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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
16
 *        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
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
          so->so_faddr = ip->ip_dst; /* XXX */
209
          so->so_fport = uh->uh_dport; /* XXX */
210
          
211
          if ((so->so_iptos = udp_tos(so)) == 0)
212
            so->so_iptos = ip->ip_tos;
213
          
214
          /*
215
           * XXXXX Here, check if it's in udpexec_list,
216
           * and if it is, do the fork_exec() etc.
217
           */
218
        }
219

    
220
        iphlen += sizeof(struct udphdr);
221
        m->m_len -= iphlen;
222
        m->m_data += iphlen;
223

    
224
        /*
225
         * Now we sendto() the packet.
226
         */
227
        if (so->so_emu)
228
           udp_emu(so, m);
229

    
230
        if(sosendto(so,m) == -1) {
231
          m->m_len += iphlen;
232
          m->m_data -= iphlen;
233
          *ip=save_ip;
234
          DEBUG_MISC((dfd,"udp tx errno = %d-%s\n",errno,strerror(errno)));
235
          icmp_error(m, ICMP_UNREACH,ICMP_UNREACH_NET, 0,strerror(errno));  
236
        }
237

    
238
        m_free(so->so_m);   /* used for ICMP if error on sorecvfrom */
239

    
240
        /* restore the orig mbuf packet */
241
        m->m_len += iphlen;
242
        m->m_data -= iphlen;
243
        *ip=save_ip;
244
        so->so_m=m;         /* ICMP backup */
245

    
246
        return;
247
bad:
248
        m_freem(m);
249
        /* if (opts) m_freem(opts); */
250
        return;
251
}
252

    
253
int udp_output2(struct socket *so, struct mbuf *m, 
254
                struct sockaddr_in *saddr, struct sockaddr_in *daddr,
255
                int iptos)
256
{
257
        register struct udpiphdr *ui;
258
        int error = 0;
259

    
260
        DEBUG_CALL("udp_output");
261
        DEBUG_ARG("so = %lx", (long)so);
262
        DEBUG_ARG("m = %lx", (long)m);
263
        DEBUG_ARG("saddr = %lx", (long)saddr->sin_addr.s_addr);
264
        DEBUG_ARG("daddr = %lx", (long)daddr->sin_addr.s_addr);
265

    
266
        /*
267
         * Adjust for header
268
         */
269
        m->m_data -= sizeof(struct udpiphdr);
270
        m->m_len += sizeof(struct udpiphdr);
271
        
272
        /*
273
         * Fill in mbuf with extended UDP header
274
         * and addresses and length put into network format.
275
         */
276
        ui = mtod(m, struct udpiphdr *);
277
        ui->ui_next = ui->ui_prev = 0;
278
        ui->ui_x1 = 0;
279
        ui->ui_pr = IPPROTO_UDP;
280
        ui->ui_len = htons(m->m_len - sizeof(struct ip)); /* + sizeof (struct udphdr)); */
281
        /* XXXXX Check for from-one-location sockets, or from-any-location sockets */
282
        ui->ui_src = saddr->sin_addr;
283
        ui->ui_dst = daddr->sin_addr;
284
        ui->ui_sport = saddr->sin_port;
285
        ui->ui_dport = daddr->sin_port;
286
        ui->ui_ulen = ui->ui_len;
287

    
288
        /*
289
         * Stuff checksum and output datagram.
290
         */
291
        ui->ui_sum = 0;
292
        if (udpcksum) {
293
            if ((ui->ui_sum = cksum(m, /* sizeof (struct udpiphdr) + */ m->m_len)) == 0)
294
                ui->ui_sum = 0xffff;
295
        }
296
        ((struct ip *)ui)->ip_len = m->m_len;
297

    
298
        ((struct ip *)ui)->ip_ttl = ip_defttl;
299
        ((struct ip *)ui)->ip_tos = iptos;
300
        
301
        udpstat.udps_opackets++;
302
        
303
        error = ip_output(so, m);
304
        
305
        return (error);
306
}
307

    
308
int udp_output(struct socket *so, struct mbuf *m, 
309
               struct sockaddr_in *addr)
310

    
311
{
312
    struct sockaddr_in saddr, daddr;
313

    
314
    saddr = *addr;
315
    if ((so->so_faddr.s_addr & htonl(0xffffff00)) == special_addr.s_addr)
316
        saddr.sin_addr.s_addr = so->so_faddr.s_addr;
317
    daddr.sin_addr = so->so_laddr;
318
    daddr.sin_port = so->so_lport;
319
    
320
    return udp_output2(so, m, &saddr, &daddr, so->so_iptos);
321
}
322

    
323
int
324
udp_attach(so)
325
     struct socket *so;
326
{
327
  struct sockaddr_in addr;
328
        
329
  if((so->s = socket(AF_INET,SOCK_DGRAM,0)) != -1) {
330
    /*
331
     * Here, we bind() the socket.  Although not really needed
332
     * (sendto() on an unbound socket will bind it), it's done
333
     * here so that emulation of ytalk etc. don't have to do it
334
     */
335
    addr.sin_family = AF_INET;
336
    addr.sin_port = 0;
337
    addr.sin_addr.s_addr = INADDR_ANY;
338
    if(bind(so->s, (struct sockaddr *)&addr, sizeof(addr))<0) {
339
      int lasterrno=errno;
340
      closesocket(so->s);
341
      so->s=-1;
342
#ifdef _WIN32
343
      WSASetLastError(lasterrno);
344
#else
345
      errno=lasterrno;
346
#endif
347
    } else {
348
      /* success, insert in queue */
349
      so->so_expire = curtime + SO_EXPIRE;
350
      insque(so,&udb);
351
    }
352
  }
353
  return(so->s);
354
}
355

    
356
void
357
udp_detach(so)
358
        struct socket *so;
359
{
360
        closesocket(so->s);
361
        /* if (so->so_m) m_free(so->so_m);    done by sofree */
362

    
363
        sofree(so);
364
}
365

    
366
struct tos_t udptos[] = {
367
        {0, 53, IPTOS_LOWDELAY, 0},                        /* DNS */
368
        {517, 517, IPTOS_LOWDELAY, EMU_TALK},        /* talk */
369
        {518, 518, IPTOS_LOWDELAY, EMU_NTALK},        /* ntalk */
370
        {0, 7648, IPTOS_LOWDELAY, EMU_CUSEEME},        /* Cu-Seeme */
371
        {0, 0, 0, 0}
372
};
373

    
374
u_int8_t
375
udp_tos(so)
376
        struct socket *so;
377
{
378
        int i = 0;
379
        
380
        while(udptos[i].tos) {
381
                if ((udptos[i].fport && ntohs(so->so_fport) == udptos[i].fport) ||
382
                    (udptos[i].lport && ntohs(so->so_lport) == udptos[i].lport)) {
383
                            so->so_emu = udptos[i].emu;
384
                        return udptos[i].tos;
385
                }
386
                i++;
387
        }
388
        
389
        return 0;
390
}
391

    
392
#ifdef EMULATE_TALK
393
#include "talkd.h"
394
#endif
395

    
396
/*
397
 * Here, talk/ytalk/ntalk requests must be emulated
398
 */
399
void
400
udp_emu(so, m)
401
        struct socket *so;
402
        struct mbuf *m;
403
{
404
        struct sockaddr_in addr;
405
        int addrlen = sizeof(addr);
406
#ifdef EMULATE_TALK
407
        CTL_MSG_OLD *omsg;
408
        CTL_MSG *nmsg;
409
        char buff[sizeof(CTL_MSG)];
410
        u_char type;
411
        
412
struct talk_request {
413
        struct talk_request *next;
414
        struct socket *udp_so;
415
        struct socket *tcp_so;
416
} *req;
417
        
418
        static struct talk_request *req_tbl = 0;        
419
        
420
#endif
421
        
422
struct cu_header {
423
        uint16_t        d_family;                // destination family
424
        uint16_t        d_port;                        // destination port
425
        uint32_t        d_addr;                        // destination address
426
        uint16_t        s_family;                // source family
427
        uint16_t        s_port;                        // source port
428
        uint32_t        so_addr;                // source address
429
        uint32_t        seqn;                        // sequence number
430
        uint16_t        message;                // message
431
        uint16_t        data_type;                // data type
432
        uint16_t        pkt_len;                // packet length
433
} *cu_head;
434

    
435
        switch(so->so_emu) {
436

    
437
#ifdef EMULATE_TALK
438
         case EMU_TALK:
439
         case EMU_NTALK:
440
                /*
441
                 * Talk emulation. We always change the ctl_addr to get
442
                 * some answers from the daemon. When an ANNOUNCE comes,
443
                 * we send LEAVE_INVITE to the local daemons. Also when a
444
                 * DELETE comes, we send copies to the local daemons.
445
                 */
446
                if (getsockname(so->s, (struct sockaddr *)&addr, &addrlen) < 0)
447
                        return;
448
                
449
#define        IS_OLD        (so->so_emu == EMU_TALK)
450

    
451
#define COPY_MSG(dest, src) { dest->type = src->type; \
452
                              dest->id_num = src->id_num; \
453
                              dest->pid = src->pid; \
454
                              dest->addr = src->addr; \
455
                              dest->ctl_addr = src->ctl_addr; \
456
                              memcpy(&dest->l_name, &src->l_name, NAME_SIZE_OLD); \
457
                              memcpy(&dest->r_name, &src->r_name, NAME_SIZE_OLD); \
458
                               memcpy(&dest->r_tty, &src->r_tty, TTY_SIZE); }
459

    
460
#define OTOSIN(ptr, field) ((struct sockaddr_in *)&ptr->field)
461
/* old_sockaddr to sockaddr_in */
462

    
463

    
464
                if (IS_OLD) {                  /* old talk */
465
                        omsg = mtod(m, CTL_MSG_OLD*);
466
                        nmsg = (CTL_MSG *) buff;
467
                        type = omsg->type;
468
                        OTOSIN(omsg, ctl_addr)->sin_port = addr.sin_port;
469
                        OTOSIN(omsg, ctl_addr)->sin_addr = our_addr;
470
                        strncpy(omsg->l_name, getlogin(), NAME_SIZE_OLD);
471
                } else {                /* new talk */        
472
                        omsg = (CTL_MSG_OLD *) buff;
473
                        nmsg = mtod(m, CTL_MSG *);
474
                        type = nmsg->type;
475
                        OTOSIN(nmsg, ctl_addr)->sin_port = addr.sin_port;
476
                        OTOSIN(nmsg, ctl_addr)->sin_addr = our_addr;
477
                        strncpy(nmsg->l_name, getlogin(), NAME_SIZE_OLD);
478
                }
479
                
480
                if (type == LOOK_UP) 
481
                        return;                /* for LOOK_UP this is enough */
482
                        
483
                if (IS_OLD) {                /* make a copy of the message */
484
                        COPY_MSG(nmsg, omsg);
485
                        nmsg->vers = 1;
486
                        nmsg->answer = 0;
487
                } else
488
                        COPY_MSG(omsg, nmsg);
489

    
490
                /*
491
                 * If if is an ANNOUNCE message, we go through the
492
                 * request table to see if a tcp port has already
493
                 * been redirected for this socket. If not, we solisten()
494
                 * a new socket and add this entry to the table.
495
                 * The port number of the tcp socket and our IP
496
                 * are put to the addr field of the message structures.
497
                 * Then a LEAVE_INVITE is sent to both local daemon
498
                 * ports, 517 and 518. This is why we have two copies
499
                 * of the message, one in old talk and one in new talk
500
                 * format.
501
                 */ 
502

    
503
                if (type == ANNOUNCE) {
504
                        int s;
505
                        u_short temp_port;
506
                        
507
                        for(req = req_tbl; req; req = req->next)
508
                                if (so == req->udp_so)
509
                                        break;          /* found it */
510
                                        
511
                        if (!req) {        /* no entry for so, create new */
512
                                req = (struct talk_request *)
513
                                        malloc(sizeof(struct talk_request));
514
                                req->udp_so = so;
515
                                req->tcp_so = solisten(0,                
516
                                        OTOSIN(omsg, addr)->sin_addr.s_addr,        
517
                                        OTOSIN(omsg, addr)->sin_port,
518
                                        SS_FACCEPTONCE);
519
                                req->next = req_tbl;
520
                                req_tbl = req;
521
                        }                        
522
                        
523
                        /* replace port number in addr field */
524
                        addrlen = sizeof(addr);
525
                        getsockname(req->tcp_so->s, 
526
                                        (struct sockaddr *) &addr,
527
                                        &addrlen);                
528
                        OTOSIN(omsg, addr)->sin_port = addr.sin_port;
529
                        OTOSIN(omsg, addr)->sin_addr = our_addr;
530
                        OTOSIN(nmsg, addr)->sin_port = addr.sin_port;
531
                        OTOSIN(nmsg, addr)->sin_addr = our_addr;                
532
                        
533
                        /* send LEAVE_INVITEs */
534
                        temp_port = OTOSIN(omsg, ctl_addr)->sin_port;
535
                        OTOSIN(omsg, ctl_addr)->sin_port = 0;
536
                        OTOSIN(nmsg, ctl_addr)->sin_port = 0;
537
                        omsg->type = nmsg->type = LEAVE_INVITE;                        
538
                        
539
                        s = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
540
                        addr.sin_addr = our_addr;
541
                        addr.sin_family = AF_INET;
542
                        addr.sin_port = htons(517);
543
                        sendto(s, (char *)omsg, sizeof(*omsg), 0, 
544
                                (struct sockaddr *)&addr, sizeof(addr));
545
                        addr.sin_port = htons(518);
546
                        sendto(s, (char *)nmsg, sizeof(*nmsg), 0,
547
                                (struct sockaddr *) &addr, sizeof(addr));
548
                        closesocket(s) ;
549

    
550
                        omsg->type = nmsg->type = ANNOUNCE; 
551
                        OTOSIN(omsg, ctl_addr)->sin_port = temp_port;
552
                        OTOSIN(nmsg, ctl_addr)->sin_port = temp_port;
553
                }
554
                
555
                /*        
556
                 * If it is a DELETE message, we send a copy to the
557
                 * local daemons. Then we delete the entry corresponding
558
                 * to our socket from the request table.
559
                 */
560
                
561
                if (type == DELETE) {
562
                        struct talk_request *temp_req, *req_next;
563
                        int s;
564
                        u_short temp_port;
565
                        
566
                        temp_port = OTOSIN(omsg, ctl_addr)->sin_port;
567
                        OTOSIN(omsg, ctl_addr)->sin_port = 0;
568
                        OTOSIN(nmsg, ctl_addr)->sin_port = 0;
569
                        
570
                        s = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
571
                        addr.sin_addr = our_addr;
572
                        addr.sin_family = AF_INET;
573
                        addr.sin_port = htons(517);
574
                        sendto(s, (char *)omsg, sizeof(*omsg), 0,
575
                                (struct sockaddr *)&addr, sizeof(addr));
576
                        addr.sin_port = htons(518);
577
                        sendto(s, (char *)nmsg, sizeof(*nmsg), 0,
578
                                (struct sockaddr *)&addr, sizeof(addr));
579
                        closesocket(s);
580
                        
581
                        OTOSIN(omsg, ctl_addr)->sin_port = temp_port;
582
                        OTOSIN(nmsg, ctl_addr)->sin_port = temp_port;
583

    
584
                        /* delete table entry */
585
                        if (so == req_tbl->udp_so) {
586
                                temp_req = req_tbl;
587
                                req_tbl = req_tbl->next;
588
                                free(temp_req);
589
                        } else {
590
                                temp_req = req_tbl;
591
                                for(req = req_tbl->next; req; req = req_next) {
592
                                        req_next = req->next;
593
                                        if (so == req->udp_so) {
594
                                                temp_req->next = req_next;
595
                                                free(req);
596
                                                break;
597
                                        } else {
598
                                                temp_req = req;
599
                                        }
600
                                }
601
                        }
602
                }
603
                
604
                return;                
605
#endif
606
                
607
        case EMU_CUSEEME:
608
        
609
                /*
610
                 * Cu-SeeMe emulation.
611
                 * Hopefully the packet is more that 16 bytes long. We don't
612
                 * do any other tests, just replace the address and port
613
                 * fields.
614
                 */ 
615
                if (m->m_len >= sizeof (*cu_head)) {
616
                        if (getsockname(so->s, (struct sockaddr *)&addr, &addrlen) < 0)
617
                                return;
618
                        cu_head = mtod(m, struct cu_header *);
619
                        cu_head->s_port = addr.sin_port;
620
                        cu_head->so_addr = our_addr.s_addr;
621
                }
622
                
623
                return;
624
        }
625
}
626

    
627
struct socket *
628
udp_listen(port, laddr, lport, flags)
629
        u_int port;
630
        u_int32_t laddr;
631
        u_int lport;
632
        int flags;
633
{
634
        struct sockaddr_in addr;
635
        struct socket *so;
636
        int addrlen = sizeof(struct sockaddr_in), opt = 1;
637
        
638
        if ((so = socreate()) == NULL) {
639
                free(so);
640
                return NULL;
641
        }
642
        so->s = socket(AF_INET,SOCK_DGRAM,0);
643
        so->so_expire = curtime + SO_EXPIRE;
644
        insque(so,&udb);
645

    
646
        addr.sin_family = AF_INET;
647
        addr.sin_addr.s_addr = INADDR_ANY;
648
        addr.sin_port = port;
649

    
650
        if (bind(so->s,(struct sockaddr *)&addr, addrlen) < 0) {
651
                udp_detach(so);
652
                return NULL;
653
        }
654
        setsockopt(so->s,SOL_SOCKET,SO_REUSEADDR,(char *)&opt,sizeof(int));
655
/*        setsockopt(so->s,SOL_SOCKET,SO_OOBINLINE,(char *)&opt,sizeof(int)); */
656
        
657
        getsockname(so->s,(struct sockaddr *)&addr,&addrlen);
658
        so->so_fport = addr.sin_port;
659
        if (addr.sin_addr.s_addr == 0 || addr.sin_addr.s_addr == loopback_addr.s_addr)
660
           so->so_faddr = our_addr;
661
        else
662
           so->so_faddr = addr.sin_addr;
663
        
664
        so->so_lport = lport;
665
        so->so_laddr.s_addr = laddr;
666
        if (flags != SS_FACCEPTONCE)
667
           so->so_expire = 0;
668
        
669
        so->so_state = SS_ISFCONNECTED;
670
        
671
        return so;
672
}