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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.
17
 * 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
#ifdef LOG_ENABLED
49
struct udpstat udpstat;
50
#endif
51

    
52
struct socket udb;
53

    
54
static u_int8_t udp_tos(struct socket *so);
55
static void udp_emu(struct socket *so, struct mbuf *m);
56

    
57
/*
58
 * UDP protocol implementation.
59
 * Per RFC 768, August, 1980.
60
 */
61
#ifndef        COMPAT_42
62
#define UDPCKSUM 1
63
#else
64
#define UDPCKSUM 0 /* XXX */
65
#endif
66

    
67
struct        socket *udp_last_so = &udb;
68

    
69
void
70
udp_init()
71
{
72
        udb.so_next = udb.so_prev = &udb;
73
}
74
/* m->m_data  points at ip packet header
75
 * m->m_len   length ip packet
76
 * ip->ip_len length data (IPDU)
77
 */
78
void
79
udp_input(m, iphlen)
80
        register struct mbuf *m;
81
        int iphlen;
82
{
83
        register struct ip *ip;
84
        register struct udphdr *uh;
85
/*        struct mbuf *opts = 0;*/
86
        int len;
87
        struct ip save_ip;
88
        struct socket *so;
89

    
90
        DEBUG_CALL("udp_input");
91
        DEBUG_ARG("m = %lx", (long)m);
92
        DEBUG_ARG("iphlen = %d", iphlen);
93

    
94
        STAT(udpstat.udps_ipackets++);
95

    
96
        /*
97
         * Strip IP options, if any; should skip this,
98
         * make available to user, and use on returned packets,
99
         * but we don't yet have a way to check the checksum
100
         * with options still present.
101
         */
102
        if(iphlen > sizeof(struct ip)) {
103
                ip_stripoptions(m, (struct mbuf *)0);
104
                iphlen = sizeof(struct ip);
105
        }
106

    
107
        /*
108
         * Get IP and UDP header together in first mbuf.
109
         */
110
        ip = mtod(m, struct ip *);
111
        uh = (struct udphdr *)((caddr_t)ip + iphlen);
112

    
113
        /*
114
         * Make mbuf data length reflect UDP length.
115
         * If not enough data to reflect UDP length, drop.
116
         */
117
        len = ntohs((u_int16_t)uh->uh_ulen);
118

    
119
        if (ip->ip_len != len) {
120
                if (len > ip->ip_len) {
121
                        STAT(udpstat.udps_badlen++);
122
                        goto bad;
123
                }
124
                m_adj(m, len - ip->ip_len);
125
                ip->ip_len = len;
126
        }
127

    
128
        /*
129
         * Save a copy of the IP header in case we want restore it
130
         * for sending an ICMP error message in response.
131
         */
132
        save_ip = *ip;
133
        save_ip.ip_len+= iphlen;         /* tcp_input subtracts this */
134

    
135
        /*
136
         * Checksum extended UDP header and data.
137
         */
138
        if (UDPCKSUM && uh->uh_sum) {
139
          ((struct ipovly *)ip)->ih_next = 0;
140
          ((struct ipovly *)ip)->ih_prev = 0;
141
          ((struct ipovly *)ip)->ih_x1 = 0;
142
          ((struct ipovly *)ip)->ih_len = uh->uh_ulen;
143
          /* keep uh_sum for ICMP reply
144
           * uh->uh_sum = cksum(m, len + sizeof (struct ip));
145
           * if (uh->uh_sum) {
146
           */
147
          if(cksum(m, len + sizeof(struct ip))) {
148
            STAT(udpstat.udps_badsum++);
149
            goto bad;
150
          }
151
        }
152

    
153
        /*
154
         *  handle DHCP/BOOTP
155
         */
156
        if (ntohs(uh->uh_dport) == BOOTP_SERVER) {
157
            bootp_input(m);
158
            goto bad;
159
        }
160

    
161
        /*
162
         *  handle TFTP
163
         */
164
        if (ntohs(uh->uh_dport) == TFTP_SERVER) {
165
            tftp_input(m);
166
            goto bad;
167
        }
168

    
169
        /*
170
         * Locate pcb for datagram.
171
         */
172
        so = udp_last_so;
173
        if (so->so_lport != uh->uh_sport ||
174
            so->so_laddr.s_addr != ip->ip_src.s_addr) {
175
                struct socket *tmp;
176

    
177
                for (tmp = udb.so_next; tmp != &udb; tmp = tmp->so_next) {
178
                        if (tmp->so_lport == uh->uh_sport &&
179
                            tmp->so_laddr.s_addr == ip->ip_src.s_addr) {
180
                                tmp->so_faddr.s_addr = ip->ip_dst.s_addr;
181
                                tmp->so_fport = uh->uh_dport;
182
                                so = tmp;
183
                                break;
184
                        }
185
                }
186
                if (tmp == &udb) {
187
                  so = NULL;
188
                } else {
189
                  STAT(udpstat.udpps_pcbcachemiss++);
190
                  udp_last_so = so;
191
                }
192
        }
193

    
194
        if (so == NULL) {
195
          /*
196
           * If there's no socket for this packet,
197
           * create one
198
           */
199
          if ((so = socreate()) == NULL) goto bad;
200
          if(udp_attach(so) == -1) {
201
            DEBUG_MISC((dfd," udp_attach errno = %d-%s\n",
202
                        errno,strerror(errno)));
203
            sofree(so);
204
            goto bad;
205
          }
206

    
207
          /*
208
           * Setup fields
209
           */
210
          /* udp_last_so = so; */
211
          so->so_laddr = ip->ip_src;
212
          so->so_lport = uh->uh_sport;
213

    
214
          if ((so->so_iptos = udp_tos(so)) == 0)
215
            so->so_iptos = ip->ip_tos;
216

    
217
          /*
218
           * XXXXX Here, check if it's in udpexec_list,
219
           * and if it is, do the fork_exec() etc.
220
           */
221
        }
222

    
223
        so->so_faddr = ip->ip_dst; /* XXX */
224
        so->so_fport = uh->uh_dport; /* XXX */
225

    
226
        iphlen += sizeof(struct udphdr);
227
        m->m_len -= iphlen;
228
        m->m_data += iphlen;
229

    
230
        /*
231
         * Now we sendto() the packet.
232
         */
233
        if (so->so_emu)
234
           udp_emu(so, m);
235

    
236
        if(sosendto(so,m) == -1) {
237
          m->m_len += iphlen;
238
          m->m_data -= iphlen;
239
          *ip=save_ip;
240
          DEBUG_MISC((dfd,"udp tx errno = %d-%s\n",errno,strerror(errno)));
241
          icmp_error(m, ICMP_UNREACH,ICMP_UNREACH_NET, 0,strerror(errno));
242
        }
243

    
244
        m_free(so->so_m);   /* used for ICMP if error on sorecvfrom */
245

    
246
        /* restore the orig mbuf packet */
247
        m->m_len += iphlen;
248
        m->m_data -= iphlen;
249
        *ip=save_ip;
250
        so->so_m=m;         /* ICMP backup */
251

    
252
        return;
253
bad:
254
        m_freem(m);
255
        /* if (opts) m_freem(opts); */
256
        return;
257
}
258

    
259
int udp_output2(struct socket *so, struct mbuf *m,
260
                struct sockaddr_in *saddr, struct sockaddr_in *daddr,
261
                int iptos)
262
{
263
        register struct udpiphdr *ui;
264
        int error = 0;
265

    
266
        DEBUG_CALL("udp_output");
267
        DEBUG_ARG("so = %lx", (long)so);
268
        DEBUG_ARG("m = %lx", (long)m);
269
        DEBUG_ARG("saddr = %lx", (long)saddr->sin_addr.s_addr);
270
        DEBUG_ARG("daddr = %lx", (long)daddr->sin_addr.s_addr);
271

    
272
        /*
273
         * Adjust for header
274
         */
275
        m->m_data -= sizeof(struct udpiphdr);
276
        m->m_len += sizeof(struct udpiphdr);
277

    
278
        /*
279
         * Fill in mbuf with extended UDP header
280
         * and addresses and length put into network format.
281
         */
282
        ui = mtod(m, struct udpiphdr *);
283
        ui->ui_next = ui->ui_prev = 0;
284
        ui->ui_x1 = 0;
285
        ui->ui_pr = IPPROTO_UDP;
286
        ui->ui_len = htons(m->m_len - sizeof(struct ip)); /* + sizeof (struct udphdr)); */
287
        /* XXXXX Check for from-one-location sockets, or from-any-location sockets */
288
        ui->ui_src = saddr->sin_addr;
289
        ui->ui_dst = daddr->sin_addr;
290
        ui->ui_sport = saddr->sin_port;
291
        ui->ui_dport = daddr->sin_port;
292
        ui->ui_ulen = ui->ui_len;
293

    
294
        /*
295
         * Stuff checksum and output datagram.
296
         */
297
        ui->ui_sum = 0;
298
        if (UDPCKSUM) {
299
            if ((ui->ui_sum = cksum(m, /* sizeof (struct udpiphdr) + */ m->m_len)) == 0)
300
                ui->ui_sum = 0xffff;
301
        }
302
        ((struct ip *)ui)->ip_len = m->m_len;
303

    
304
        ((struct ip *)ui)->ip_ttl = IPDEFTTL;
305
        ((struct ip *)ui)->ip_tos = iptos;
306

    
307
        STAT(udpstat.udps_opackets++);
308

    
309
        error = ip_output(so, m);
310

    
311
        return (error);
312
}
313

    
314
int udp_output(struct socket *so, struct mbuf *m,
315
               struct sockaddr_in *addr)
316

    
317
{
318
    struct sockaddr_in saddr, daddr;
319

    
320
    saddr = *addr;
321
    if ((so->so_faddr.s_addr & htonl(0xffffff00)) == special_addr.s_addr) {
322
        if ((so->so_faddr.s_addr & htonl(0x000000ff)) == htonl(0xff))
323
            saddr.sin_addr.s_addr = alias_addr.s_addr;
324
        else if (addr->sin_addr.s_addr == loopback_addr.s_addr ||
325
                 (ntohl(so->so_faddr.s_addr) & 0xff) != CTL_ALIAS)
326
            saddr.sin_addr.s_addr = so->so_faddr.s_addr;
327
    }
328
    daddr.sin_addr = so->so_laddr;
329
    daddr.sin_port = so->so_lport;
330

    
331
    return udp_output2(so, m, &saddr, &daddr, so->so_iptos);
332
}
333

    
334
int
335
udp_attach(so)
336
     struct socket *so;
337
{
338
  struct sockaddr_in addr;
339

    
340
  if((so->s = socket(AF_INET,SOCK_DGRAM,0)) != -1) {
341
    /*
342
     * Here, we bind() the socket.  Although not really needed
343
     * (sendto() on an unbound socket will bind it), it's done
344
     * here so that emulation of ytalk etc. don't have to do it
345
     */
346
    addr.sin_family = AF_INET;
347
    addr.sin_port = 0;
348
    addr.sin_addr.s_addr = INADDR_ANY;
349
    if(bind(so->s, (struct sockaddr *)&addr, sizeof(addr))<0) {
350
      int lasterrno=errno;
351
      closesocket(so->s);
352
      so->s=-1;
353
#ifdef _WIN32
354
      WSASetLastError(lasterrno);
355
#else
356
      errno=lasterrno;
357
#endif
358
    } else {
359
      /* success, insert in queue */
360
      so->so_expire = curtime + SO_EXPIRE;
361
      insque(so,&udb);
362
    }
363
  }
364
  return(so->s);
365
}
366

    
367
void
368
udp_detach(so)
369
        struct socket *so;
370
{
371
        closesocket(so->s);
372
        /* if (so->so_m) m_free(so->so_m);    done by sofree */
373

    
374
        sofree(so);
375
}
376

    
377
static const struct tos_t udptos[] = {
378
        {0, 53, IPTOS_LOWDELAY, 0},                        /* DNS */
379
        {517, 517, IPTOS_LOWDELAY, EMU_TALK},        /* talk */
380
        {518, 518, IPTOS_LOWDELAY, EMU_NTALK},        /* ntalk */
381
        {0, 7648, IPTOS_LOWDELAY, EMU_CUSEEME},        /* Cu-Seeme */
382
        {0, 0, 0, 0}
383
};
384

    
385
static u_int8_t
386
udp_tos(struct socket *so)
387
{
388
        int i = 0;
389

    
390
        while(udptos[i].tos) {
391
                if ((udptos[i].fport && ntohs(so->so_fport) == udptos[i].fport) ||
392
                    (udptos[i].lport && ntohs(so->so_lport) == udptos[i].lport)) {
393
                            so->so_emu = udptos[i].emu;
394
                        return udptos[i].tos;
395
                }
396
                i++;
397
        }
398

    
399
        return 0;
400
}
401

    
402
#ifdef EMULATE_TALK
403
#include "talkd.h"
404
#endif
405

    
406
/*
407
 * Here, talk/ytalk/ntalk requests must be emulated
408
 */
409
static void
410
udp_emu(struct socket *so, struct mbuf *m)
411
{
412
        struct sockaddr_in addr;
413
        socklen_t addrlen = sizeof(addr);
414
#ifdef EMULATE_TALK
415
        CTL_MSG_OLD *omsg;
416
        CTL_MSG *nmsg;
417
        char buff[sizeof(CTL_MSG)];
418
        u_char type;
419

    
420
struct talk_request {
421
        struct talk_request *next;
422
        struct socket *udp_so;
423
        struct socket *tcp_so;
424
} *req;
425

    
426
        static struct talk_request *req_tbl = 0;
427

    
428
#endif
429

    
430
struct cu_header {
431
        uint16_t        d_family;                // destination family
432
        uint16_t        d_port;                        // destination port
433
        uint32_t        d_addr;                        // destination address
434
        uint16_t        s_family;                // source family
435
        uint16_t        s_port;                        // source port
436
        uint32_t        so_addr;                // source address
437
        uint32_t        seqn;                        // sequence number
438
        uint16_t        message;                // message
439
        uint16_t        data_type;                // data type
440
        uint16_t        pkt_len;                // packet length
441
} *cu_head;
442

    
443
        switch(so->so_emu) {
444

    
445
#ifdef EMULATE_TALK
446
         case EMU_TALK:
447
         case EMU_NTALK:
448
                /*
449
                 * Talk emulation. We always change the ctl_addr to get
450
                 * some answers from the daemon. When an ANNOUNCE comes,
451
                 * we send LEAVE_INVITE to the local daemons. Also when a
452
                 * DELETE comes, we send copies to the local daemons.
453
                 */
454
                if (getsockname(so->s, (struct sockaddr *)&addr, &addrlen) < 0)
455
                        return;
456

    
457
#define        IS_OLD        (so->so_emu == EMU_TALK)
458

    
459
#define COPY_MSG(dest, src) { dest->type = src->type; \
460
                              dest->id_num = src->id_num; \
461
                              dest->pid = src->pid; \
462
                              dest->addr = src->addr; \
463
                              dest->ctl_addr = src->ctl_addr; \
464
                              memcpy(&dest->l_name, &src->l_name, NAME_SIZE_OLD); \
465
                              memcpy(&dest->r_name, &src->r_name, NAME_SIZE_OLD); \
466
                               memcpy(&dest->r_tty, &src->r_tty, TTY_SIZE); }
467

    
468
#define OTOSIN(ptr, field) ((struct sockaddr_in *)&ptr->field)
469
/* old_sockaddr to sockaddr_in */
470

    
471

    
472
                if (IS_OLD) {                  /* old talk */
473
                        omsg = mtod(m, CTL_MSG_OLD*);
474
                        nmsg = (CTL_MSG *) buff;
475
                        type = omsg->type;
476
                        OTOSIN(omsg, ctl_addr)->sin_port = addr.sin_port;
477
                        OTOSIN(omsg, ctl_addr)->sin_addr = our_addr;
478
                        strncpy(omsg->l_name, getlogin(), NAME_SIZE_OLD);
479
                } else {                /* new talk */
480
                        omsg = (CTL_MSG_OLD *) buff;
481
                        nmsg = mtod(m, CTL_MSG *);
482
                        type = nmsg->type;
483
                        OTOSIN(nmsg, ctl_addr)->sin_port = addr.sin_port;
484
                        OTOSIN(nmsg, ctl_addr)->sin_addr = our_addr;
485
                        strncpy(nmsg->l_name, getlogin(), NAME_SIZE_OLD);
486
                }
487

    
488
                if (type == LOOK_UP)
489
                        return;                /* for LOOK_UP this is enough */
490

    
491
                if (IS_OLD) {                /* make a copy of the message */
492
                        COPY_MSG(nmsg, omsg);
493
                        nmsg->vers = 1;
494
                        nmsg->answer = 0;
495
                } else
496
                        COPY_MSG(omsg, nmsg);
497

    
498
                /*
499
                 * If if is an ANNOUNCE message, we go through the
500
                 * request table to see if a tcp port has already
501
                 * been redirected for this socket. If not, we solisten()
502
                 * a new socket and add this entry to the table.
503
                 * The port number of the tcp socket and our IP
504
                 * are put to the addr field of the message structures.
505
                 * Then a LEAVE_INVITE is sent to both local daemon
506
                 * ports, 517 and 518. This is why we have two copies
507
                 * of the message, one in old talk and one in new talk
508
                 * format.
509
                 */
510

    
511
                if (type == ANNOUNCE) {
512
                        int s;
513
                        u_short temp_port;
514

    
515
                        for(req = req_tbl; req; req = req->next)
516
                                if (so == req->udp_so)
517
                                        break;          /* found it */
518

    
519
                        if (!req) {        /* no entry for so, create new */
520
                                req = (struct talk_request *)
521
                                        malloc(sizeof(struct talk_request));
522
                                req->udp_so = so;
523
                                req->tcp_so = solisten(0,
524
                                        OTOSIN(omsg, addr)->sin_addr.s_addr,
525
                                        OTOSIN(omsg, addr)->sin_port,
526
                                        SS_FACCEPTONCE);
527
                                req->next = req_tbl;
528
                                req_tbl = req;
529
                        }
530

    
531
                        /* replace port number in addr field */
532
                        addrlen = sizeof(addr);
533
                        getsockname(req->tcp_so->s,
534
                                        (struct sockaddr *) &addr,
535
                                        &addrlen);
536
                        OTOSIN(omsg, addr)->sin_port = addr.sin_port;
537
                        OTOSIN(omsg, addr)->sin_addr = our_addr;
538
                        OTOSIN(nmsg, addr)->sin_port = addr.sin_port;
539
                        OTOSIN(nmsg, addr)->sin_addr = our_addr;
540

    
541
                        /* send LEAVE_INVITEs */
542
                        temp_port = OTOSIN(omsg, ctl_addr)->sin_port;
543
                        OTOSIN(omsg, ctl_addr)->sin_port = 0;
544
                        OTOSIN(nmsg, ctl_addr)->sin_port = 0;
545
                        omsg->type = nmsg->type = LEAVE_INVITE;
546

    
547
                        s = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
548
                        addr.sin_addr = our_addr;
549
                        addr.sin_family = AF_INET;
550
                        addr.sin_port = htons(517);
551
                        sendto(s, (char *)omsg, sizeof(*omsg), 0,
552
                                (struct sockaddr *)&addr, sizeof(addr));
553
                        addr.sin_port = htons(518);
554
                        sendto(s, (char *)nmsg, sizeof(*nmsg), 0,
555
                                (struct sockaddr *) &addr, sizeof(addr));
556
                        closesocket(s) ;
557

    
558
                        omsg->type = nmsg->type = ANNOUNCE;
559
                        OTOSIN(omsg, ctl_addr)->sin_port = temp_port;
560
                        OTOSIN(nmsg, ctl_addr)->sin_port = temp_port;
561
                }
562

    
563
                /*
564
                 * If it is a DELETE message, we send a copy to the
565
                 * local daemons. Then we delete the entry corresponding
566
                 * to our socket from the request table.
567
                 */
568

    
569
                if (type == DELETE) {
570
                        struct talk_request *temp_req, *req_next;
571
                        int s;
572
                        u_short temp_port;
573

    
574
                        temp_port = OTOSIN(omsg, ctl_addr)->sin_port;
575
                        OTOSIN(omsg, ctl_addr)->sin_port = 0;
576
                        OTOSIN(nmsg, ctl_addr)->sin_port = 0;
577

    
578
                        s = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
579
                        addr.sin_addr = our_addr;
580
                        addr.sin_family = AF_INET;
581
                        addr.sin_port = htons(517);
582
                        sendto(s, (char *)omsg, sizeof(*omsg), 0,
583
                                (struct sockaddr *)&addr, sizeof(addr));
584
                        addr.sin_port = htons(518);
585
                        sendto(s, (char *)nmsg, sizeof(*nmsg), 0,
586
                                (struct sockaddr *)&addr, sizeof(addr));
587
                        closesocket(s);
588

    
589
                        OTOSIN(omsg, ctl_addr)->sin_port = temp_port;
590
                        OTOSIN(nmsg, ctl_addr)->sin_port = temp_port;
591

    
592
                        /* delete table entry */
593
                        if (so == req_tbl->udp_so) {
594
                                temp_req = req_tbl;
595
                                req_tbl = req_tbl->next;
596
                                free(temp_req);
597
                        } else {
598
                                temp_req = req_tbl;
599
                                for(req = req_tbl->next; req; req = req_next) {
600
                                        req_next = req->next;
601
                                        if (so == req->udp_so) {
602
                                                temp_req->next = req_next;
603
                                                free(req);
604
                                                break;
605
                                        } else {
606
                                                temp_req = req;
607
                                        }
608
                                }
609
                        }
610
                }
611

    
612
                return;
613
#endif
614

    
615
        case EMU_CUSEEME:
616

    
617
                /*
618
                 * Cu-SeeMe emulation.
619
                 * Hopefully the packet is more that 16 bytes long. We don't
620
                 * do any other tests, just replace the address and port
621
                 * fields.
622
                 */
623
                if (m->m_len >= sizeof (*cu_head)) {
624
                        if (getsockname(so->s, (struct sockaddr *)&addr, &addrlen) < 0)
625
                                return;
626
                        cu_head = mtod(m, struct cu_header *);
627
                        cu_head->s_port = addr.sin_port;
628
                        cu_head->so_addr = our_addr.s_addr;
629
                }
630

    
631
                return;
632
        }
633
}
634

    
635
struct socket *
636
udp_listen(port, laddr, lport, flags)
637
        u_int port;
638
        u_int32_t laddr;
639
        u_int lport;
640
        int flags;
641
{
642
        struct sockaddr_in addr;
643
        struct socket *so;
644
        socklen_t addrlen = sizeof(struct sockaddr_in), opt = 1;
645

    
646
        if ((so = socreate()) == NULL) {
647
                free(so);
648
                return NULL;
649
        }
650
        so->s = socket(AF_INET,SOCK_DGRAM,0);
651
        so->so_expire = curtime + SO_EXPIRE;
652
        insque(so,&udb);
653

    
654
        addr.sin_family = AF_INET;
655
        addr.sin_addr.s_addr = INADDR_ANY;
656
        addr.sin_port = port;
657

    
658
        if (bind(so->s,(struct sockaddr *)&addr, addrlen) < 0) {
659
                udp_detach(so);
660
                return NULL;
661
        }
662
        setsockopt(so->s,SOL_SOCKET,SO_REUSEADDR,(char *)&opt,sizeof(int));
663
/*        setsockopt(so->s,SOL_SOCKET,SO_OOBINLINE,(char *)&opt,sizeof(int)); */
664

    
665
        getsockname(so->s,(struct sockaddr *)&addr,&addrlen);
666
        so->so_fport = addr.sin_port;
667
        if (addr.sin_addr.s_addr == 0 || addr.sin_addr.s_addr == loopback_addr.s_addr)
668
           so->so_faddr = alias_addr;
669
        else
670
           so->so_faddr = addr.sin_addr;
671

    
672
        so->so_lport = lport;
673
        so->so_laddr.s_addr = laddr;
674
        if (flags != SS_FACCEPTONCE)
675
           so->so_expire = 0;
676

    
677
        so->so_state = SS_ISFCONNECTED;
678

    
679
        return so;
680
}