slirp/socket.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 #define WANT_SYS_IOCTL_H
   9 #include <slirp.h>
  10 #include "ip_icmp.h"
  11 #include "main.h"
  12 #ifdef __sun__
  13 #include <sys/filio.h>
  14 #endif
  15
  16 void
  17 so_init()
  18 {
  19         /* Nothing yet */
  20 }
  21
  22
  23 struct socket *
  24 solookup(head, laddr, lport, faddr, fport)
  25         struct socket *head;
  26         struct in_addr laddr;
  27         u_int lport;
  28         struct in_addr faddr;
  29         u_int fport;
  30 {
  31         struct socket *so;
  32
  33         for (so = head->so_next; so != head; so = so->so_next) {
  34                 if (so->so_lport == lport &&
  35                     so->so_laddr.s_addr == laddr.s_addr &&
  36                     so->so_faddr.s_addr == faddr.s_addr &&
  37                     so->so_fport == fport)
  38                    break;
  39         }
  40
  41         if (so == head)
  42            return (struct socket *)NULL;
  43         return so;
  44
  45 }
  46
  47 /*
  48  * Create a new socket, initialise the fields
  49  * It is the responsibility of the caller to
  50  * insque() it into the correct linked-list
  51  */
  52 struct socket *
  53 socreate()
  54 {
  55   struct socket *so;
  56
  57   so = (struct socket *)malloc(sizeof(struct socket));
  58   if(so) {
  59     memset(so, 0, sizeof(struct socket));
  60     so->so_state = SS_NOFDREF;
  61     so->s = -1;
  62   }
  63   return(so);
  64 }
  65
  66 /*
  67  * remque and free a socket, clobber cache
  68  */
  69 void
  70 sofree(so)
  71         struct socket *so;
  72 {
  73   if (so->so_emu==EMU_RSH && so->extra) {
  74         sofree(so->extra);
  75         so->extra=NULL;
  76   }
  77   if (so == tcp_last_so)
  78     tcp_last_so = &tcb;
  79   else if (so == udp_last_so)
  80     udp_last_so = &udb;
  81
  82   m_free(so->so_m);
  83
  84   if(so->so_next && so->so_prev)
  85     remque(so);  /* crashes if so is not in a queue */
  86
  87   free(so);
  88 }
  89
  90 /*
  91  * Read from so's socket into sb_snd, updating all relevant sbuf fields
  92  * NOTE: This will only be called if it is select()ed for reading, so
  93  * a read() of 0 (or less) means it's disconnected
  94  */
  95 int
  96 soread(so)
  97         struct socket *so;
  98 {
  99         int n, nn, lss, total;
 100         struct sbuf *sb = &so->so_snd;
 101         int len = sb->sb_datalen - sb->sb_cc;
 102         struct iovec iov[2];
 103         int mss = so->so_tcpcb->t_maxseg;
 104
 105         DEBUG_CALL("soread");
 106         DEBUG_ARG("so = %lx", (long )so);
 107
 108         /*
 109          * No need to check if there's enough room to read.
 110          * soread wouldn't have been called if there weren't
 111          */
 112
 113         len = sb->sb_datalen - sb->sb_cc;
 114
 115         iov[0].iov_base = sb->sb_wptr;
 116         if (sb->sb_wptr < sb->sb_rptr) {
 117                 iov[0].iov_len = sb->sb_rptr - sb->sb_wptr;
 118                 /* Should never succeed, but... */
 119                 if (iov[0].iov_len > len)
 120                    iov[0].iov_len = len;
 121                 if (iov[0].iov_len > mss)
 122                    iov[0].iov_len -= iov[0].iov_len%mss;
 123                 n = 1;
 124         } else {
 125                 iov[0].iov_len = (sb->sb_data + sb->sb_datalen) - sb->sb_wptr;
 126                 /* Should never succeed, but... */
 127                 if (iov[0].iov_len > len) iov[0].iov_len = len;
 128                 len -= iov[0].iov_len;
 129                 if (len) {
 130                         iov[1].iov_base = sb->sb_data;
 131                         iov[1].iov_len = sb->sb_rptr - sb->sb_data;
 132                         if(iov[1].iov_len > len)
 133                            iov[1].iov_len = len;
 134                         total = iov[0].iov_len + iov[1].iov_len;
 135                         if (total > mss) {
 136                                 lss = total%mss;
 137                                 if (iov[1].iov_len > lss) {
 138                                         iov[1].iov_len -= lss;
 139                                         n = 2;
 140                                 } else {
 141                                         lss -= iov[1].iov_len;
 142                                         iov[0].iov_len -= lss;
 143                                         n = 1;
 144                                 }
 145                         } else
 146                                 n = 2;
 147                 } else {
 148                         if (iov[0].iov_len > mss)
 149                            iov[0].iov_len -= iov[0].iov_len%mss;
 150                         n = 1;
 151                 }
 152         }
 153
 154 #ifdef HAVE_READV
 155         nn = readv(so->s, (struct iovec *)iov, n);
 156         DEBUG_MISC((dfd, " ... read nn = %d bytes\n", nn));
 157 #else
 158         nn = recv(so->s, iov[0].iov_base, iov[0].iov_len,0);
 159 #endif
 160         if (nn <= 0) {
 161                 if (nn < 0 && (errno == EINTR || errno == EAGAIN))
 162                         return 0;
 163                 else {
 164                         DEBUG_MISC((dfd, " --- soread() disconnected, nn = %d, errno = %d-%s\n", nn, errno,strerror(errno)));
 165                         sofcantrcvmore(so);
 166                         tcp_sockclosed(sototcpcb(so));
 167                         return -1;
 168                 }
 169         }
 170
 171 #ifndef HAVE_READV
 172         /*
 173          * If there was no error, try and read the second time round
 174          * We read again if n = 2 (ie, there's another part of the buffer)
 175          * and we read as much as we could in the first read
 176          * We don't test for <= 0 this time, because there legitimately
 177          * might not be any more data (since the socket is non-blocking),
 178          * a close will be detected on next iteration.
 179          * A return of -1 wont (shouldn't) happen, since it didn't happen above
 180          */
 181         if (n == 2 && nn == iov[0].iov_len) {
 182             int ret;
 183             ret = recv(so->s, iov[1].iov_base, iov[1].iov_len,0);
 184             if (ret > 0)
 185                 nn += ret;
 186         }
 187
 188         DEBUG_MISC((dfd, " ... read nn = %d bytes\n", nn));
 189 #endif
 190
 191         /* Update fields */
 192         sb->sb_cc += nn;
 193         sb->sb_wptr += nn;
 194         if (sb->sb_wptr >= (sb->sb_data + sb->sb_datalen))
 195                 sb->sb_wptr -= sb->sb_datalen;
 196         return nn;
 197 }
 198
 199 /*
 200  * Get urgent data
 201  *
 202  * When the socket is created, we set it SO_OOBINLINE,
 203  * so when OOB data arrives, we soread() it and everything
 204  * in the send buffer is sent as urgent data
 205  */
 206 void
 207 sorecvoob(so)
 208         struct socket *so;
 209 {
 210         struct tcpcb *tp = sototcpcb(so);
 211
 212         DEBUG_CALL("sorecvoob");
 213         DEBUG_ARG("so = %lx", (long)so);
 214
 215         /*
 216          * We take a guess at how much urgent data has arrived.
 217          * In most situations, when urgent data arrives, the next
 218          * read() should get all the urgent data.  This guess will
 219          * be wrong however if more data arrives just after the
 220          * urgent data, or the read() doesn't return all the
 221          * urgent data.
 222          */
 223         soread(so);
 224         tp->snd_up = tp->snd_una + so->so_snd.sb_cc;
 225         tp->t_force = 1;
 226         tcp_output(tp);
 227         tp->t_force = 0;
 228 }
 229
 230 /*
 231  * Send urgent data
 232  * There's a lot duplicated code here, but...
 233  */
 234 int
 235 sosendoob(so)
 236         struct socket *so;
 237 {
 238         struct sbuf *sb = &so->so_rcv;
 239         char buff[2048]; /* XXX Shouldn't be sending more oob data than this */
 240
 241         int n, len;
 242
 243         DEBUG_CALL("sosendoob");
 244         DEBUG_ARG("so = %lx", (long)so);
 245         DEBUG_ARG("sb->sb_cc = %d", sb->sb_cc);
 246
 247         if (so->so_urgc > 2048)
 248            so->so_urgc = 2048; /* XXXX */
 249
 250         if (sb->sb_rptr < sb->sb_wptr) {
 251                 /* We can send it directly */
 252                 n = send(so->s, sb->sb_rptr, so->so_urgc, (MSG_OOB)); /* |MSG_DONTWAIT)); */
 253                 so->so_urgc -= n;
 254
 255                 DEBUG_MISC((dfd, " --- sent %d bytes urgent data, %d urgent bytes left\n", n, so->so_urgc));
 256         } else {
 257                 /*
 258                  * Since there's no sendv or sendtov like writev,
 259                  * we must copy all data to a linear buffer then
 260                  * send it all
 261                  */
 262                 len = (sb->sb_data + sb->sb_datalen) - sb->sb_rptr;
 263                 if (len > so->so_urgc) len = so->so_urgc;
 264                 memcpy(buff, sb->sb_rptr, len);
 265                 so->so_urgc -= len;
 266                 if (so->so_urgc) {
 267                         n = sb->sb_wptr - sb->sb_data;
 268                         if (n > so->so_urgc) n = so->so_urgc;
 269                         memcpy((buff + len), sb->sb_data, n);
 270                         so->so_urgc -= n;
 271                         len += n;
 272                 }
 273                 n = send(so->s, buff, len, (MSG_OOB)); /* |MSG_DONTWAIT)); */
 274 #ifdef DEBUG
 275                 if (n != len)
 276                    DEBUG_ERROR((dfd, "Didn't send all data urgently XXXXX\n"));
 277 #endif
 278                 DEBUG_MISC((dfd, " ---2 sent %d bytes urgent data, %d urgent bytes left\n", n, so->so_urgc));
 279         }
 280
 281         sb->sb_cc -= n;
 282         sb->sb_rptr += n;
 283         if (sb->sb_rptr >= (sb->sb_data + sb->sb_datalen))
 284                 sb->sb_rptr -= sb->sb_datalen;
 285
 286         return n;
 287 }
 288
 289 /*
 290  * Write data from so_rcv to so's socket,
 291  * updating all sbuf field as necessary
 292  */
 293 int
 294 sowrite(so)
 295         struct socket *so;
 296 {
 297         int  n,nn;
 298         struct sbuf *sb = &so->so_rcv;
 299         int len = sb->sb_cc;
 300         struct iovec iov[2];
 301
 302         DEBUG_CALL("sowrite");
 303         DEBUG_ARG("so = %lx", (long)so);
 304
 305         if (so->so_urgc) {
 306                 sosendoob(so);
 307                 if (sb->sb_cc == 0)
 308                         return 0;
 309         }
 310
 311         /*
 312          * No need to check if there's something to write,
 313          * sowrite wouldn't have been called otherwise
 314          */
 315
 316         len = sb->sb_cc;
 317
 318         iov[0].iov_base = sb->sb_rptr;
 319         if (sb->sb_rptr < sb->sb_wptr) {
 320                 iov[0].iov_len = sb->sb_wptr - sb->sb_rptr;
 321                 /* Should never succeed, but... */
 322                 if (iov[0].iov_len > len) iov[0].iov_len = len;
 323                 n = 1;
 324         } else {
 325                 iov[0].iov_len = (sb->sb_data + sb->sb_datalen) - sb->sb_rptr;
 326                 if (iov[0].iov_len > len) iov[0].iov_len = len;
 327                 len -= iov[0].iov_len;
 328                 if (len) {
 329                         iov[1].iov_base = sb->sb_data;
 330                         iov[1].iov_len = sb->sb_wptr - sb->sb_data;
 331                         if (iov[1].iov_len > len) iov[1].iov_len = len;
 332                         n = 2;
 333                 } else
 334                         n = 1;
 335         }
 336         /* Check if there's urgent data to send, and if so, send it */
 337
 338 #ifdef HAVE_READV
 339         nn = writev(so->s, (const struct iovec *)iov, n);
 340
 341         DEBUG_MISC((dfd, "  ... wrote nn = %d bytes\n", nn));
 342 #else
 343         nn = send(so->s, iov[0].iov_base, iov[0].iov_len,0);
 344 #endif
 345         /* This should never happen, but people tell me it does *shrug* */
 346         if (nn < 0 && (errno == EAGAIN || errno == EINTR))
 347                 return 0;
 348
 349         if (nn <= 0) {
 350                 DEBUG_MISC((dfd, " --- sowrite disconnected, so->so_state = %x, errno = %d\n",
 351                         so->so_state, errno));
 352                 sofcantsendmore(so);
 353                 tcp_sockclosed(sototcpcb(so));
 354                 return -1;
 355         }
 356
 357 #ifndef HAVE_READV
 358         if (n == 2 && nn == iov[0].iov_len) {
 359             int ret;
 360             ret = send(so->s, iov[1].iov_base, iov[1].iov_len,0);
 361             if (ret > 0)
 362                 nn += ret;
 363         }
 364         DEBUG_MISC((dfd, "  ... wrote nn = %d bytes\n", nn));
 365 #endif
 366
 367         /* Update sbuf */
 368         sb->sb_cc -= nn;
 369         sb->sb_rptr += nn;
 370         if (sb->sb_rptr >= (sb->sb_data + sb->sb_datalen))
 371                 sb->sb_rptr -= sb->sb_datalen;
 372
 373         /*
 374          * If in DRAIN mode, and there's no more data, set
 375          * it CANTSENDMORE
 376          */
 377         if ((so->so_state & SS_FWDRAIN) && sb->sb_cc == 0)
 378                 sofcantsendmore(so);
 379
 380         return nn;
 381 }
 382
 383 /*
 384  * recvfrom() a UDP socket
 385  */
 386 void
 387 sorecvfrom(so)
 388         struct socket *so;
 389 {
 390         struct sockaddr_in addr;
 391         int addrlen = sizeof(struct sockaddr_in);
 392
 393         DEBUG_CALL("sorecvfrom");
 394         DEBUG_ARG("so = %lx", (long)so);
 395
 396         if (so->so_type == IPPROTO_ICMP) {   /* This is a "ping" reply */
 397           char buff[256];
 398           int len;
 399
 400           len = recvfrom(so->s, buff, 256, 0,
 401                          (struct sockaddr *)&addr, &addrlen);
 402           /* XXX Check if reply is "correct"? */
 403
 404           if(len == -1 || len == 0) {
 405             u_char code=ICMP_UNREACH_PORT;
 406
 407             if(errno == EHOSTUNREACH) code=ICMP_UNREACH_HOST;
 408             else if(errno == ENETUNREACH) code=ICMP_UNREACH_NET;
 409
 410             DEBUG_MISC((dfd," udp icmp rx errno = %d-%s\n",
 411                         errno,strerror(errno)));
 412             icmp_error(so->so_m, ICMP_UNREACH,code, 0,strerror(errno));
 413           } else {
 414             icmp_reflect(so->so_m);
 415             so->so_m = 0; /* Don't m_free() it again! */
 416           }
 417           /* No need for this socket anymore, udp_detach it */
 418           udp_detach(so);
 419         } else {                                /* A "normal" UDP packet */
 420           struct mbuf *m;
 421           int len, n;
 422
 423           if (!(m = m_get())) return;
 424           m->m_data += if_maxlinkhdr;
 425
 426           /*
 427            * XXX Shouldn't FIONREAD packets destined for port 53,
 428            * but I don't know the max packet size for DNS lookups
 429            */
 430           len = M_FREEROOM(m);
 431           /* if (so->so_fport != htons(53)) { */
 432           ioctlsocket(so->s, FIONREAD, &n);
 433
 434           if (n > len) {
 435             n = (m->m_data - m->m_dat) + m->m_len + n + 1;
 436             m_inc(m, n);
 437             len = M_FREEROOM(m);
 438           }
 439           /* } */
 440
 441           m->m_len = recvfrom(so->s, m->m_data, len, 0,
 442                               (struct sockaddr *)&addr, &addrlen);
 443           DEBUG_MISC((dfd, " did recvfrom %d, errno = %d-%s\n",
 444                       m->m_len, errno,strerror(errno)));
 445           if(m->m_len<0) {
 446             u_char code=ICMP_UNREACH_PORT;
 447
 448             if(errno == EHOSTUNREACH) code=ICMP_UNREACH_HOST;
 449             else if(errno == ENETUNREACH) code=ICMP_UNREACH_NET;
 450
 451             DEBUG_MISC((dfd," rx error, tx icmp ICMP_UNREACH:%i\n", code));
 452             icmp_error(so->so_m, ICMP_UNREACH,code, 0,strerror(errno));
 453             m_free(m);
 454           } else {
 455           /*
 456            * Hack: domain name lookup will be used the most for UDP,
 457            * and since they'll only be used once there's no need
 458            * for the 4 minute (or whatever) timeout... So we time them
 459            * out much quicker (10 seconds  for now...)
 460            */
 461             if (so->so_expire) {
 462               if (so->so_fport == htons(53))
 463                 so->so_expire = curtime + SO_EXPIREFAST;
 464               else
 465                 so->so_expire = curtime + SO_EXPIRE;
 466             }
 467
 468             /*          if (m->m_len == len) {
 469              *                  m_inc(m, MINCSIZE);
 470              *                  m->m_len = 0;
 471              *          }
 472              */
 473
 474             /*
 475              * If this packet was destined for CTL_ADDR,
 476              * make it look like that's where it came from, done by udp_output
 477              */
 478             udp_output(so, m, &addr);
 479           } /* rx error */
 480         } /* if ping packet */
 481 }
 482
 483 /*
 484  * sendto() a socket
 485  */
 486 int
 487 sosendto(so, m)
 488         struct socket *so;
 489         struct mbuf *m;
 490 {
 491         int ret;
 492         struct sockaddr_in addr;
 493
 494         DEBUG_CALL("sosendto");
 495         DEBUG_ARG("so = %lx", (long)so);
 496         DEBUG_ARG("m = %lx", (long)m);
 497
 498         addr.sin_family = AF_INET;
 499         if ((so->so_faddr.s_addr & htonl(0xffffff00)) == special_addr.s_addr) {
 500           /* It's an alias */
 501           switch(ntohl(so->so_faddr.s_addr) & 0xff) {
 502           case CTL_DNS:
 503             addr.sin_addr = dns_addr;
 504             break;
 505           case CTL_ALIAS:
 506           default:
 507             addr.sin_addr = loopback_addr;
 508             break;
 509           }
 510         } else
 511           addr.sin_addr = so->so_faddr;
 512         addr.sin_port = so->so_fport;
 513
 514         DEBUG_MISC((dfd, " sendto()ing, addr.sin_port=%d, addr.sin_addr.s_addr=%.16s\n", ntohs(addr.sin_port), inet_ntoa(addr.sin_addr)));
 515
 516         /* Don't care what port we get */
 517         ret = sendto(so->s, m->m_data, m->m_len, 0,
 518                      (struct sockaddr *)&addr, sizeof (struct sockaddr));
 519         if (ret < 0)
 520                 return -1;
 521
 522         /*
 523          * Kill the socket if there's no reply in 4 minutes,
 524          * but only if it's an expirable socket
 525          */
 526         if (so->so_expire)
 527                 so->so_expire = curtime + SO_EXPIRE;
 528         so->so_state = SS_ISFCONNECTED; /* So that it gets select()ed */
 529         return 0;
 530 }
 531
 532 /*
 533  * XXX This should really be tcp_listen
 534  */
 535 struct socket *
 536 solisten(port, laddr, lport, flags)
 537         u_int port;
 538         u_int32_t laddr;
 539         u_int lport;
 540         int flags;
 541 {
 542         struct sockaddr_in addr;
 543         struct socket *so;
 544         int s, addrlen = sizeof(addr), opt = 1;
 545
 546         DEBUG_CALL("solisten");
 547         DEBUG_ARG("port = %d", port);
 548         DEBUG_ARG("laddr = %x", laddr);
 549         DEBUG_ARG("lport = %d", lport);
 550         DEBUG_ARG("flags = %x", flags);
 551
 552         if ((so = socreate()) == NULL) {
 553           /* free(so);      Not sofree() ??? free(NULL) == NOP */
 554           return NULL;
 555         }
 556
 557         /* Don't tcp_attach... we don't need so_snd nor so_rcv */
 558         if ((so->so_tcpcb = tcp_newtcpcb(so)) == NULL) {
 559                 free(so);
 560                 return NULL;
 561         }
 562         insque(so,&tcb);
 563
 564         /*
 565          * SS_FACCEPTONCE sockets must time out.
 566          */
 567         if (flags & SS_FACCEPTONCE)
 568            so->so_tcpcb->t_timer[TCPT_KEEP] = TCPTV_KEEP_INIT*2;
 569
 570         so->so_state = (SS_FACCEPTCONN|flags);
 571         so->so_lport = lport; /* Kept in network format */
 572         so->so_laddr.s_addr = laddr; /* Ditto */
 573
 574         addr.sin_family = AF_INET;
 575         addr.sin_addr.s_addr = INADDR_ANY;
 576         addr.sin_port = port;
 577
 578         if (((s = socket(AF_INET,SOCK_STREAM,0)) < 0) ||
 579             (setsockopt(s,SOL_SOCKET,SO_REUSEADDR,(char *)&opt,sizeof(int)) < 0) ||
 580             (bind(s,(struct sockaddr *)&addr, sizeof(addr)) < 0) ||
 581             (listen(s,1) < 0)) {
 582                 int tmperrno = errno; /* Don't clobber the real reason we failed */
 583
 584                 close(s);
 585                 sofree(so);
 586                 /* Restore the real errno */
 587 #ifdef _WIN32
 588                 WSASetLastError(tmperrno);
 589 #else
 590                 errno = tmperrno;
 591 #endif
 592                 return NULL;
 593         }
 594         setsockopt(s,SOL_SOCKET,SO_OOBINLINE,(char *)&opt,sizeof(int));
 595
 596         getsockname(s,(struct sockaddr *)&addr,&addrlen);
 597         so->so_fport = addr.sin_port;
 598         if (addr.sin_addr.s_addr == 0 || addr.sin_addr.s_addr == loopback_addr.s_addr)
 599            so->so_faddr = alias_addr;
 600         else
 601            so->so_faddr = addr.sin_addr;
 602
 603         so->s = s;
 604         return so;
 605 }
 606
 607 /*
 608  * Data is available in so_rcv
 609  * Just write() the data to the socket
 610  * XXX not yet...
 611  */
 612 void
 613 sorwakeup(so)
 614         struct socket *so;
 615 {
 616 /*      sowrite(so); */
 617 /*      FD_CLR(so->s,&writefds); */
 618 }
 619
 620 /*
 621  * Data has been freed in so_snd
 622  * We have room for a read() if we want to
 623  * For now, don't read, it'll be done in the main loop
 624  */
 625 void
 626 sowwakeup(so)
 627         struct socket *so;
 628 {
 629         /* Nothing, yet */
 630 }
 631
 632 /*
 633  * Various session state calls
 634  * XXX Should be #define's
 635  * The socket state stuff needs work, these often get call 2 or 3
 636  * times each when only 1 was needed
 637  */
 638 void
 639 soisfconnecting(so)
 640         register struct socket *so;
 641 {
 642         so->so_state &= ~(SS_NOFDREF|SS_ISFCONNECTED|SS_FCANTRCVMORE|
 643                           SS_FCANTSENDMORE|SS_FWDRAIN);
 644         so->so_state |= SS_ISFCONNECTING; /* Clobber other states */
 645 }
 646
 647 void
 648 soisfconnected(so)
 649         register struct socket *so;
 650 {
 651         so->so_state &= ~(SS_ISFCONNECTING|SS_FWDRAIN|SS_NOFDREF);
 652         so->so_state |= SS_ISFCONNECTED; /* Clobber other states */
 653 }
 654
 655 void
 656 sofcantrcvmore(so)
 657         struct  socket *so;
 658 {
 659         if ((so->so_state & SS_NOFDREF) == 0) {
 660                 shutdown(so->s,0);
 661                 if(global_writefds) {
 662                   FD_CLR(so->s,global_writefds);
 663                 }
 664         }
 665         so->so_state &= ~(SS_ISFCONNECTING);
 666         if (so->so_state & SS_FCANTSENDMORE)
 667            so->so_state = SS_NOFDREF; /* Don't select it */ /* XXX close() here as well? */
 668         else
 669            so->so_state |= SS_FCANTRCVMORE;
 670 }
 671
 672 void
 673 sofcantsendmore(so)
 674         struct socket *so;
 675 {
 676         if ((so->so_state & SS_NOFDREF) == 0) {
 677             shutdown(so->s,1);           /* send FIN to fhost */
 678             if (global_readfds) {
 679                 FD_CLR(so->s,global_readfds);
 680             }
 681             if (global_xfds) {
 682                 FD_CLR(so->s,global_xfds);
 683             }
 684         }
 685         so->so_state &= ~(SS_ISFCONNECTING);
 686         if (so->so_state & SS_FCANTRCVMORE)
 687            so->so_state = SS_NOFDREF; /* as above */
 688         else
 689            so->so_state |= SS_FCANTSENDMORE;
 690 }
 691
 692 void
 693 soisfdisconnected(so)
 694         struct socket *so;
 695 {
 696 /*      so->so_state &= ~(SS_ISFCONNECTING|SS_ISFCONNECTED); */
 697 /*      close(so->s); */
 698 /*      so->so_state = SS_ISFDISCONNECTED; */
 699         /*
 700          * XXX Do nothing ... ?
 701          */
 702 }
 703
 704 /*
 705  * Set write drain mode
 706  * Set CANTSENDMORE once all data has been write()n
 707  */
 708 void
 709 sofwdrain(so)
 710         struct socket *so;
 711 {
 712         if (so->so_rcv.sb_cc)
 713                 so->so_state |= SS_FWDRAIN;
 714         else
 715                 sofcantsendmore(so);
 716 }
 717