slirp/src/socket.c

   1 /* SPDX-License-Identifier: BSD-3-Clause */
   2 /*
   3  * Copyright (c) 1995 Danny Gasparovski.
   4  */
   5
   6 #include "slirp.h"
   7 #include "ip_icmp.h"
   8 #ifdef __sun__
   9 #include <sys/filio.h>
  10 #endif
  11
  12 static void sofcantrcvmore(struct socket *so);
  13 static void sofcantsendmore(struct socket *so);
  14
  15 struct socket *solookup(struct socket **last, struct socket *head,
  16         struct sockaddr_storage *lhost, struct sockaddr_storage *fhost)
  17 {
  18     struct socket *so = *last;
  19
  20     /* Optimisation */
  21     if (so != head && sockaddr_equal(&(so->lhost.ss), lhost)
  22             && (!fhost || sockaddr_equal(&so->fhost.ss, fhost))) {
  23         return so;
  24     }
  25
  26     for (so = head->so_next; so != head; so = so->so_next) {
  27         if (sockaddr_equal(&(so->lhost.ss), lhost)
  28                 && (!fhost || sockaddr_equal(&so->fhost.ss, fhost))) {
  29             *last = so;
  30             return so;
  31         }
  32     }
  33
  34     return (struct socket *)NULL;
  35 }
  36
  37 /*
  38  * Create a new socket, initialise the fields
  39  * It is the responsibility of the caller to
  40  * insque() it into the correct linked-list
  41  */
  42 struct socket *
  43 socreate(Slirp *slirp)
  44 {
  45     struct socket *so = g_new(struct socket, 1);
  46
  47     memset(so, 0, sizeof(struct socket));
  48     so->so_state = SS_NOFDREF;
  49     so->s = -1;
  50     so->slirp = slirp;
  51     so->pollfds_idx = -1;
  52
  53     return so;
  54 }
  55
  56 /*
  57  * Remove references to so from the given message queue.
  58  */
  59 static void
  60 soqfree(struct socket *so, struct quehead *qh)
  61 {
  62     struct mbuf *ifq;
  63
  64     for (ifq = (struct mbuf *) qh->qh_link;
  65              (struct quehead *) ifq != qh;
  66              ifq = ifq->ifq_next) {
  67         if (ifq->ifq_so == so) {
  68             struct mbuf *ifm;
  69             ifq->ifq_so = NULL;
  70             for (ifm = ifq->ifs_next; ifm != ifq; ifm = ifm->ifs_next) {
  71                 ifm->ifq_so = NULL;
  72             }
  73         }
  74     }
  75 }
  76
  77 /*
  78  * remque and free a socket, clobber cache
  79  */
  80 void
  81 sofree(struct socket *so)
  82 {
  83   Slirp *slirp = so->slirp;
  84
  85   soqfree(so, &slirp->if_fastq);
  86   soqfree(so, &slirp->if_batchq);
  87
  88   if (so == slirp->tcp_last_so) {
  89       slirp->tcp_last_so = &slirp->tcb;
  90   } else if (so == slirp->udp_last_so) {
  91       slirp->udp_last_so = &slirp->udb;
  92   } else if (so == slirp->icmp_last_so) {
  93       slirp->icmp_last_so = &slirp->icmp;
  94   }
  95   m_free(so->so_m);
  96
  97   if(so->so_next && so->so_prev)
  98     remque(so);  /* crashes if so is not in a queue */
  99
 100   if (so->so_tcpcb) {
 101       free(so->so_tcpcb);
 102   }
 103   g_free(so);
 104 }
 105
 106 size_t sopreprbuf(struct socket *so, struct iovec *iov, int *np)
 107 {
 108         int n, lss, total;
 109         struct sbuf *sb = &so->so_snd;
 110         int len = sb->sb_datalen - sb->sb_cc;
 111         int mss = so->so_tcpcb->t_maxseg;
 112
 113         DEBUG_CALL("sopreprbuf");
 114         DEBUG_ARG("so = %p", so);
 115
 116         if (len <= 0)
 117                 return 0;
 118
 119         iov[0].iov_base = sb->sb_wptr;
 120         iov[1].iov_base = NULL;
 121         iov[1].iov_len = 0;
 122         if (sb->sb_wptr < sb->sb_rptr) {
 123                 iov[0].iov_len = sb->sb_rptr - sb->sb_wptr;
 124                 /* Should never succeed, but... */
 125                 if (iov[0].iov_len > len)
 126                    iov[0].iov_len = len;
 127                 if (iov[0].iov_len > mss)
 128                    iov[0].iov_len -= iov[0].iov_len%mss;
 129                 n = 1;
 130         } else {
 131                 iov[0].iov_len = (sb->sb_data + sb->sb_datalen) - sb->sb_wptr;
 132                 /* Should never succeed, but... */
 133                 if (iov[0].iov_len > len) iov[0].iov_len = len;
 134                 len -= iov[0].iov_len;
 135                 if (len) {
 136                         iov[1].iov_base = sb->sb_data;
 137                         iov[1].iov_len = sb->sb_rptr - sb->sb_data;
 138                         if(iov[1].iov_len > len)
 139                            iov[1].iov_len = len;
 140                         total = iov[0].iov_len + iov[1].iov_len;
 141                         if (total > mss) {
 142                                 lss = total%mss;
 143                                 if (iov[1].iov_len > lss) {
 144                                         iov[1].iov_len -= lss;
 145                                         n = 2;
 146                                 } else {
 147                                         lss -= iov[1].iov_len;
 148                                         iov[0].iov_len -= lss;
 149                                         n = 1;
 150                                 }
 151                         } else
 152                                 n = 2;
 153                 } else {
 154                         if (iov[0].iov_len > mss)
 155                            iov[0].iov_len -= iov[0].iov_len%mss;
 156                         n = 1;
 157                 }
 158         }
 159         if (np)
 160                 *np = n;
 161
 162         return iov[0].iov_len + (n - 1) * iov[1].iov_len;
 163 }
 164
 165 /*
 166  * Read from so's socket into sb_snd, updating all relevant sbuf fields
 167  * NOTE: This will only be called if it is select()ed for reading, so
 168  * a read() of 0 (or less) means it's disconnected
 169  */
 170 int
 171 soread(struct socket *so)
 172 {
 173         int n, nn;
 174         size_t buf_len;
 175         struct sbuf *sb = &so->so_snd;
 176         struct iovec iov[2];
 177
 178         DEBUG_CALL("soread");
 179         DEBUG_ARG("so = %p", so);
 180
 181         /*
 182          * No need to check if there's enough room to read.
 183          * soread wouldn't have been called if there weren't
 184          */
 185         buf_len = sopreprbuf(so, iov, &n);
 186         assert(buf_len != 0);
 187
 188         nn = recv(so->s, iov[0].iov_base, iov[0].iov_len,0);
 189         if (nn <= 0) {
 190                 if (nn < 0 && (errno == EINTR || errno == EAGAIN))
 191                         return 0;
 192                 else {
 193                         int err;
 194                         socklen_t elen = sizeof err;
 195                         struct sockaddr_storage addr;
 196                         struct sockaddr *paddr = (struct sockaddr *) &addr;
 197                         socklen_t alen = sizeof addr;
 198
 199                         err = errno;
 200                         if (nn == 0) {
 201                                 if (getpeername(so->s, paddr, &alen) < 0) {
 202                                         err = errno;
 203                                 } else {
 204                                         getsockopt(so->s, SOL_SOCKET, SO_ERROR,
 205                                                 &err, &elen);
 206                                 }
 207                         }
 208
 209                         DEBUG_MISC(" --- soread() disconnected, nn = %d, errno = %d-%s",
 210                        nn, errno,strerror(errno));
 211                         sofcantrcvmore(so);
 212
 213                         if (err == ECONNRESET || err == ECONNREFUSED
 214                             || err == ENOTCONN || err == EPIPE) {
 215                                 tcp_drop(sototcpcb(so), err);
 216                         } else {
 217                                 tcp_sockclosed(sototcpcb(so));
 218                         }
 219                         return -1;
 220                 }
 221         }
 222
 223         /*
 224          * If there was no error, try and read the second time round
 225          * We read again if n = 2 (ie, there's another part of the buffer)
 226          * and we read as much as we could in the first read
 227          * We don't test for <= 0 this time, because there legitimately
 228          * might not be any more data (since the socket is non-blocking),
 229          * a close will be detected on next iteration.
 230          * A return of -1 won't (shouldn't) happen, since it didn't happen above
 231          */
 232         if (n == 2 && nn == iov[0].iov_len) {
 233             int ret;
 234             ret = recv(so->s, iov[1].iov_base, iov[1].iov_len,0);
 235             if (ret > 0)
 236                 nn += ret;
 237         }
 238
 239         DEBUG_MISC(" ... read nn = %d bytes", nn);
 240
 241         /* Update fields */
 242         sb->sb_cc += nn;
 243         sb->sb_wptr += nn;
 244         if (sb->sb_wptr >= (sb->sb_data + sb->sb_datalen))
 245                 sb->sb_wptr -= sb->sb_datalen;
 246         return nn;
 247 }
 248
 249 int soreadbuf(struct socket *so, const char *buf, int size)
 250 {
 251     int n, nn, copy = size;
 252         struct sbuf *sb = &so->so_snd;
 253         struct iovec iov[2];
 254
 255         DEBUG_CALL("soreadbuf");
 256         DEBUG_ARG("so = %p", so);
 257
 258         /*
 259          * No need to check if there's enough room to read.
 260          * soread wouldn't have been called if there weren't
 261          */
 262         assert(size > 0);
 263         if (sopreprbuf(so, iov, &n) < size)
 264         goto err;
 265
 266     nn = MIN(iov[0].iov_len, copy);
 267     memcpy(iov[0].iov_base, buf, nn);
 268
 269     copy -= nn;
 270     buf += nn;
 271
 272     if (copy == 0)
 273         goto done;
 274
 275     memcpy(iov[1].iov_base, buf, copy);
 276
 277 done:
 278     /* Update fields */
 279         sb->sb_cc += size;
 280         sb->sb_wptr += size;
 281         if (sb->sb_wptr >= (sb->sb_data + sb->sb_datalen))
 282                 sb->sb_wptr -= sb->sb_datalen;
 283     return size;
 284 err:
 285
 286     sofcantrcvmore(so);
 287     tcp_sockclosed(sototcpcb(so));
 288     g_critical("soreadbuf buffer too small");
 289     return -1;
 290 }
 291
 292 /*
 293  * Get urgent data
 294  *
 295  * When the socket is created, we set it SO_OOBINLINE,
 296  * so when OOB data arrives, we soread() it and everything
 297  * in the send buffer is sent as urgent data
 298  */
 299 int
 300 sorecvoob(struct socket *so)
 301 {
 302         struct tcpcb *tp = sototcpcb(so);
 303         int ret;
 304
 305         DEBUG_CALL("sorecvoob");
 306         DEBUG_ARG("so = %p", so);
 307
 308         /*
 309          * We take a guess at how much urgent data has arrived.
 310          * In most situations, when urgent data arrives, the next
 311          * read() should get all the urgent data.  This guess will
 312          * be wrong however if more data arrives just after the
 313          * urgent data, or the read() doesn't return all the
 314          * urgent data.
 315          */
 316         ret = soread(so);
 317         if (ret > 0) {
 318             tp->snd_up = tp->snd_una + so->so_snd.sb_cc;
 319             tp->t_force = 1;
 320             tcp_output(tp);
 321             tp->t_force = 0;
 322         }
 323
 324         return ret;
 325 }
 326
 327 /*
 328  * Send urgent data
 329  * There's a lot duplicated code here, but...
 330  */
 331 int
 332 sosendoob(struct socket *so)
 333 {
 334         struct sbuf *sb = &so->so_rcv;
 335         char buff[2048]; /* XXX Shouldn't be sending more oob data than this */
 336
 337         int n;
 338
 339         DEBUG_CALL("sosendoob");
 340         DEBUG_ARG("so = %p", so);
 341         DEBUG_ARG("sb->sb_cc = %d", sb->sb_cc);
 342
 343         if (so->so_urgc > 2048)
 344            so->so_urgc = 2048; /* XXXX */
 345
 346         if (sb->sb_rptr < sb->sb_wptr) {
 347                 /* We can send it directly */
 348                 n = slirp_send(so, sb->sb_rptr, so->so_urgc, (MSG_OOB)); /* |MSG_DONTWAIT)); */
 349         } else {
 350                 /*
 351                  * Since there's no sendv or sendtov like writev,
 352                  * we must copy all data to a linear buffer then
 353                  * send it all
 354                  */
 355                 uint32_t urgc = so->so_urgc;
 356                 int len = (sb->sb_data + sb->sb_datalen) - sb->sb_rptr;
 357                 if (len > urgc) {
 358                         len = urgc;
 359                 }
 360                 memcpy(buff, sb->sb_rptr, len);
 361                 urgc -= len;
 362                 if (urgc) {
 363                         n = sb->sb_wptr - sb->sb_data;
 364                         if (n > urgc) {
 365                                 n = urgc;
 366                         }
 367                         memcpy((buff + len), sb->sb_data, n);
 368                         len += n;
 369                 }
 370                 n = slirp_send(so, buff, len, (MSG_OOB)); /* |MSG_DONTWAIT)); */
 371 #ifdef DEBUG
 372                 if (n != len) {
 373                         DEBUG_ERROR("Didn't send all data urgently XXXXX");
 374                 }
 375 #endif
 376         }
 377
 378         if (n < 0) {
 379                 return n;
 380         }
 381         so->so_urgc -= n;
 382         DEBUG_MISC(" ---2 sent %d bytes urgent data, %d urgent bytes left", n, so->so_urgc);
 383
 384         sb->sb_cc -= n;
 385         sb->sb_rptr += n;
 386         if (sb->sb_rptr >= (sb->sb_data + sb->sb_datalen))
 387                 sb->sb_rptr -= sb->sb_datalen;
 388
 389         return n;
 390 }
 391
 392 /*
 393  * Write data from so_rcv to so's socket,
 394  * updating all sbuf field as necessary
 395  */
 396 int
 397 sowrite(struct socket *so)
 398 {
 399         int  n,nn;
 400         struct sbuf *sb = &so->so_rcv;
 401         int len = sb->sb_cc;
 402         struct iovec iov[2];
 403
 404         DEBUG_CALL("sowrite");
 405         DEBUG_ARG("so = %p", so);
 406
 407         if (so->so_urgc) {
 408                 uint32_t expected = so->so_urgc;
 409                 if (sosendoob(so) < expected) {
 410                         /* Treat a short write as a fatal error too,
 411                          * rather than continuing on and sending the urgent
 412                          * data as if it were non-urgent and leaving the
 413                          * so_urgc count wrong.
 414                          */
 415                         goto err_disconnected;
 416                 }
 417                 if (sb->sb_cc == 0)
 418                         return 0;
 419         }
 420
 421         /*
 422          * No need to check if there's something to write,
 423          * sowrite wouldn't have been called otherwise
 424          */
 425
 426         iov[0].iov_base = sb->sb_rptr;
 427         iov[1].iov_base = NULL;
 428         iov[1].iov_len = 0;
 429         if (sb->sb_rptr < sb->sb_wptr) {
 430                 iov[0].iov_len = sb->sb_wptr - sb->sb_rptr;
 431                 /* Should never succeed, but... */
 432                 if (iov[0].iov_len > len) iov[0].iov_len = len;
 433                 n = 1;
 434         } else {
 435                 iov[0].iov_len = (sb->sb_data + sb->sb_datalen) - sb->sb_rptr;
 436                 if (iov[0].iov_len > len) iov[0].iov_len = len;
 437                 len -= iov[0].iov_len;
 438                 if (len) {
 439                         iov[1].iov_base = sb->sb_data;
 440                         iov[1].iov_len = sb->sb_wptr - sb->sb_data;
 441                         if (iov[1].iov_len > len) iov[1].iov_len = len;
 442                         n = 2;
 443                 } else
 444                         n = 1;
 445         }
 446         /* Check if there's urgent data to send, and if so, send it */
 447
 448         nn = slirp_send(so, iov[0].iov_base, iov[0].iov_len,0);
 449         /* This should never happen, but people tell me it does *shrug* */
 450         if (nn < 0 && (errno == EAGAIN || errno == EINTR))
 451                 return 0;
 452
 453         if (nn <= 0) {
 454                 goto err_disconnected;
 455         }
 456
 457         if (n == 2 && nn == iov[0].iov_len) {
 458             int ret;
 459             ret = slirp_send(so, iov[1].iov_base, iov[1].iov_len,0);
 460             if (ret > 0)
 461                 nn += ret;
 462         }
 463         DEBUG_MISC("  ... wrote nn = %d bytes", nn);
 464
 465         /* Update sbuf */
 466         sb->sb_cc -= nn;
 467         sb->sb_rptr += nn;
 468         if (sb->sb_rptr >= (sb->sb_data + sb->sb_datalen))
 469                 sb->sb_rptr -= sb->sb_datalen;
 470
 471         /*
 472          * If in DRAIN mode, and there's no more data, set
 473          * it CANTSENDMORE
 474          */
 475         if ((so->so_state & SS_FWDRAIN) && sb->sb_cc == 0)
 476                 sofcantsendmore(so);
 477
 478         return nn;
 479
 480 err_disconnected:
 481         DEBUG_MISC(" --- sowrite disconnected, so->so_state = %x, errno = %d",
 482                so->so_state, errno);
 483         sofcantsendmore(so);
 484         tcp_sockclosed(sototcpcb(so));
 485         return -1;
 486 }
 487
 488 /*
 489  * recvfrom() a UDP socket
 490  */
 491 void
 492 sorecvfrom(struct socket *so)
 493 {
 494         struct sockaddr_storage addr;
 495         struct sockaddr_storage saddr, daddr;
 496         socklen_t addrlen = sizeof(struct sockaddr_storage);
 497
 498         DEBUG_CALL("sorecvfrom");
 499         DEBUG_ARG("so = %p", so);
 500
 501         if (so->so_type == IPPROTO_ICMP) {   /* This is a "ping" reply */
 502           char buff[256];
 503           int len;
 504
 505           len = recvfrom(so->s, buff, 256, 0,
 506                          (struct sockaddr *)&addr, &addrlen);
 507           /* XXX Check if reply is "correct"? */
 508
 509           if(len == -1 || len == 0) {
 510             uint8_t code=ICMP_UNREACH_PORT;
 511
 512             if(errno == EHOSTUNREACH) code=ICMP_UNREACH_HOST;
 513             else if(errno == ENETUNREACH) code=ICMP_UNREACH_NET;
 514
 515             DEBUG_MISC(" udp icmp rx errno = %d-%s",
 516                    errno,strerror(errno));
 517             icmp_send_error(so->so_m, ICMP_UNREACH, code, 0, strerror(errno));
 518           } else {
 519             icmp_reflect(so->so_m);
 520             so->so_m = NULL; /* Don't m_free() it again! */
 521           }
 522           /* No need for this socket anymore, udp_detach it */
 523           udp_detach(so);
 524         } else {                                /* A "normal" UDP packet */
 525           struct mbuf *m;
 526           int len;
 527 #ifdef _WIN32
 528           unsigned long n;
 529 #else
 530           int n;
 531 #endif
 532
 533           if (ioctlsocket(so->s, FIONREAD, &n) != 0) {
 534               DEBUG_MISC(" ioctlsocket errno = %d-%s\n",
 535                          errno,strerror(errno));
 536               return;
 537           }
 538           if (n == 0) {
 539               return;
 540           }
 541
 542           m = m_get(so->slirp);
 543           if (!m) {
 544               return;
 545           }
 546           switch (so->so_ffamily) {
 547           case AF_INET:
 548               m->m_data += IF_MAXLINKHDR + sizeof(struct udpiphdr);
 549               break;
 550           case AF_INET6:
 551               m->m_data += IF_MAXLINKHDR + sizeof(struct ip6)
 552                                          + sizeof(struct udphdr);
 553               break;
 554           default:
 555               g_assert_not_reached();
 556               break;
 557           }
 558
 559           /*
 560            * XXX Shouldn't FIONREAD packets destined for port 53,
 561            * but I don't know the max packet size for DNS lookups
 562            */
 563           len = M_FREEROOM(m);
 564           /* if (so->so_fport != htons(53)) { */
 565
 566           if (n > len) {
 567             n = (m->m_data - m->m_dat) + m->m_len + n + 1;
 568             m_inc(m, n);
 569             len = M_FREEROOM(m);
 570           }
 571           /* } */
 572
 573           m->m_len = recvfrom(so->s, m->m_data, len, 0,
 574                               (struct sockaddr *)&addr, &addrlen);
 575           DEBUG_MISC(" did recvfrom %d, errno = %d-%s",
 576                  m->m_len, errno,strerror(errno));
 577           if(m->m_len<0) {
 578             /* Report error as ICMP */
 579             switch (so->so_lfamily) {
 580             uint8_t code;
 581             case AF_INET:
 582               code = ICMP_UNREACH_PORT;
 583
 584               if (errno == EHOSTUNREACH) {
 585                 code = ICMP_UNREACH_HOST;
 586               } else if (errno == ENETUNREACH) {
 587                 code = ICMP_UNREACH_NET;
 588               }
 589
 590               DEBUG_MISC(" rx error, tx icmp ICMP_UNREACH:%i", code);
 591               icmp_send_error(so->so_m, ICMP_UNREACH, code, 0, strerror(errno));
 592               break;
 593             case AF_INET6:
 594               code = ICMP6_UNREACH_PORT;
 595
 596               if (errno == EHOSTUNREACH) {
 597                 code = ICMP6_UNREACH_ADDRESS;
 598               } else if (errno == ENETUNREACH) {
 599                 code = ICMP6_UNREACH_NO_ROUTE;
 600               }
 601
 602               DEBUG_MISC(" rx error, tx icmp6 ICMP_UNREACH:%i", code);
 603               icmp6_send_error(so->so_m, ICMP6_UNREACH, code);
 604               break;
 605             default:
 606               g_assert_not_reached();
 607               break;
 608             }
 609             m_free(m);
 610           } else {
 611           /*
 612            * Hack: domain name lookup will be used the most for UDP,
 613            * and since they'll only be used once there's no need
 614            * for the 4 minute (or whatever) timeout... So we time them
 615            * out much quicker (10 seconds  for now...)
 616            */
 617             if (so->so_expire) {
 618               if (so->so_fport == htons(53))
 619                 so->so_expire = curtime + SO_EXPIREFAST;
 620               else
 621                 so->so_expire = curtime + SO_EXPIRE;
 622             }
 623
 624             /*
 625              * If this packet was destined for CTL_ADDR,
 626              * make it look like that's where it came from
 627              */
 628             saddr = addr;
 629             sotranslate_in(so, &saddr);
 630             daddr = so->lhost.ss;
 631
 632             switch (so->so_ffamily) {
 633             case AF_INET:
 634                 udp_output(so, m, (struct sockaddr_in *) &saddr,
 635                            (struct sockaddr_in *) &daddr,
 636                            so->so_iptos);
 637                 break;
 638             case AF_INET6:
 639                 udp6_output(so, m, (struct sockaddr_in6 *) &saddr,
 640                             (struct sockaddr_in6 *) &daddr);
 641                 break;
 642             default:
 643                 g_assert_not_reached();
 644                 break;
 645             }
 646           } /* rx error */
 647         } /* if ping packet */
 648 }
 649
 650 /*
 651  * sendto() a socket
 652  */
 653 int
 654 sosendto(struct socket *so, struct mbuf *m)
 655 {
 656         int ret;
 657         struct sockaddr_storage addr;
 658
 659         DEBUG_CALL("sosendto");
 660         DEBUG_ARG("so = %p", so);
 661         DEBUG_ARG("m = %p", m);
 662
 663         addr = so->fhost.ss;
 664         DEBUG_CALL(" sendto()ing)");
 665         sotranslate_out(so, &addr);
 666
 667         /* Don't care what port we get */
 668         ret = sendto(so->s, m->m_data, m->m_len, 0,
 669                      (struct sockaddr *)&addr, sockaddr_size(&addr));
 670         if (ret < 0)
 671                 return -1;
 672
 673         /*
 674          * Kill the socket if there's no reply in 4 minutes,
 675          * but only if it's an expirable socket
 676          */
 677         if (so->so_expire)
 678                 so->so_expire = curtime + SO_EXPIRE;
 679         so->so_state &= SS_PERSISTENT_MASK;
 680         so->so_state |= SS_ISFCONNECTED; /* So that it gets select()ed */
 681         return 0;
 682 }
 683
 684 /*
 685  * Listen for incoming TCP connections
 686  */
 687 struct socket *
 688 tcp_listen(Slirp *slirp, uint32_t haddr, unsigned hport, uint32_t laddr,
 689            unsigned lport, int flags)
 690 {
 691         /* TODO: IPv6 */
 692         struct sockaddr_in addr;
 693         struct socket *so;
 694         int s, opt = 1;
 695         socklen_t addrlen = sizeof(addr);
 696         memset(&addr, 0, addrlen);
 697
 698         DEBUG_CALL("tcp_listen");
 699         DEBUG_ARG("haddr = %s", inet_ntoa((struct in_addr){.s_addr = haddr}));
 700         DEBUG_ARG("hport = %d", ntohs(hport));
 701         DEBUG_ARG("laddr = %s", inet_ntoa((struct in_addr){.s_addr = laddr}));
 702         DEBUG_ARG("lport = %d", ntohs(lport));
 703         DEBUG_ARG("flags = %x", flags);
 704
 705         so = socreate(slirp);
 706
 707         /* Don't tcp_attach... we don't need so_snd nor so_rcv */
 708         if ((so->so_tcpcb = tcp_newtcpcb(so)) == NULL) {
 709             g_free(so);
 710             return NULL;
 711         }
 712         insque(so, &slirp->tcb);
 713
 714         /*
 715          * SS_FACCEPTONCE sockets must time out.
 716          */
 717         if (flags & SS_FACCEPTONCE)
 718            so->so_tcpcb->t_timer[TCPT_KEEP] = TCPTV_KEEP_INIT*2;
 719
 720         so->so_state &= SS_PERSISTENT_MASK;
 721         so->so_state |= (SS_FACCEPTCONN | flags);
 722         so->so_lfamily = AF_INET;
 723         so->so_lport = lport; /* Kept in network format */
 724         so->so_laddr.s_addr = laddr; /* Ditto */
 725
 726         addr.sin_family = AF_INET;
 727         addr.sin_addr.s_addr = haddr;
 728         addr.sin_port = hport;
 729
 730         if (((s = slirp_socket(AF_INET,SOCK_STREAM,0)) < 0) ||
 731             (slirp_socket_set_fast_reuse(s) < 0) ||
 732             (bind(s,(struct sockaddr *)&addr, sizeof(addr)) < 0) ||
 733             (listen(s,1) < 0)) {
 734                 int tmperrno = errno; /* Don't clobber the real reason we failed */
 735
 736                 if (s >= 0) {
 737                     closesocket(s);
 738                 }
 739                 sofree(so);
 740                 /* Restore the real errno */
 741 #ifdef _WIN32
 742                 WSASetLastError(tmperrno);
 743 #else
 744                 errno = tmperrno;
 745 #endif
 746                 return NULL;
 747         }
 748         setsockopt(s, SOL_SOCKET, SO_OOBINLINE, &opt, sizeof(int));
 749         opt = 1;
 750         setsockopt(s, IPPROTO_TCP, TCP_NODELAY, &opt, sizeof(int));
 751
 752         getsockname(s,(struct sockaddr *)&addr,&addrlen);
 753         so->so_ffamily = AF_INET;
 754         so->so_fport = addr.sin_port;
 755         if (addr.sin_addr.s_addr == 0 || addr.sin_addr.s_addr == loopback_addr.s_addr)
 756            so->so_faddr = slirp->vhost_addr;
 757         else
 758            so->so_faddr = addr.sin_addr;
 759
 760         so->s = s;
 761         return so;
 762 }
 763
 764 /*
 765  * Various session state calls
 766  * XXX Should be #define's
 767  * The socket state stuff needs work, these often get call 2 or 3
 768  * times each when only 1 was needed
 769  */
 770 void
 771 soisfconnecting(struct socket *so)
 772 {
 773         so->so_state &= ~(SS_NOFDREF|SS_ISFCONNECTED|SS_FCANTRCVMORE|
 774                           SS_FCANTSENDMORE|SS_FWDRAIN);
 775         so->so_state |= SS_ISFCONNECTING; /* Clobber other states */
 776 }
 777
 778 void
 779 soisfconnected(struct socket *so)
 780 {
 781         so->so_state &= ~(SS_ISFCONNECTING|SS_FWDRAIN|SS_NOFDREF);
 782         so->so_state |= SS_ISFCONNECTED; /* Clobber other states */
 783 }
 784
 785 static void
 786 sofcantrcvmore(struct socket *so)
 787 {
 788         if ((so->so_state & SS_NOFDREF) == 0) {
 789                 shutdown(so->s,0);
 790         }
 791         so->so_state &= ~(SS_ISFCONNECTING);
 792         if (so->so_state & SS_FCANTSENDMORE) {
 793            so->so_state &= SS_PERSISTENT_MASK;
 794            so->so_state |= SS_NOFDREF; /* Don't select it */
 795         } else {
 796            so->so_state |= SS_FCANTRCVMORE;
 797         }
 798 }
 799
 800 static void
 801 sofcantsendmore(struct socket *so)
 802 {
 803         if ((so->so_state & SS_NOFDREF) == 0) {
 804             shutdown(so->s,1);           /* send FIN to fhost */
 805         }
 806         so->so_state &= ~(SS_ISFCONNECTING);
 807         if (so->so_state & SS_FCANTRCVMORE) {
 808            so->so_state &= SS_PERSISTENT_MASK;
 809            so->so_state |= SS_NOFDREF; /* as above */
 810         } else {
 811            so->so_state |= SS_FCANTSENDMORE;
 812         }
 813 }
 814
 815 /*
 816  * Set write drain mode
 817  * Set CANTSENDMORE once all data has been write()n
 818  */
 819 void
 820 sofwdrain(struct socket *so)
 821 {
 822         if (so->so_rcv.sb_cc)
 823                 so->so_state |= SS_FWDRAIN;
 824         else
 825                 sofcantsendmore(so);
 826 }
 827
 828 /*
 829  * Translate addr in host addr when it is a virtual address
 830  */
 831 void sotranslate_out(struct socket *so, struct sockaddr_storage *addr)
 832 {
 833     Slirp *slirp = so->slirp;
 834     struct sockaddr_in *sin = (struct sockaddr_in *)addr;
 835     struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)addr;
 836
 837     switch (addr->ss_family) {
 838     case AF_INET:
 839         if ((so->so_faddr.s_addr & slirp->vnetwork_mask.s_addr) ==
 840                 slirp->vnetwork_addr.s_addr) {
 841             /* It's an alias */
 842             if (so->so_faddr.s_addr == slirp->vnameserver_addr.s_addr) {
 843                 if (get_dns_addr(&sin->sin_addr) < 0) {
 844                     sin->sin_addr = loopback_addr;
 845                 }
 846             } else {
 847                 sin->sin_addr = loopback_addr;
 848             }
 849         }
 850
 851         DEBUG_MISC(" addr.sin_port=%d, addr.sin_addr.s_addr=%.16s",
 852                    ntohs(sin->sin_port), inet_ntoa(sin->sin_addr));
 853         break;
 854
 855     case AF_INET6:
 856         if (in6_equal_net(&so->so_faddr6, &slirp->vprefix_addr6,
 857                     slirp->vprefix_len)) {
 858             if (in6_equal(&so->so_faddr6, &slirp->vnameserver_addr6)) {
 859                 uint32_t scope_id;
 860                 if (get_dns6_addr(&sin6->sin6_addr, &scope_id) >= 0) {
 861                     sin6->sin6_scope_id = scope_id;
 862                 } else {
 863                     sin6->sin6_addr = in6addr_loopback;
 864                 }
 865             } else {
 866                 sin6->sin6_addr = in6addr_loopback;
 867             }
 868         }
 869         break;
 870
 871     default:
 872         break;
 873     }
 874 }
 875
 876 void sotranslate_in(struct socket *so, struct sockaddr_storage *addr)
 877 {
 878     Slirp *slirp = so->slirp;
 879     struct sockaddr_in *sin = (struct sockaddr_in *)addr;
 880     struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)addr;
 881
 882     switch (addr->ss_family) {
 883     case AF_INET:
 884         if ((so->so_faddr.s_addr & slirp->vnetwork_mask.s_addr) ==
 885             slirp->vnetwork_addr.s_addr) {
 886             uint32_t inv_mask = ~slirp->vnetwork_mask.s_addr;
 887
 888             if ((so->so_faddr.s_addr & inv_mask) == inv_mask) {
 889                 sin->sin_addr = slirp->vhost_addr;
 890             } else if (sin->sin_addr.s_addr == loopback_addr.s_addr ||
 891                        so->so_faddr.s_addr != slirp->vhost_addr.s_addr) {
 892                 sin->sin_addr = so->so_faddr;
 893             }
 894         }
 895         break;
 896
 897     case AF_INET6:
 898         if (in6_equal_net(&so->so_faddr6, &slirp->vprefix_addr6,
 899                     slirp->vprefix_len)) {
 900             if (in6_equal(&sin6->sin6_addr, &in6addr_loopback)
 901                     || !in6_equal(&so->so_faddr6, &slirp->vhost_addr6)) {
 902                 sin6->sin6_addr = so->so_faddr6;
 903             }
 904         }
 905         break;
 906
 907     default:
 908         break;
 909     }
 910 }
 911
 912 /*
 913  * Translate connections from localhost to the real hostname
 914  */
 915 void sotranslate_accept(struct socket *so)
 916 {
 917     Slirp *slirp = so->slirp;
 918
 919     switch (so->so_ffamily) {
 920     case AF_INET:
 921         if (so->so_faddr.s_addr == INADDR_ANY ||
 922             (so->so_faddr.s_addr & loopback_mask) ==
 923             (loopback_addr.s_addr & loopback_mask)) {
 924            so->so_faddr = slirp->vhost_addr;
 925         }
 926         break;
 927
 928    case AF_INET6:
 929         if (in6_equal(&so->so_faddr6, &in6addr_any) ||
 930                 in6_equal(&so->so_faddr6, &in6addr_loopback)) {
 931            so->so_faddr6 = slirp->vhost_addr6;
 932         }
 933         break;
 934
 935     default:
 936         break;
 937     }
 938 }
 939
 940 void sodrop(struct socket *s, int num)
 941 {
 942     if (sbdrop(&s->so_snd, num)) {
 943         s->slirp->cb->notify(s->slirp->opaque);
 944     }
 945 }