opt,sizeof(int));
 249                 }
 250                 fd_nonblock(so->s);
 251
 252                 /* Append the telnet options now */
 253                 if (so->so_m != NULL && do_pty == 1)  {
 254                         sbappend(so, so->so_m);
 255                         so->so_m = NULL;
 256                 }
 257
 258                 return 1;
 259         }
 260 }
 261 #endif
 262
 263 #ifndef HAVE_STRDUP
 264 char *
 265 strdup(str)
 266         const char *str;
 267 {
 268         char *bptr;
 269
 270         bptr = (char *)malloc(strlen(str)+1);
 271         strcpy(bptr, str);
 272
 273         return bptr;
 274 }
 275 #endif
 276
 277 #include "monitor.h"
 278
 279 void lprint(const char *format, ...)
 280 {
 281     va_list args;
 282
 283     va_start(args, format);
 284     monitor_vprintf(cur_mon, format, args);
 285     va_end(args);
 286 }
 287
 288 #ifdef BAD_SPRINTF
 289
 290 #undef vsprintf
 291 #undef sprintf
 292
 293 /*
 294  * Some BSD-derived systems have a sprintf which returns char *
 295  */
 296
 297 int
 298 vsprintf_len(string, format, args)
 299         char *string;
 300         const char *format;
 301         va_list args;
 302 {
 303         vsprintf(string, format, args);
 304         return strlen(string);
 305 }
 306
 307 int
 308 #ifdef __STDC__
 309 sprintf_len(char *string, const char *format, ...)
 310 #else
 311 sprintf_len(va_alist) va_dcl
 312 #endif
 313 {
 314         va_list args;
 315 #ifdef __STDC__
 316         va_start(args, format);
 317 #else
 318         char *string;
 319         char *format;
 320         va_start(args);
 321         string = va_arg(args, char *);
 322         format = va_arg(args, char *);
 323 #endif
 324         vsprintf(string, format, args);
 325         return strlen(string);
 326 }
 327
 328 #endif
 329
 330 void
 331 u_sleep(int usec)
 332 {
 333         struct timeval t;
 334         fd_set fdset;
 335
 336         FD_ZERO(&fdset);
 337
 338         t.tv_sec = 0;
 339         t.tv_usec = usec * 1000;
 340
 341         select(0, &fdset, &fdset, &fdset, &t);
 342 }
 343
 344 /*
 345  * Set fd blocking and non-blocking
 346  */
 347
 348 void
 349 fd_nonblock(int fd)
 350 {
 351 #ifdef FIONBIO
 352 #ifdef _WIN32
 353         unsigned long opt = 1;
 354 #else
 355         int opt = 1;
 356 #endif
 357
 358         ioctlsocket(fd, FIONBIO, &opt);
 359 #else
 360         int opt;
 361
 362         opt = fcntl(fd, F_GETFL, 0);
 363         opt |= O_NONBLOCK;
 364         fcntl(fd, F_SETFL, opt);
 365 #endif
 366 }
 367
 368 void
 369 fd_block(int fd)
 370 {
 371 #ifdef FIONBIO
 372 #ifdef _WIN32
 373         unsigned long opt = 0;
 374 #else
 375         int opt = 0;
 376 #endif
 377
 378         ioctlsocket(fd, FIONBIO, &opt);
 379 #else
 380         int opt;
 381
 382         opt = fcntl(fd, F_GETFL, 0);
 383         opt &= ~O_NONBLOCK;
 384         fcntl(fd, F_SETFL, opt);
 385 #endif
 386 }
 387
 388 void slirp_connection_info(Monitor *mon)
 389 {
 390     const char * const tcpstates[] = {
 391         [TCPS_CLOSED]       = "CLOSED",
 392         [TCPS_LISTEN]       = "LISTEN",
 393         [TCPS_SYN_SENT]     = "SYN_SENT",
 394         [TCPS_SYN_RECEIVED] = "SYN_RCVD",
 395         [TCPS_ESTABLISHED]  = "ESTABLISHED",
 396         [TCPS_CLOSE_WAIT]   = "CLOSE_WAIT",
 397         [TCPS_FIN_WAIT_1]   = "FIN_WAIT_1",
 398         [TCPS_CLOSING]      = "CLOSING",
 399         [TCPS_LAST_ACK]     = "LAST_ACK",
 400         [TCPS_FIN_WAIT_2]   = "FIN_WAIT_2",
 401         [TCPS_TIME_WAIT]    = "TIME_WAIT",
 402     };
 403     struct in_addr dst_addr;
 404     struct sockaddr_in src;
 405     socklen_t src_len;
 406     uint16_t dst_port;
 407     struct socket *so;
 408     const char *state;
 409     char buf[20];
 410     int n;
 411
 412     monitor_printf(mon, "  Protocol[State]    FD  Source Address  Port   "
 413                         "Dest. Address  Port RecvQ SendQ\n");
 414
 415     for (so = tcb.so_next; so != &tcb; so = so->so_next) {
 416         if (so->so_state & SS_HOSTFWD) {
 417             state = "HOST_FORWARD";
 418         } else if (so->so_tcpcb) {
 419             state = tcpstates[so->so_tcpcb->t_state];
 420         } else {
 421             state = "NONE";
 422         }
 423         if (so->so_state & (SS_HOSTFWD | SS_INCOMING)) {
 424             src_len = sizeof(src);
 425             getsockname(so->s, (struct sockaddr *)&src, &src_len);
 426             dst_addr = so->so_laddr;
 427             dst_port = so->so_lport;
 428         } else {
 429             src.sin_addr = so->so_laddr;
 430             src.sin_port = so->so_lport;
 431             dst_addr = so->so_faddr;
 432             dst_port = so->so_fport;
 433         }
 434         n = snprintf(buf, sizeof(buf), "  TCP[%s]", state);
 435         memset(&buf[n], ' ', 19 - n);
 436         buf[19] = 0;
 437         monitor_printf(mon, "%s %3d %15s %5d ", buf, so->s,
 438                        src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*",
 439                        ntohs(src.sin_port));
 440         monitor_printf(mon, "%15s %5d %5d %5d\n",
 441                        inet_ntoa(dst_addr), ntohs(dst_port),
 442                        so->so_rcv.sb_cc, so->so_snd.sb_cc);
 443     }
 444
 445     for (so = udb.so_next; so != &udb; so = so->so_next) {
 446         if (so->so_state & SS_HOSTFWD) {
 447             n = snprintf(buf, sizeof(buf), "  UDP[HOST_FORWARD]");
 448             src_len = sizeof(src);
 449             getsockname(so->s, (struct sockaddr *)&src, &src_len);
 450             dst_addr = so->so_laddr;
 451             dst_port = so->so_lport;
 452         } else {
 453             n = snprintf(buf, sizeof(buf), "  UDP[%d sec]",
 454                          (so->so_expire - curtime) / 1000);
 455             src.sin_addr = so->so_laddr;
 456             src.sin_port = so->so_lport;
 457             dst_addr = so->so_faddr;
 458             dst_port = so->so_fport;
 459         }
 460         memset(&buf[n], ' ', 19 - n);
 461         buf[19] = 0;
 462         monitor_printf(mon, "%s %3d %15s %5d ", buf, so->s,
 463                        src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*",
 464                        ntohs(src.sin_port));
 465         monitor_printf(mon, "%15s %5d %5d %5d\n",
 466                        inet_ntoa(dst_addr), ntohs(dst_port),
 467                        so->so_rcv.sb_cc, so->so_snd.sb_cc);
 468     }
 469 }