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 #include "qemu-common.h"
   9 #include <slirp.h>
  10 #include "ip_icmp.h"
  11 #ifdef __sun__
  12 #include <sys/filio.h>
  13 #endif
  14
  15 static void sofcantrcvmore(struct socket *so);
  16 static void sofcantsendmore(struct socket *so);
  17
  18 struct socket *
  19 solookup(struct socket *head, struct in_addr laddr, u_int lport,
  20          struct in_addr faddr, u_int fport)
  21 {
  22         struct socket *so;
  23
  24         for (so = head->so_next; so != head; so = so->so_next) {
  25                 if (so->so_lport == lport &&
  26                     so->so_laddr.s_addr == laddr.s_addr &&
  27                     so->so_faddr.s_addr == faddr.s_addr &&
  28                     so->so_fport == fport)
  29                    break;
  30         }
  31
  32         if (so == head)
  33            return (struct socket *)NULL;
  34         return so;
  35
  36 }
  37
  38 /*
  39  * Create a new socket, initialise the fields
  40  * It is the responsibility of the caller to
  41  * insque() it into the correct linked-list
  42  */
  43 struct socket *
  44 socreate(Slirp *slirp)
  45 {
  46   struct socket *so;
  47
  48   so = (struct socket *)malloc(sizeof(struct socket));
  49   if(so) {
  50     memset(so, 0, sizeof(struct socket));
  51     so->so_state = SS_NOFDREF;
  52     so->s = -1;
  53     so->slirp = slirp;
  54     so->pollfds_idx = -1;
  55   }
  56   return(so);
  57 }
  58
  59 /*
  60  * remque and free a socket, clobber cache
  61  */
  62 void
  63 sofree(struct socket *so)
  64 {
  65   Slirp *slirp = so->slirp;
  66
  67   if (so->so_emu==EMU_RSH && so->extra) {
  68         sofree(so->extra);
  69         so->extra=NULL;
  70   }
  71   if (so == slirp->tcp_last_so) {
  72       slirp->tcp_last_so = &slirp->tcb;
  73   } else if (so == slirp->udp_last_so) {
  74       slirp->udp_last_so = &slirp->udb;
  75   } else if (so == slirp->icmp_last_so) {
  76       slirp->icmp_last_so = &slirp->icmp;
  77   }
  78   m_free(so->so_m);
  79
  80   if(so->so_next && so->so_prev)
  81     remque(so);  /* crashes if so is not in a queue */
  82
  83   free(so);
  84 }
  85
  86 size_t sopreprbuf(struct socket *so, struct iovec *iov, int *np)
  87 {
  88         int n, lss, total;
  89         struct sbuf *sb = &so->so_snd;
  90         int len = sb->sb_datalen - sb->sb_cc;
  91         int mss = so->so_tcpcb->t_maxseg;
  92
  93         DEBUG_CALL("sopreprbuf");
  94         DEBUG_ARG("so = %p", so);
  95
  96         if (len <= 0)
  97                 return 0;
  98
  99         iov[0].iov_base = sb->sb_wptr;
 100         iov[1].iov_base = NULL;
 101         iov[1].iov_len = 0;
 102         if (sb->sb_wptr < sb->sb_rptr) {
 103                 iov[0].iov_len = sb->sb_rptr - sb->sb_wptr;
 104                 /* Should never succeed, but... */
 105                 if (iov[0].iov_len > len)
 106                    iov[0].iov_len = len;
 107                 if (iov[0].iov_len > mss)
 108                    iov[0].iov_len -= iov[0].iov_len%mss;
 109                 n = 1;
 110         } else {
 111                 iov[0].iov_len = (sb->sb_data + sb->sb_datalen) - sb->sb_wptr;
 112                 /* Should never succeed, but... */
 113                 if (iov[0].iov_len > len) iov[0].iov_len = len;
 114                 len -= iov[0].iov_len;
 115                 if (len) {
 116                         iov[1].iov_base = sb->sb_data;
 117                         iov[1].iov_len = sb->sb_rptr - sb->sb_data;
 118                         if(iov[1].iov_len > len)
 119                            iov[1].iov_len = len;
 120                         total = iov[0].iov_len + iov[1].iov_len;
 121                         if (total > mss) {
 122                                 lss = total%mss;
 123                                 if (iov[1].iov_len > lss) {
 124                                         iov[1].iov_len -= lss;
 125                                         n = 2;
 126                                 } else {
 127                                         lss -= iov[1].iov_len;
 128                                         iov[0].iov_len -= lss;
 129                                         n = 1;
 130                                 }
 131                         } else
 132                                 n = 2;
 133                 } else {
 134                         if (iov[0].iov_len > mss)
 135                            iov[0].iov_len -= iov[0].iov_len%mss;
 136                         n = 1;
 137                 }
 138         }
 139         if (np)
 140                 *np = n;
 141
 142         return iov[0].iov_len + (n - 1) * iov[1].iov_len;
 143 }
 144
 145 /*
 146  * Read from so's socket into sb_snd, updating all relevant sbuf fields
 147  * NOTE: This will only be called if it is select()ed for reading, so
 148  * a read() of 0 (or less) means it's disconnected
 149  */
 150 int
 151 soread(struct socket *so)
 152 {
 153         int n, nn;
 154         struct sbuf *sb = &so->so_snd;
 155         struct iovec iov[2];
 156
 157         DEBUG_CALL("soread");
 158         DEBUG_ARG("so = %p", so);
 159
 160         /*
 161          * No need to check if there's enough room to read.
 162          * soread wouldn't have been called if there weren't
 163          */
 164         sopreprbuf(so, iov, &n);
 165
 166 #ifdef HAVE_READV
 167         nn = readv(so->s, (struct iovec *)iov, n);
 168         DEBUG_MISC((dfd, " ... read nn = %d bytes\n", nn));
 169 #else
 170         nn = qemu_recv(so->s, iov[0].iov_base, iov[0].iov_len,0);
 171 #endif
 172         if (nn <= 0) {
 173                 if (nn < 0 && (errno == EINTR || errno == EAGAIN))
 174                         return 0;
 175                 else {
 176                         DEBUG_MISC((dfd, " --- soread() disconnected, nn = %d, errno = %d-%s\n", nn, errno,strerror(errno)));
 177                         sofcantrcvmore(so);
 178                         tcp_sockclosed(sototcpcb(so));
 179                         return -1;
 180                 }
 181         }
 182
 183 #ifndef HAVE_READV
 184         /*
 185          * If there was no error, try and read the second time round
 186          * We read again if n = 2 (ie, there's another part of the buffer)
 187          * and we read as much as we could in the first read
 188          * We don't test for <= 0 this time, because there legitimately
 189          * might not be any more data (since the socket is non-blocking),
 190          * a close will be detected on next iteration.
 191          * A return of -1 wont (shouldn't) happen, since it didn't happen above
 192          */
 193         if (n == 2 && nn == iov[0].iov_len) {
 194             int ret;
 195             ret = qemu_recv(so->s, iov[1].iov_base, iov[1].iov_len,0);
 196             if (ret > 0)
 197                 nn += ret;
 198         }
 199
 200         DEBUG_MISC((dfd, " ... read nn = %d bytes\n", nn));
 201 #endif
 202
 203         /* Update fields */
 204         sb->sb_cc += nn;
 205         sb->sb_wptr += nn;
 206         if (sb->sb_wptr >= (sb->sb_data + sb->sb_datalen))
 207                 sb->sb_wptr -= sb->sb_datalen;
 208         return nn;
 209 }
 210
 211 int soreadbuf(struct socket *so, const char *buf, int size)
 212 {
 213     int n, nn, copy = size;
 214         struct sbuf *sb = &so->so_snd;
 215         struct iovec iov[2];
 216
 217         DEBUG_CALL("soreadbuf");
 218         DEBUG_ARG("so = %p", so);
 219
 220         /*
 221          * No need to check if there's enough room to read.
 222          * soread wouldn't have been called if there weren't
 223          */
 224         if (sopreprbuf(so, iov, &n) < size)
 225         goto err;
 226
 227     nn = MIN(iov[0].iov_len, copy);
 228     memcpy(iov[0].iov_base, buf, nn);
 229
 230     copy -= nn;
 231     buf += nn;
 232
 233     if (copy == 0)
 234         goto done;
 235
 236     memcpy(iov[1].iov_base, buf, copy);
 237
 238 done:
 239     /* Update fields */
 240         sb->sb_cc += size;
 241         sb->sb_wptr += size;
 242         if (sb->sb_wptr >= (sb->sb_data + sb->sb_datalen))
 243                 sb->sb_wptr -= sb->sb_datalen;
 244     return size;
 245 err:
 246
 247     sofcantrcvmore(so);
 248     tcp_sockclosed(sototcpcb(so));
 249     fprintf(stderr, "soreadbuf buffer to small");
 250     return -1;
 251 }
 252
 253 /*
 254  * Get urgent data
 255  *
 256  * When the socket is created, we set it SO_OOBINLINE,
 257  * so when OOB data arrives, we soread() it and everything
 258  * in the send buffer is sent as urgent data
 259  */
 260 void
 261 sorecvoob(struct socket *so)
 262 {
 263         struct tcpcb *tp = sototcpcb(so);
 264
 265         DEBUG_CALL("sorecvoob");
 266         DEBUG_ARG("so = %p", so);
 267
 268         /*
 269          * We take a guess at how much urgent data has arrived.
 270          * In most situations, when urgent data arrives, the next
 271          * read() should get all the urgent data.  This guess will
 272          * be wrong however if more data arrives just after the
 273          * urgent data, or the read() doesn't return all the
 274          * urgent data.
 275          */
 276         soread(so);
 277         tp->snd_up = tp->snd_una + so->so_snd.sb_cc;
 278         tp->t_force = 1;
 279         tcp_output(tp);
 280         tp->t_force = 0;
 281 }
 282
 283 /*
 284  * Send urgent data
 285  * There's a lot duplicated code here, but...
 286  */
 287 int
 288 sosendoob(struct socket *so)
 289 {
 290         struct sbuf *sb = &so->so_rcv;
 291         char buff[2048]; /* XXX Shouldn't be sending more oob data than this */
 292
 293         int n, len;
 294
 295         DEBUG_CALL("sosendoob");
 296         DEBUG_ARG("so = %p", so);
 297         DEBUG_ARG("sb->sb_cc = %d", sb->sb_cc);
 298
 299         if (so->so_urgc > 2048)
 300            so->so_urgc = 2048; /* XXXX */
 301
 302         if (sb->sb_rptr < sb->sb_wptr) {
 303                 /* We can send it directly */
 304                 n = slirp_send(so, sb->sb_rptr, so->so_urgc, (MSG_OOB)); /* |MSG_DONTWAIT)); */
 305                 so->so_urgc -= n;
 306
 307                 DEBUG_MISC((dfd, " --- sent %d bytes urgent data, %d urgent bytes left\n", n, so->so_urgc));
 308         } else {
 309                 /*
 310                  * Since there's no sendv or sendtov like writev,
 311                  * we must copy all data to a linear buffer then
 312                  * send it all
 313                  */
 314                 len = (sb->sb_data + sb->sb_datalen) - sb->sb_rptr;
 315                 if (len > so->so_urgc) len = so->so_urgc;
 316                 memcpy(buff, sb->sb_rptr, len);
 317                 so->so_urgc -= len;
 318                 if (so->so_urgc) {
 319                         n = sb->sb_wptr - sb->sb_data;
 320                         if (n > so->so_urgc) n = so->so_urgc;
 321                         memcpy((buff + len), sb->sb_data, n);
 322                         so->so_urgc -= n;
 323                         len += n;
 324                 }
 325                 n = slirp_send(so, buff, len, (MSG_OOB)); /* |MSG_DONTWAIT)); */
 326 #ifdef DEBUG
 327                 if (n != len)
 328                    DEBUG_ERROR((dfd, "Didn't send all data urgently XXXXX\n"));
 329 #endif
 330                 DEBUG_MISC((dfd, " ---2 sent %d bytes urgent data, %d urgent bytes left\n", n, so->so_urgc));
 331         }
 332
 333         sb->sb_cc -= n;
 334         sb->sb_rptr += n;
 335         if (sb->sb_rptr >= (sb->sb_data + sb->sb_datalen))
 336                 sb->sb_rptr -= sb->sb_datalen;
 337
 338         return n;
 339 }
 340
 341 /*
 342  * Write data from so_rcv to so's socket,
 343  * updating all sbuf field as necessary
 344  */
 345 int
 346 sowrite(struct socket *so)
 347 {
 348         int  n,nn;
 349         struct sbuf *sb = &so->so_rcv;
 350         int len = sb->sb_cc;
 351         struct iovec iov[2];
 352
 353         DEBUG_CALL("sowrite");
 354         DEBUG_ARG("so = %p", so);
 355
 356         if (so->so_urgc) {
 357                 sosendoob(so);
 358                 if (sb->sb_cc == 0)
 359                         return 0;
 360         }
 361
 362         /*
 363          * No need to check if there's something to write,
 364          * sowrite wouldn't have been called otherwise
 365          */
 366
 367         iov[0].iov_base = sb->sb_rptr;
 368         iov[1].iov_base = NULL;
 369         iov[1].iov_len = 0;
 370         if (sb->sb_rptr < sb->sb_wptr) {
 371                 iov[0].iov_len = sb->sb_wptr - sb->sb_rptr;
 372                 /* Should never succeed, but... */
 373                 if (iov[0].iov_len > len) iov[0].iov_len = len;
 374                 n = 1;
 375         } else {
 376                 iov[0].iov_len = (sb->sb_data + sb->sb_datalen) - sb->sb_rptr;
 377                 if (iov[0].iov_len > len) iov[0].iov_len = len;
 378                 len -= iov[0].iov_len;
 379                 if (len) {
 380                         iov[1].iov_base = sb->sb_data;
 381                         iov[1].iov_len = sb->sb_wptr - sb->sb_data;
 382                         if (iov[1].iov_len > len) iov[1].iov_len = len;
 383                         n = 2;
 384                 } else
 385                         n = 1;
 386         }
 387         /* Check if there's urgent data to send, and if so, send it */
 388
 389 #ifdef HAVE_READV
 390         nn = writev(so->s, (const struct iovec *)iov, n);
 391
 392         DEBUG_MISC((dfd, "  ... wrote nn = %d bytes\n", nn));
 393 #else
 394         nn = slirp_send(so, iov[0].iov_base, iov[0].iov_len,0);
 395 #endif
 396         /* This should never happen, but people tell me it does *shrug* */
 397         if (nn < 0 && (errno == EAGAIN || errno == EINTR))
 398                 return 0;
 399
 400         if (nn <= 0) {
 401                 DEBUG_MISC((dfd, " --- sowrite disconnected, so->so_state = %x, errno = %d\n",
 402                         so->so_state, errno));
 403                 sofcantsendmore(so);
 404                 tcp_sockclosed(sototcpcb(so));
 405                 return -1;
 406         }
 407
 408 #ifndef HAVE_READV
 409         if (n == 2 && nn == iov[0].iov_len) {
 410             int ret;
 411             ret = slirp_send(so, iov[1].iov_base, iov[1].iov_len,0);
 412             if (ret > 0)
 413                 nn += ret;
 414         }
 415         DEBUG_MISC((dfd, "  ... wrote nn = %d bytes\n", nn));
 416 #endif
 417
 418         /* Update sbuf */
 419         sb->sb_cc -= nn;
 420         sb->sb_rptr += nn;
 421         if (sb->sb_rptr >= (sb->sb_data + sb->sb_datalen))
 422                 sb->sb_rptr -= sb->sb_datalen;
 423
 424         /*
 425          * If in DRAIN mode, and there's no more data, set
 426          * it CANTSENDMORE
 427          */
 428         if ((so->so_state & SS_FWDRAIN) && sb->sb_cc == 0)
 429                 sofcantsendmore(so);
 430
 431         return nn;
 432 }
 433
 434 /*
 435  * recvfrom() a UDP socket
 436  */
 437 void
 438 sorecvfrom(struct socket *so)
 439 {
 440         struct sockaddr_storage addr;
 441         socklen_t addrlen = sizeof(struct sockaddr_storage);
 442
 443         DEBUG_CALL("sorecvfrom");
 444         DEBUG_ARG("so = %p", so);
 445
 446         if (so->so_type == IPPROTO_ICMP) {   /* This is a "ping" reply */
 447           char buff[256];
 448           int len;
 449
 450           len = recvfrom(so->s, buff, 256, 0,
 451                          (struct sockaddr *)&addr, &addrlen);
 452           /* XXX Check if reply is "correct"? */
 453
 454           if(len == -1 || len == 0) {
 455             u_char code=ICMP_UNREACH_PORT;
 456
 457             if(errno == EHOSTUNREACH) code=ICMP_UNREACH_HOST;
 458             else if(errno == ENETUNREACH) code=ICMP_UNREACH_NET;
 459
 460             DEBUG_MISC((dfd," udp icmp rx errno = %d-%s\n",
 461                         errno,strerror(errno)));
 462             icmp_error(so->so_m, ICMP_UNREACH,code, 0,strerror(errno));
 463           } else {
 464             icmp_reflect(so->so_m);
 465             so->so_m = NULL; /* Don't m_free() it again! */
 466           }
 467           /* No need for this socket anymore, udp_detach it */
 468           udp_detach(so);
 469         } else {                                /* A "normal" UDP packet */
 470           struct mbuf *m;
 471           int len;
 472 #ifdef _WIN32
 473           unsigned long n;
 474 #else
 475           int n;
 476 #endif
 477
 478           m = m_get(so->slirp);
 479           if (!m) {
 480               return;
 481           }
 482           m->m_data += IF_MAXLINKHDR;
 483
 484           /*
 485            * XXX Shouldn't FIONREAD packets destined for port 53,
 486            * but I don't know the max packet size for DNS lookups
 487            */
 488           len = M_FREEROOM(m);
 489           /* if (so->so_fport != htons(53)) { */
 490           ioctlsocket(so->s, FIONREAD, &n);
 491
 492           if (n > len) {
 493             n = (m->m_data - m->m_dat) + m->m_len + n + 1;
 494             m_inc(m, n);
 495             len = M_FREEROOM(m);
 496           }
 497           /* } */
 498
 499           m->m_len = recvfrom(so->s, m->m_data, len, 0,
 500                               (struct sockaddr *)&addr, &addrlen);
 501           DEBUG_MISC((dfd, " did recvfrom %d, errno = %d-%s\n",
 502                       m->m_len, errno,strerror(errno)));
 503           if(m->m_len<0) {
 504             u_char code=ICMP_UNREACH_PORT;
 505
 506             if(errno == EHOSTUNREACH) code=ICMP_UNREACH_HOST;
 507             else if(errno == ENETUNREACH) code=ICMP_UNREACH_NET;
 508
 509             DEBUG_MISC((dfd," rx error, tx icmp ICMP_UNREACH:%i\n", code));
 510             icmp_error(so->so_m, ICMP_UNREACH,code, 0,strerror(errno));
 511             m_free(m);
 512           } else {
 513           /*
 514            * Hack: domain name lookup will be used the most for UDP,
 515            * and since they'll only be used once there's no need
 516            * for the 4 minute (or whatever) timeout... So we time them
 517            * out much quicker (10 seconds  for now...)
 518            */
 519             if (so->so_expire) {
 520               if (so->so_fport == htons(53))
 521                 so->so_expire = curtime + SO_EXPIREFAST;
 522               else
 523                 so->so_expire = curtime + SO_EXPIRE;
 524             }
 525
 526             /*
 527              * If this packet was destined for CTL_ADDR,
 528              * make it look like that's where it came from, done by udp_output
 529              */
 530             switch (so->so_ffamily) {
 531             case AF_INET:
 532                 udp_output(so, m, (struct sockaddr_in *) &addr);
 533                 break;
 534             default:
 535                 break;
 536             }
 537           } /* rx error */
 538         } /* if ping packet */
 539 }
 540
 541 /*
 542  * sendto() a socket
 543  */
 544 int
 545 sosendto(struct socket *so, struct mbuf *m)
 546 {
 547         Slirp *slirp = so->slirp;
 548         int ret;
 549         struct sockaddr_in addr;
 550
 551         DEBUG_CALL("sosendto");
 552         DEBUG_ARG("so = %p", so);
 553         DEBUG_ARG("m = %p", m);
 554
 555         addr.sin_family = AF_INET;
 556         if ((so->so_faddr.s_addr & slirp->vnetwork_mask.s_addr) ==
 557             slirp->vnetwork_addr.s_addr) {
 558           /* It's an alias */
 559           if (so->so_faddr.s_addr == slirp->vnameserver_addr.s_addr) {
 560             if (get_dns_addr(&addr.sin_addr) < 0)
 561               addr.sin_addr = loopback_addr;
 562           } else {
 563             addr.sin_addr = loopback_addr;
 564           }
 565         } else
 566           addr.sin_addr = so->so_faddr;
 567         addr.sin_port = so->so_fport;
 568
 569         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)));
 570
 571         /* Don't care what port we get */
 572         ret = sendto(so->s, m->m_data, m->m_len, 0,
 573                      (struct sockaddr *)&addr, sizeof (struct sockaddr));
 574         if (ret < 0)
 575                 return -1;
 576
 577         /*
 578          * Kill the socket if there's no reply in 4 minutes,
 579          * but only if it's an expirable socket
 580          */
 581         if (so->so_expire)
 582                 so->so_expire = curtime + SO_EXPIRE;
 583         so->so_state &= SS_PERSISTENT_MASK;
 584         so->so_state |= SS_ISFCONNECTED; /* So that it gets select()ed */
 585         return 0;
 586 }
 587
 588 /*
 589  * Listen for incoming TCP connections
 590  */
 591 struct socket *
 592 tcp_listen(Slirp *slirp, uint32_t haddr, u_int hport, uint32_t laddr,
 593            u_int lport, int flags)
 594 {
 595         struct sockaddr_in addr;
 596         struct socket *so;
 597         int s, opt = 1;
 598         socklen_t addrlen = sizeof(addr);
 599         memset(&addr, 0, addrlen);
 600
 601         DEBUG_CALL("tcp_listen");
 602         DEBUG_ARG("haddr = %x", haddr);
 603         DEBUG_ARG("hport = %d", hport);
 604         DEBUG_ARG("laddr = %x", laddr);
 605         DEBUG_ARG("lport = %d", lport);
 606         DEBUG_ARG("flags = %x", flags);
 607
 608         so = socreate(slirp);
 609         if (!so) {
 610           return NULL;
 611         }
 612
 613         /* Don't tcp_attach... we don't need so_snd nor so_rcv */
 614         if ((so->so_tcpcb = tcp_newtcpcb(so)) == NULL) {
 615                 free(so);
 616                 return NULL;
 617         }
 618         insque(so, &slirp->tcb);
 619
 620         /*
 621          * SS_FACCEPTONCE sockets must time out.
 622          */
 623         if (flags & SS_FACCEPTONCE)
 624            so->so_tcpcb->t_timer[TCPT_KEEP] = TCPTV_KEEP_INIT*2;
 625
 626         so->so_state &= SS_PERSISTENT_MASK;
 627         so->so_state |= (SS_FACCEPTCONN | flags);
 628         so->so_lfamily = AF_INET;
 629         so->so_lport = lport; /* Kept in network format */
 630         so->so_laddr.s_addr = laddr; /* Ditto */
 631
 632         addr.sin_family = AF_INET;
 633         addr.sin_addr.s_addr = haddr;
 634         addr.sin_port = hport;
 635
 636         if (((s = qemu_socket(AF_INET,SOCK_STREAM,0)) < 0) ||
 637             (socket_set_fast_reuse(s) < 0) ||
 638             (bind(s,(struct sockaddr *)&addr, sizeof(addr)) < 0) ||
 639             (listen(s,1) < 0)) {
 640                 int tmperrno = errno; /* Don't clobber the real reason we failed */
 641
 642                 close(s);
 643                 sofree(so);
 644                 /* Restore the real errno */
 645 #ifdef _WIN32
 646                 WSASetLastError(tmperrno);
 647 #else
 648                 errno = tmperrno;
 649 #endif
 650                 return NULL;
 651         }
 652         qemu_setsockopt(s, SOL_SOCKET, SO_OOBINLINE, &opt, sizeof(int));
 653
 654         getsockname(s,(struct sockaddr *)&addr,&addrlen);
 655         so->so_ffamily = AF_INET;
 656         so->so_fport = addr.sin_port;
 657         if (addr.sin_addr.s_addr == 0 || addr.sin_addr.s_addr == loopback_addr.s_addr)
 658            so->so_faddr = slirp->vhost_addr;
 659         else
 660            so->so_faddr = addr.sin_addr;
 661
 662         so->s = s;
 663         return so;
 664 }
 665
 666 /*
 667  * Various session state calls
 668  * XXX Should be #define's
 669  * The socket state stuff needs work, these often get call 2 or 3
 670  * times each when only 1 was needed
 671  */
 672 void
 673 soisfconnecting(struct socket *so)
 674 {
 675         so->so_state &= ~(SS_NOFDREF|SS_ISFCONNECTED|SS_FCANTRCVMORE|
 676                           SS_FCANTSENDMORE|SS_FWDRAIN);
 677         so->so_state |= SS_ISFCONNECTING; /* Clobber other states */
 678 }
 679
 680 void
 681 soisfconnected(struct socket *so)
 682 {
 683         so->so_state &= ~(SS_ISFCONNECTING|SS_FWDRAIN|SS_NOFDREF);
 684         so->so_state |= SS_ISFCONNECTED; /* Clobber other states */
 685 }
 686
 687 static void
 688 sofcantrcvmore(struct socket *so)
 689 {
 690         if ((so->so_state & SS_NOFDREF) == 0) {
 691                 shutdown(so->s,0);
 692         }
 693         so->so_state &= ~(SS_ISFCONNECTING);
 694         if (so->so_state & SS_FCANTSENDMORE) {
 695            so->so_state &= SS_PERSISTENT_MASK;
 696            so->so_state |= SS_NOFDREF; /* Don't select it */
 697         } else {
 698            so->so_state |= SS_FCANTRCVMORE;
 699         }
 700 }
 701
 702 static void
 703 sofcantsendmore(struct socket *so)
 704 {
 705         if ((so->so_state & SS_NOFDREF) == 0) {
 706             shutdown(so->s,1);           /* send FIN to fhost */
 707         }
 708         so->so_state &= ~(SS_ISFCONNECTING);
 709         if (so->so_state & SS_FCANTRCVMORE) {
 710            so->so_state &= SS_PERSISTENT_MASK;
 711            so->so_state |= SS_NOFDREF; /* as above */
 712         } else {
 713            so->so_state |= SS_FCANTSENDMORE;
 714         }
 715 }
 716
 717 /*
 718  * Set write drain mode
 719  * Set CANTSENDMORE once all data has been write()n
 720  */
 721 void
 722 sofwdrain(struct socket *so)
 723 {
 724         if (so->so_rcv.sb_cc)
 725                 so->so_state |= SS_FWDRAIN;
 726         else
 727                 sofcantsendmore(so);
 728 }