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1
/*
2
 * Copyright (c) 1982, 1986, 1988, 1990, 1993
3
 *        The Regents of the University of California.  All rights reserved.
4
 *
5
 * Redistribution and use in source and binary forms, with or without
6
 * modification, are permitted provided that the following conditions
7
 * are met:
8
 * 1. Redistributions of source code must retain the above copyright
9
 *    notice, this list of conditions and the following disclaimer.
10
 * 2. Redistributions in binary form must reproduce the above copyright
11
 *    notice, this list of conditions and the following disclaimer in the
12
 *    documentation and/or other materials provided with the distribution.
13
 * 3. All advertising materials mentioning features or use of this software
14
 *    must display the following acknowledgement:
15
 *        This product includes software developed by the University of
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 *        California, Berkeley and its contributors.
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 * 4. Neither the name of the University nor the names of its contributors
18
 *    may be used to endorse or promote products derived from this software
19
 *    without specific prior written permission.
20
 *
21
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31
 * SUCH DAMAGE.
32
 *
33
 *        @(#)udp_usrreq.c        8.4 (Berkeley) 1/21/94
34
 * udp_usrreq.c,v 1.4 1994/10/02 17:48:45 phk Exp
35
 */
36

    
37
/*
38
 * Changes and additions relating to SLiRP
39
 * Copyright (c) 1995 Danny Gasparovski.
40
 *
41
 * Please read the file COPYRIGHT for the
42
 * terms and conditions of the copyright.
43
 */
44

    
45
#include <slirp.h>
46
#include "ip_icmp.h"
47

    
48
struct udpstat udpstat;
49

    
50
struct socket udb;
51

    
52
/*
53
 * UDP protocol implementation.
54
 * Per RFC 768, August, 1980.
55
 */
56
#ifndef        COMPAT_42
57
int        udpcksum = 1;
58
#else
59
int        udpcksum = 0;                /* XXX */
60
#endif
61

    
62
struct        socket *udp_last_so = &udb;
63

    
64
void
65
udp_init()
66
{
67
        udb.so_next = udb.so_prev = &udb;
68
}
69
/* m->m_data  points at ip packet header
70
 * m->m_len   length ip packet
71
 * ip->ip_len length data (IPDU)
72
 */
73
void
74
udp_input(m, iphlen)
75
        register struct mbuf *m;
76
        int iphlen;
77
{
78
        register struct ip *ip;
79
        register struct udphdr *uh;
80
/*        struct mbuf *opts = 0;*/
81
        int len;
82
        struct ip save_ip;
83
        struct socket *so;
84

    
85
        DEBUG_CALL("udp_input");
86
        DEBUG_ARG("m = %lx", (long)m);
87
        DEBUG_ARG("iphlen = %d", iphlen);
88

    
89
        udpstat.udps_ipackets++;
90

    
91
        /*
92
         * Strip IP options, if any; should skip this,
93
         * make available to user, and use on returned packets,
94
         * but we don't yet have a way to check the checksum
95
         * with options still present.
96
         */
97
        if(iphlen > sizeof(struct ip)) {
98
                ip_stripoptions(m, (struct mbuf *)0);
99
                iphlen = sizeof(struct ip);
100
        }
101

    
102
        /*
103
         * Get IP and UDP header together in first mbuf.
104
         */
105
        ip = mtod(m, struct ip *);
106
        uh = (struct udphdr *)((caddr_t)ip + iphlen);
107

    
108
        /*
109
         * Make mbuf data length reflect UDP length.
110
         * If not enough data to reflect UDP length, drop.
111
         */
112
        len = ntohs((u_int16_t)uh->uh_ulen);
113

    
114
        if (ip->ip_len != len) {
115
                if (len > ip->ip_len) {
116
                        udpstat.udps_badlen++;
117
                        goto bad;
118
                }
119
                m_adj(m, len - ip->ip_len);
120
                ip->ip_len = len;
121
        }
122

    
123
        /*
124
         * Save a copy of the IP header in case we want restore it
125
         * for sending an ICMP error message in response.
126
         */
127
        save_ip = *ip;
128
        save_ip.ip_len+= iphlen;         /* tcp_input subtracts this */
129

    
130
        /*
131
         * Checksum extended UDP header and data.
132
         */
133
        if (udpcksum && uh->uh_sum) {
134
          ((struct ipovly *)ip)->ih_next = 0;
135
          ((struct ipovly *)ip)->ih_prev = 0;
136
          ((struct ipovly *)ip)->ih_x1 = 0;
137
          ((struct ipovly *)ip)->ih_len = uh->uh_ulen;
138
          /* keep uh_sum for ICMP reply
139
           * uh->uh_sum = cksum(m, len + sizeof (struct ip));
140
           * if (uh->uh_sum) {
141
           */
142
          if(cksum(m, len + sizeof(struct ip))) {
143
            udpstat.udps_badsum++;
144
            goto bad;
145
          }
146
        }
147

    
148
        /*
149
         *  handle DHCP/BOOTP
150
         */
151
        if (ntohs(uh->uh_dport) == BOOTP_SERVER) {
152
            bootp_input(m);
153
            goto bad;
154
        }
155

    
156
        /*
157
         *  handle TFTP
158
         */
159
        if (ntohs(uh->uh_dport) == TFTP_SERVER) {
160
            tftp_input(m);
161
            goto bad;
162
        }
163

    
164
        /*
165
         * Locate pcb for datagram.
166
         */
167
        so = udp_last_so;
168
        if (so->so_lport != uh->uh_sport ||
169
            so->so_laddr.s_addr != ip->ip_src.s_addr) {
170
                struct socket *tmp;
171

    
172
                for (tmp = udb.so_next; tmp != &udb; tmp = tmp->so_next) {
173
                        if (tmp->so_lport == uh->uh_sport &&
174
                            tmp->so_laddr.s_addr == ip->ip_src.s_addr) {
175
                                tmp->so_faddr.s_addr = ip->ip_dst.s_addr;
176
                                tmp->so_fport = uh->uh_dport;
177
                                so = tmp;
178
                                break;
179
                        }
180
                }
181
                if (tmp == &udb) {
182
                  so = NULL;
183
                } else {
184
                  udpstat.udpps_pcbcachemiss++;
185
                  udp_last_so = so;
186
                }
187
        }
188

    
189
        if (so == NULL) {
190
          /*
191
           * If there's no socket for this packet,
192
           * create one
193
           */
194
          if ((so = socreate()) == NULL) goto bad;
195
          if(udp_attach(so) == -1) {
196
            DEBUG_MISC((dfd," udp_attach errno = %d-%s\n",
197
                        errno,strerror(errno)));
198
            sofree(so);
199
            goto bad;
200
          }
201

    
202
          /*
203
           * Setup fields
204
           */
205
          /* udp_last_so = so; */
206
          so->so_laddr = ip->ip_src;
207
          so->so_lport = uh->uh_sport;
208

    
209
          if ((so->so_iptos = udp_tos(so)) == 0)
210
            so->so_iptos = ip->ip_tos;
211

    
212
          /*
213
           * XXXXX Here, check if it's in udpexec_list,
214
           * and if it is, do the fork_exec() etc.
215
           */
216
        }
217

    
218
        so->so_faddr = ip->ip_dst; /* XXX */
219
        so->so_fport = uh->uh_dport; /* XXX */
220

    
221
        iphlen += sizeof(struct udphdr);
222
        m->m_len -= iphlen;
223
        m->m_data += iphlen;
224

    
225
        /*
226
         * Now we sendto() the packet.
227
         */
228
        if (so->so_emu)
229
           udp_emu(so, m);
230

    
231
        if(sosendto(so,m) == -1) {
232
          m->m_len += iphlen;
233
          m->m_data -= iphlen;
234
          *ip=save_ip;
235
          DEBUG_MISC((dfd,"udp tx errno = %d-%s\n",errno,strerror(errno)));
236
          icmp_error(m, ICMP_UNREACH,ICMP_UNREACH_NET, 0,strerror(errno));
237
        }
238

    
239
        m_free(so->so_m);   /* used for ICMP if error on sorecvfrom */
240

    
241
        /* restore the orig mbuf packet */
242
        m->m_len += iphlen;
243
        m->m_data -= iphlen;
244
        *ip=save_ip;
245
        so->so_m=m;         /* ICMP backup */
246

    
247
        return;
248
bad:
249
        m_freem(m);
250
        /* if (opts) m_freem(opts); */
251
        return;
252
}
253

    
254
int udp_output2(struct socket *so, struct mbuf *m,
255
                struct sockaddr_in *saddr, struct sockaddr_in *daddr,
256
                int iptos)
257
{
258
        register struct udpiphdr *ui;
259
        int error = 0;
260

    
261
        DEBUG_CALL("udp_output");
262
        DEBUG_ARG("so = %lx", (long)so);
263
        DEBUG_ARG("m = %lx", (long)m);
264
        DEBUG_ARG("saddr = %lx", (long)saddr->sin_addr.s_addr);
265
        DEBUG_ARG("daddr = %lx", (long)daddr->sin_addr.s_addr);
266

    
267
        /*
268
         * Adjust for header
269
         */
270
        m->m_data -= sizeof(struct udpiphdr);
271
        m->m_len += sizeof(struct udpiphdr);
272

    
273
        /*
274
         * Fill in mbuf with extended UDP header
275
         * and addresses and length put into network format.
276
         */
277
        ui = mtod(m, struct udpiphdr *);
278
        ui->ui_next = ui->ui_prev = 0;
279
        ui->ui_x1 = 0;
280
        ui->ui_pr = IPPROTO_UDP;
281
        ui->ui_len = htons(m->m_len - sizeof(struct ip)); /* + sizeof (struct udphdr)); */
282
        /* XXXXX Check for from-one-location sockets, or from-any-location sockets */
283
        ui->ui_src = saddr->sin_addr;
284
        ui->ui_dst = daddr->sin_addr;
285
        ui->ui_sport = saddr->sin_port;
286
        ui->ui_dport = daddr->sin_port;
287
        ui->ui_ulen = ui->ui_len;
288

    
289
        /*
290
         * Stuff checksum and output datagram.
291
         */
292
        ui->ui_sum = 0;
293
        if (udpcksum) {
294
            if ((ui->ui_sum = cksum(m, /* sizeof (struct udpiphdr) + */ m->m_len)) == 0)
295
                ui->ui_sum = 0xffff;
296
        }
297
        ((struct ip *)ui)->ip_len = m->m_len;
298

    
299
        ((struct ip *)ui)->ip_ttl = ip_defttl;
300
        ((struct ip *)ui)->ip_tos = iptos;
301

    
302
        udpstat.udps_opackets++;
303

    
304
        error = ip_output(so, m);
305

    
306
        return (error);
307
}
308

    
309
int udp_output(struct socket *so, struct mbuf *m,
310
               struct sockaddr_in *addr)
311

    
312
{
313
    struct sockaddr_in saddr, daddr;
314

    
315
    saddr = *addr;
316
    if ((so->so_faddr.s_addr & htonl(0xffffff00)) == special_addr.s_addr) {
317
        saddr.sin_addr.s_addr = so->so_faddr.s_addr;
318
        if ((so->so_faddr.s_addr & htonl(0x000000ff)) == htonl(0xff))
319
            saddr.sin_addr.s_addr = alias_addr.s_addr;
320
    }
321
    daddr.sin_addr = so->so_laddr;
322
    daddr.sin_port = so->so_lport;
323

    
324
    return udp_output2(so, m, &saddr, &daddr, so->so_iptos);
325
}
326

    
327
int
328
udp_attach(so)
329
     struct socket *so;
330
{
331
  struct sockaddr_in addr;
332

    
333
  if((so->s = socket(AF_INET,SOCK_DGRAM,0)) != -1) {
334
    /*
335
     * Here, we bind() the socket.  Although not really needed
336
     * (sendto() on an unbound socket will bind it), it's done
337
     * here so that emulation of ytalk etc. don't have to do it
338
     */
339
    addr.sin_family = AF_INET;
340
    addr.sin_port = 0;
341
    addr.sin_addr.s_addr = INADDR_ANY;
342
    if(bind(so->s, (struct sockaddr *)&addr, sizeof(addr))<0) {
343
      int lasterrno=errno;
344
      closesocket(so->s);
345
      so->s=-1;
346
#ifdef _WIN32
347
      WSASetLastError(lasterrno);
348
#else
349
      errno=lasterrno;
350
#endif
351
    } else {
352
      /* success, insert in queue */
353
      so->so_expire = curtime + SO_EXPIRE;
354
      insque(so,&udb);
355
    }
356
  }
357
  return(so->s);
358
}
359

    
360
void
361
udp_detach(so)
362
        struct socket *so;
363
{
364
        closesocket(so->s);
365
        /* if (so->so_m) m_free(so->so_m);    done by sofree */
366

    
367
        sofree(so);
368
}
369

    
370
struct tos_t udptos[] = {
371
        {0, 53, IPTOS_LOWDELAY, 0},                        /* DNS */
372
        {517, 517, IPTOS_LOWDELAY, EMU_TALK},        /* talk */
373
        {518, 518, IPTOS_LOWDELAY, EMU_NTALK},        /* ntalk */
374
        {0, 7648, IPTOS_LOWDELAY, EMU_CUSEEME},        /* Cu-Seeme */
375
        {0, 0, 0, 0}
376
};
377

    
378
u_int8_t
379
udp_tos(so)
380
        struct socket *so;
381
{
382
        int i = 0;
383

    
384
        while(udptos[i].tos) {
385
                if ((udptos[i].fport && ntohs(so->so_fport) == udptos[i].fport) ||
386
                    (udptos[i].lport && ntohs(so->so_lport) == udptos[i].lport)) {
387
                            so->so_emu = udptos[i].emu;
388
                        return udptos[i].tos;
389
                }
390
                i++;
391
        }
392

    
393
        return 0;
394
}
395

    
396
#ifdef EMULATE_TALK
397
#include "talkd.h"
398
#endif
399

    
400
/*
401
 * Here, talk/ytalk/ntalk requests must be emulated
402
 */
403
void
404
udp_emu(so, m)
405
        struct socket *so;
406
        struct mbuf *m;
407
{
408
        struct sockaddr_in addr;
409
        int addrlen = sizeof(addr);
410
#ifdef EMULATE_TALK
411
        CTL_MSG_OLD *omsg;
412
        CTL_MSG *nmsg;
413
        char buff[sizeof(CTL_MSG)];
414
        u_char type;
415

    
416
struct talk_request {
417
        struct talk_request *next;
418
        struct socket *udp_so;
419
        struct socket *tcp_so;
420
} *req;
421

    
422
        static struct talk_request *req_tbl = 0;
423

    
424
#endif
425

    
426
struct cu_header {
427
        uint16_t        d_family;                // destination family
428
        uint16_t        d_port;                        // destination port
429
        uint32_t        d_addr;                        // destination address
430
        uint16_t        s_family;                // source family
431
        uint16_t        s_port;                        // source port
432
        uint32_t        so_addr;                // source address
433
        uint32_t        seqn;                        // sequence number
434
        uint16_t        message;                // message
435
        uint16_t        data_type;                // data type
436
        uint16_t        pkt_len;                // packet length
437
} *cu_head;
438

    
439
        switch(so->so_emu) {
440

    
441
#ifdef EMULATE_TALK
442
         case EMU_TALK:
443
         case EMU_NTALK:
444
                /*
445
                 * Talk emulation. We always change the ctl_addr to get
446
                 * some answers from the daemon. When an ANNOUNCE comes,
447
                 * we send LEAVE_INVITE to the local daemons. Also when a
448
                 * DELETE comes, we send copies to the local daemons.
449
                 */
450
                if (getsockname(so->s, (struct sockaddr *)&addr, &addrlen) < 0)
451
                        return;
452

    
453
#define        IS_OLD        (so->so_emu == EMU_TALK)
454

    
455
#define COPY_MSG(dest, src) { dest->type = src->type; \
456
                              dest->id_num = src->id_num; \
457
                              dest->pid = src->pid; \
458
                              dest->addr = src->addr; \
459
                              dest->ctl_addr = src->ctl_addr; \
460
                              memcpy(&dest->l_name, &src->l_name, NAME_SIZE_OLD); \
461
                              memcpy(&dest->r_name, &src->r_name, NAME_SIZE_OLD); \
462
                               memcpy(&dest->r_tty, &src->r_tty, TTY_SIZE); }
463

    
464
#define OTOSIN(ptr, field) ((struct sockaddr_in *)&ptr->field)
465
/* old_sockaddr to sockaddr_in */
466

    
467

    
468
                if (IS_OLD) {                  /* old talk */
469
                        omsg = mtod(m, CTL_MSG_OLD*);
470
                        nmsg = (CTL_MSG *) buff;
471
                        type = omsg->type;
472
                        OTOSIN(omsg, ctl_addr)->sin_port = addr.sin_port;
473
                        OTOSIN(omsg, ctl_addr)->sin_addr = our_addr;
474
                        strncpy(omsg->l_name, getlogin(), NAME_SIZE_OLD);
475
                } else {                /* new talk */
476
                        omsg = (CTL_MSG_OLD *) buff;
477
                        nmsg = mtod(m, CTL_MSG *);
478
                        type = nmsg->type;
479
                        OTOSIN(nmsg, ctl_addr)->sin_port = addr.sin_port;
480
                        OTOSIN(nmsg, ctl_addr)->sin_addr = our_addr;
481
                        strncpy(nmsg->l_name, getlogin(), NAME_SIZE_OLD);
482
                }
483

    
484
                if (type == LOOK_UP)
485
                        return;                /* for LOOK_UP this is enough */
486

    
487
                if (IS_OLD) {                /* make a copy of the message */
488
                        COPY_MSG(nmsg, omsg);
489
                        nmsg->vers = 1;
490
                        nmsg->answer = 0;
491
                } else
492
                        COPY_MSG(omsg, nmsg);
493

    
494
                /*
495
                 * If if is an ANNOUNCE message, we go through the
496
                 * request table to see if a tcp port has already
497
                 * been redirected for this socket. If not, we solisten()
498
                 * a new socket and add this entry to the table.
499
                 * The port number of the tcp socket and our IP
500
                 * are put to the addr field of the message structures.
501
                 * Then a LEAVE_INVITE is sent to both local daemon
502
                 * ports, 517 and 518. This is why we have two copies
503
                 * of the message, one in old talk and one in new talk
504
                 * format.
505
                 */
506

    
507
                if (type == ANNOUNCE) {
508
                        int s;
509
                        u_short temp_port;
510

    
511
                        for(req = req_tbl; req; req = req->next)
512
                                if (so == req->udp_so)
513
                                        break;          /* found it */
514

    
515
                        if (!req) {        /* no entry for so, create new */
516
                                req = (struct talk_request *)
517
                                        malloc(sizeof(struct talk_request));
518
                                req->udp_so = so;
519
                                req->tcp_so = solisten(0,
520
                                        OTOSIN(omsg, addr)->sin_addr.s_addr,
521
                                        OTOSIN(omsg, addr)->sin_port,
522
                                        SS_FACCEPTONCE);
523
                                req->next = req_tbl;
524
                                req_tbl = req;
525
                        }
526

    
527
                        /* replace port number in addr field */
528
                        addrlen = sizeof(addr);
529
                        getsockname(req->tcp_so->s,
530
                                        (struct sockaddr *) &addr,
531
                                        &addrlen);
532
                        OTOSIN(omsg, addr)->sin_port = addr.sin_port;
533
                        OTOSIN(omsg, addr)->sin_addr = our_addr;
534
                        OTOSIN(nmsg, addr)->sin_port = addr.sin_port;
535
                        OTOSIN(nmsg, addr)->sin_addr = our_addr;
536

    
537
                        /* send LEAVE_INVITEs */
538
                        temp_port = OTOSIN(omsg, ctl_addr)->sin_port;
539
                        OTOSIN(omsg, ctl_addr)->sin_port = 0;
540
                        OTOSIN(nmsg, ctl_addr)->sin_port = 0;
541
                        omsg->type = nmsg->type = LEAVE_INVITE;
542

    
543
                        s = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
544
                        addr.sin_addr = our_addr;
545
                        addr.sin_family = AF_INET;
546
                        addr.sin_port = htons(517);
547
                        sendto(s, (char *)omsg, sizeof(*omsg), 0,
548
                                (struct sockaddr *)&addr, sizeof(addr));
549
                        addr.sin_port = htons(518);
550
                        sendto(s, (char *)nmsg, sizeof(*nmsg), 0,
551
                                (struct sockaddr *) &addr, sizeof(addr));
552
                        closesocket(s) ;
553

    
554
                        omsg->type = nmsg->type = ANNOUNCE;
555
                        OTOSIN(omsg, ctl_addr)->sin_port = temp_port;
556
                        OTOSIN(nmsg, ctl_addr)->sin_port = temp_port;
557
                }
558

    
559
                /*
560
                 * If it is a DELETE message, we send a copy to the
561
                 * local daemons. Then we delete the entry corresponding
562
                 * to our socket from the request table.
563
                 */
564

    
565
                if (type == DELETE) {
566
                        struct talk_request *temp_req, *req_next;
567
                        int s;
568
                        u_short temp_port;
569

    
570
                        temp_port = OTOSIN(omsg, ctl_addr)->sin_port;
571
                        OTOSIN(omsg, ctl_addr)->sin_port = 0;
572
                        OTOSIN(nmsg, ctl_addr)->sin_port = 0;
573

    
574
                        s = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
575
                        addr.sin_addr = our_addr;
576
                        addr.sin_family = AF_INET;
577
                        addr.sin_port = htons(517);
578
                        sendto(s, (char *)omsg, sizeof(*omsg), 0,
579
                                (struct sockaddr *)&addr, sizeof(addr));
580
                        addr.sin_port = htons(518);
581
                        sendto(s, (char *)nmsg, sizeof(*nmsg), 0,
582
                                (struct sockaddr *)&addr, sizeof(addr));
583
                        closesocket(s);
584

    
585
                        OTOSIN(omsg, ctl_addr)->sin_port = temp_port;
586
                        OTOSIN(nmsg, ctl_addr)->sin_port = temp_port;
587

    
588
                        /* delete table entry */
589
                        if (so == req_tbl->udp_so) {
590
                                temp_req = req_tbl;
591
                                req_tbl = req_tbl->next;
592
                                free(temp_req);
593
                        } else {
594
                                temp_req = req_tbl;
595
                                for(req = req_tbl->next; req; req = req_next) {
596
                                        req_next = req->next;
597
                                        if (so == req->udp_so) {
598
                                                temp_req->next = req_next;
599
                                                free(req);
600
                                                break;
601
                                        } else {
602
                                                temp_req = req;
603
                                        }
604
                                }
605
                        }
606
                }
607

    
608
                return;
609
#endif
610

    
611
        case EMU_CUSEEME:
612

    
613
                /*
614
                 * Cu-SeeMe emulation.
615
                 * Hopefully the packet is more that 16 bytes long. We don't
616
                 * do any other tests, just replace the address and port
617
                 * fields.
618
                 */
619
                if (m->m_len >= sizeof (*cu_head)) {
620
                        if (getsockname(so->s, (struct sockaddr *)&addr, &addrlen) < 0)
621
                                return;
622
                        cu_head = mtod(m, struct cu_header *);
623
                        cu_head->s_port = addr.sin_port;
624
                        cu_head->so_addr = our_addr.s_addr;
625
                }
626

    
627
                return;
628
        }
629
}
630

    
631
struct socket *
632
udp_listen(port, laddr, lport, flags)
633
        u_int port;
634
        u_int32_t laddr;
635
        u_int lport;
636
        int flags;
637
{
638
        struct sockaddr_in addr;
639
        struct socket *so;
640
        int addrlen = sizeof(struct sockaddr_in), opt = 1;
641

    
642
        if ((so = socreate()) == NULL) {
643
                free(so);
644
                return NULL;
645
        }
646
        so->s = socket(AF_INET,SOCK_DGRAM,0);
647
        so->so_expire = curtime + SO_EXPIRE;
648
        insque(so,&udb);
649

    
650
        addr.sin_family = AF_INET;
651
        addr.sin_addr.s_addr = INADDR_ANY;
652
        addr.sin_port = port;
653

    
654
        if (bind(so->s,(struct sockaddr *)&addr, addrlen) < 0) {
655
                udp_detach(so);
656
                return NULL;
657
        }
658
        setsockopt(so->s,SOL_SOCKET,SO_REUSEADDR,(char *)&opt,sizeof(int));
659
/*        setsockopt(so->s,SOL_SOCKET,SO_OOBINLINE,(char *)&opt,sizeof(int)); */
660

    
661
        getsockname(so->s,(struct sockaddr *)&addr,&addrlen);
662
        so->so_fport = addr.sin_port;
663
        if (addr.sin_addr.s_addr == 0 || addr.sin_addr.s_addr == loopback_addr.s_addr)
664
           so->so_faddr = alias_addr;
665
        else
666
           so->so_faddr = addr.sin_addr;
667

    
668
        so->so_lport = lport;
669
        so->so_laddr.s_addr = laddr;
670
        if (flags != SS_FACCEPTONCE)
671
           so->so_expire = 0;
672

    
673
        so->so_state = SS_ISFCONNECTED;
674

    
675
        return so;
676
}