]> CyberLeo.Net >> Repos - FreeBSD/FreeBSD.git/blob - sys/netinet/udp_usrreq.c
Copy needed include files from EDK2. This is a minimal set gleened
[FreeBSD/FreeBSD.git] / sys / netinet / udp_usrreq.c
1 /*-
2  * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
3  *      The Regents of the University of California.
4  * Copyright (c) 2008 Robert N. M. Watson
5  * Copyright (c) 2010-2011 Juniper Networks, Inc.
6  * Copyright (c) 2014 Kevin Lo
7  * All rights reserved.
8  *
9  * Portions of this software were developed by Robert N. M. Watson under
10  * contract to Juniper Networks, Inc.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *      @(#)udp_usrreq.c        8.6 (Berkeley) 5/23/95
37  */
38
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41
42 #include "opt_inet.h"
43 #include "opt_inet6.h"
44 #include "opt_ipsec.h"
45 #include "opt_rss.h"
46
47 #include <sys/param.h>
48 #include <sys/domain.h>
49 #include <sys/eventhandler.h>
50 #include <sys/jail.h>
51 #include <sys/kernel.h>
52 #include <sys/lock.h>
53 #include <sys/malloc.h>
54 #include <sys/mbuf.h>
55 #include <sys/priv.h>
56 #include <sys/proc.h>
57 #include <sys/protosw.h>
58 #include <sys/sdt.h>
59 #include <sys/signalvar.h>
60 #include <sys/socket.h>
61 #include <sys/socketvar.h>
62 #include <sys/sx.h>
63 #include <sys/sysctl.h>
64 #include <sys/syslog.h>
65 #include <sys/systm.h>
66
67 #include <vm/uma.h>
68
69 #include <net/if.h>
70 #include <net/if_var.h>
71 #include <net/route.h>
72 #include <net/rss_config.h>
73
74 #include <netinet/in.h>
75 #include <netinet/in_kdtrace.h>
76 #include <netinet/in_pcb.h>
77 #include <netinet/in_systm.h>
78 #include <netinet/in_var.h>
79 #include <netinet/ip.h>
80 #ifdef INET6
81 #include <netinet/ip6.h>
82 #endif
83 #include <netinet/ip_icmp.h>
84 #include <netinet/icmp_var.h>
85 #include <netinet/ip_var.h>
86 #include <netinet/ip_options.h>
87 #ifdef INET6
88 #include <netinet6/ip6_var.h>
89 #endif
90 #include <netinet/udp.h>
91 #include <netinet/udp_var.h>
92 #include <netinet/udplite.h>
93 #include <netinet/in_rss.h>
94
95 #include <netipsec/ipsec_support.h>
96
97 #include <machine/in_cksum.h>
98
99 #include <security/mac/mac_framework.h>
100
101 /*
102  * UDP and UDP-Lite protocols implementation.
103  * Per RFC 768, August, 1980.
104  * Per RFC 3828, July, 2004.
105  */
106
107 /*
108  * BSD 4.2 defaulted the udp checksum to be off.  Turning off udp checksums
109  * removes the only data integrity mechanism for packets and malformed
110  * packets that would otherwise be discarded due to bad checksums, and may
111  * cause problems (especially for NFS data blocks).
112  */
113 VNET_DEFINE(int, udp_cksum) = 1;
114 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_VNET | CTLFLAG_RW,
115     &VNET_NAME(udp_cksum), 0, "compute udp checksum");
116
117 int     udp_log_in_vain = 0;
118 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_RW,
119     &udp_log_in_vain, 0, "Log all incoming UDP packets");
120
121 VNET_DEFINE(int, udp_blackhole) = 0;
122 SYSCTL_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_VNET | CTLFLAG_RW,
123     &VNET_NAME(udp_blackhole), 0,
124     "Do not send port unreachables for refused connects");
125
126 static VNET_DEFINE(int, udp_require_l2_bcast) = 0;
127 #define V_udp_require_l2_bcast          VNET(udp_require_l2_bcast)
128 SYSCTL_INT(_net_inet_udp, OID_AUTO, require_l2_bcast, CTLFLAG_VNET | CTLFLAG_RW,
129     &VNET_NAME(udp_require_l2_bcast), 0,
130     "Only treat packets sent to an L2 broadcast address as broadcast packets");
131
132 u_long  udp_sendspace = 9216;           /* really max datagram size */
133 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW,
134     &udp_sendspace, 0, "Maximum outgoing UDP datagram size");
135
136 u_long  udp_recvspace = 40 * (1024 +
137 #ifdef INET6
138                                       sizeof(struct sockaddr_in6)
139 #else
140                                       sizeof(struct sockaddr_in)
141 #endif
142                                       );        /* 40 1K datagrams */
143
144 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
145     &udp_recvspace, 0, "Maximum space for incoming UDP datagrams");
146
147 VNET_DEFINE(struct inpcbhead, udb);             /* from udp_var.h */
148 VNET_DEFINE(struct inpcbinfo, udbinfo);
149 VNET_DEFINE(struct inpcbhead, ulitecb);
150 VNET_DEFINE(struct inpcbinfo, ulitecbinfo);
151 static VNET_DEFINE(uma_zone_t, udpcb_zone);
152 #define V_udpcb_zone                    VNET(udpcb_zone)
153
154 #ifndef UDBHASHSIZE
155 #define UDBHASHSIZE     128
156 #endif
157
158 VNET_PCPUSTAT_DEFINE(struct udpstat, udpstat);          /* from udp_var.h */
159 VNET_PCPUSTAT_SYSINIT(udpstat);
160 SYSCTL_VNET_PCPUSTAT(_net_inet_udp, UDPCTL_STATS, stats, struct udpstat,
161     udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)");
162
163 #ifdef VIMAGE
164 VNET_PCPUSTAT_SYSUNINIT(udpstat);
165 #endif /* VIMAGE */
166 #ifdef INET
167 static void     udp_detach(struct socket *so);
168 static int      udp_output(struct inpcb *, struct mbuf *, struct sockaddr *,
169                     struct mbuf *, struct thread *);
170 #endif
171
172 static void
173 udp_zone_change(void *tag)
174 {
175
176         uma_zone_set_max(V_udbinfo.ipi_zone, maxsockets);
177         uma_zone_set_max(V_udpcb_zone, maxsockets);
178 }
179
180 static int
181 udp_inpcb_init(void *mem, int size, int flags)
182 {
183         struct inpcb *inp;
184
185         inp = mem;
186         INP_LOCK_INIT(inp, "inp", "udpinp");
187         return (0);
188 }
189
190 static int
191 udplite_inpcb_init(void *mem, int size, int flags)
192 {
193         struct inpcb *inp;
194
195         inp = mem;
196         INP_LOCK_INIT(inp, "inp", "udpliteinp");
197         return (0);
198 }
199
200 void
201 udp_init(void)
202 {
203
204         /*
205          * For now default to 2-tuple UDP hashing - until the fragment
206          * reassembly code can also update the flowid.
207          *
208          * Once we can calculate the flowid that way and re-establish
209          * a 4-tuple, flip this to 4-tuple.
210          */
211         in_pcbinfo_init(&V_udbinfo, "udp", &V_udb, UDBHASHSIZE, UDBHASHSIZE,
212             "udp_inpcb", udp_inpcb_init, NULL, 0,
213             IPI_HASHFIELDS_2TUPLE);
214         V_udpcb_zone = uma_zcreate("udpcb", sizeof(struct udpcb),
215             NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
216         uma_zone_set_max(V_udpcb_zone, maxsockets);
217         uma_zone_set_warning(V_udpcb_zone, "kern.ipc.maxsockets limit reached");
218         EVENTHANDLER_REGISTER(maxsockets_change, udp_zone_change, NULL,
219             EVENTHANDLER_PRI_ANY);
220 }
221
222 void
223 udplite_init(void)
224 {
225
226         in_pcbinfo_init(&V_ulitecbinfo, "udplite", &V_ulitecb, UDBHASHSIZE,
227             UDBHASHSIZE, "udplite_inpcb", udplite_inpcb_init, NULL,
228             0, IPI_HASHFIELDS_2TUPLE);
229 }
230
231 /*
232  * Kernel module interface for updating udpstat.  The argument is an index
233  * into udpstat treated as an array of u_long.  While this encodes the
234  * general layout of udpstat into the caller, it doesn't encode its location,
235  * so that future changes to add, for example, per-CPU stats support won't
236  * cause binary compatibility problems for kernel modules.
237  */
238 void
239 kmod_udpstat_inc(int statnum)
240 {
241
242         counter_u64_add(VNET(udpstat)[statnum], 1);
243 }
244
245 int
246 udp_newudpcb(struct inpcb *inp)
247 {
248         struct udpcb *up;
249
250         up = uma_zalloc(V_udpcb_zone, M_NOWAIT | M_ZERO);
251         if (up == NULL)
252                 return (ENOBUFS);
253         inp->inp_ppcb = up;
254         return (0);
255 }
256
257 void
258 udp_discardcb(struct udpcb *up)
259 {
260
261         uma_zfree(V_udpcb_zone, up);
262 }
263
264 #ifdef VIMAGE
265 static void
266 udp_destroy(void *unused __unused)
267 {
268
269         in_pcbinfo_destroy(&V_udbinfo);
270         uma_zdestroy(V_udpcb_zone);
271 }
272 VNET_SYSUNINIT(udp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, udp_destroy, NULL);
273
274 static void
275 udplite_destroy(void *unused __unused)
276 {
277
278         in_pcbinfo_destroy(&V_ulitecbinfo);
279 }
280 VNET_SYSUNINIT(udplite, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, udplite_destroy,
281     NULL);
282 #endif
283
284 #ifdef INET
285 /*
286  * Subroutine of udp_input(), which appends the provided mbuf chain to the
287  * passed pcb/socket.  The caller must provide a sockaddr_in via udp_in that
288  * contains the source address.  If the socket ends up being an IPv6 socket,
289  * udp_append() will convert to a sockaddr_in6 before passing the address
290  * into the socket code.
291  *
292  * In the normal case udp_append() will return 0, indicating that you
293  * must unlock the inp. However if a tunneling protocol is in place we increment
294  * the inpcb refcnt and unlock the inp, on return from the tunneling protocol we
295  * then decrement the reference count. If the inp_rele returns 1, indicating the
296  * inp is gone, we return that to the caller to tell them *not* to unlock
297  * the inp. In the case of multi-cast this will cause the distribution
298  * to stop (though most tunneling protocols known currently do *not* use
299  * multicast).
300  */
301 static int
302 udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off,
303     struct sockaddr_in *udp_in)
304 {
305         struct sockaddr *append_sa;
306         struct socket *so;
307         struct mbuf *tmpopts, *opts = NULL;
308 #ifdef INET6
309         struct sockaddr_in6 udp_in6;
310 #endif
311         struct udpcb *up;
312
313         INP_LOCK_ASSERT(inp);
314
315         /*
316          * Engage the tunneling protocol.
317          */
318         up = intoudpcb(inp);
319         if (up->u_tun_func != NULL) {
320                 in_pcbref(inp);
321                 INP_RUNLOCK(inp);
322                 (*up->u_tun_func)(n, off, inp, (struct sockaddr *)&udp_in[0],
323                     up->u_tun_ctx);
324                 INP_RLOCK(inp);
325                 return (in_pcbrele_rlocked(inp));
326         }
327
328         off += sizeof(struct udphdr);
329
330 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
331         /* Check AH/ESP integrity. */
332         if (IPSEC_ENABLED(ipv4) &&
333             IPSEC_CHECK_POLICY(ipv4, n, inp) != 0) {
334                 m_freem(n);
335                 return (0);
336         }
337         if (up->u_flags & UF_ESPINUDP) {/* IPSec UDP encaps. */
338                 if (IPSEC_ENABLED(ipv4) &&
339                     UDPENCAP_INPUT(n, off, AF_INET) != 0)
340                         return (0);     /* Consumed. */
341         }
342 #endif /* IPSEC */
343 #ifdef MAC
344         if (mac_inpcb_check_deliver(inp, n) != 0) {
345                 m_freem(n);
346                 return (0);
347         }
348 #endif /* MAC */
349         if (inp->inp_flags & INP_CONTROLOPTS ||
350             inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) {
351 #ifdef INET6
352                 if (inp->inp_vflag & INP_IPV6)
353                         (void)ip6_savecontrol_v4(inp, n, &opts, NULL);
354                 else
355 #endif /* INET6 */
356                         ip_savecontrol(inp, &opts, ip, n);
357         }
358         if ((inp->inp_vflag & INP_IPV4) && (inp->inp_flags2 & INP_ORIGDSTADDR)) {
359                 tmpopts = sbcreatecontrol((caddr_t)&udp_in[1],
360                         sizeof(struct sockaddr_in), IP_ORIGDSTADDR, IPPROTO_IP);
361                 if (tmpopts) {
362                         if (opts) {
363                                 tmpopts->m_next = opts;
364                                 opts = tmpopts;
365                         } else
366                                 opts = tmpopts;
367                 }
368         }
369 #ifdef INET6
370         if (inp->inp_vflag & INP_IPV6) {
371                 bzero(&udp_in6, sizeof(udp_in6));
372                 udp_in6.sin6_len = sizeof(udp_in6);
373                 udp_in6.sin6_family = AF_INET6;
374                 in6_sin_2_v4mapsin6(&udp_in[0], &udp_in6);
375                 append_sa = (struct sockaddr *)&udp_in6;
376         } else
377 #endif /* INET6 */
378                 append_sa = (struct sockaddr *)&udp_in[0];
379         m_adj(n, off);
380
381         so = inp->inp_socket;
382         SOCKBUF_LOCK(&so->so_rcv);
383         if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) {
384                 SOCKBUF_UNLOCK(&so->so_rcv);
385                 m_freem(n);
386                 if (opts)
387                         m_freem(opts);
388                 UDPSTAT_INC(udps_fullsock);
389         } else
390                 sorwakeup_locked(so);
391         return (0);
392 }
393
394 int
395 udp_input(struct mbuf **mp, int *offp, int proto)
396 {
397         struct ip *ip;
398         struct udphdr *uh;
399         struct ifnet *ifp;
400         struct inpcb *inp;
401         uint16_t len, ip_len;
402         struct inpcbinfo *pcbinfo;
403         struct ip save_ip;
404         struct sockaddr_in udp_in[2];
405         struct mbuf *m;
406         struct m_tag *fwd_tag;
407         int cscov_partial, iphlen;
408
409         m = *mp;
410         iphlen = *offp;
411         ifp = m->m_pkthdr.rcvif;
412         *mp = NULL;
413         UDPSTAT_INC(udps_ipackets);
414
415         /*
416          * Strip IP options, if any; should skip this, make available to
417          * user, and use on returned packets, but we don't yet have a way to
418          * check the checksum with options still present.
419          */
420         if (iphlen > sizeof (struct ip)) {
421                 ip_stripoptions(m);
422                 iphlen = sizeof(struct ip);
423         }
424
425         /*
426          * Get IP and UDP header together in first mbuf.
427          */
428         ip = mtod(m, struct ip *);
429         if (m->m_len < iphlen + sizeof(struct udphdr)) {
430                 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == NULL) {
431                         UDPSTAT_INC(udps_hdrops);
432                         return (IPPROTO_DONE);
433                 }
434                 ip = mtod(m, struct ip *);
435         }
436         uh = (struct udphdr *)((caddr_t)ip + iphlen);
437         cscov_partial = (proto == IPPROTO_UDPLITE) ? 1 : 0;
438
439         /*
440          * Destination port of 0 is illegal, based on RFC768.
441          */
442         if (uh->uh_dport == 0)
443                 goto badunlocked;
444
445         /*
446          * Construct sockaddr format source address.  Stuff source address
447          * and datagram in user buffer.
448          */
449         bzero(&udp_in[0], sizeof(struct sockaddr_in) * 2);
450         udp_in[0].sin_len = sizeof(struct sockaddr_in);
451         udp_in[0].sin_family = AF_INET;
452         udp_in[0].sin_port = uh->uh_sport;
453         udp_in[0].sin_addr = ip->ip_src;
454         udp_in[1].sin_len = sizeof(struct sockaddr_in);
455         udp_in[1].sin_family = AF_INET;
456         udp_in[1].sin_port = uh->uh_dport;
457         udp_in[1].sin_addr = ip->ip_dst;
458
459         /*
460          * Make mbuf data length reflect UDP length.  If not enough data to
461          * reflect UDP length, drop.
462          */
463         len = ntohs((u_short)uh->uh_ulen);
464         ip_len = ntohs(ip->ip_len) - iphlen;
465         if (proto == IPPROTO_UDPLITE && (len == 0 || len == ip_len)) {
466                 /* Zero means checksum over the complete packet. */
467                 if (len == 0)
468                         len = ip_len;
469                 cscov_partial = 0;
470         }
471         if (ip_len != len) {
472                 if (len > ip_len || len < sizeof(struct udphdr)) {
473                         UDPSTAT_INC(udps_badlen);
474                         goto badunlocked;
475                 }
476                 if (proto == IPPROTO_UDP)
477                         m_adj(m, len - ip_len);
478         }
479
480         /*
481          * Save a copy of the IP header in case we want restore it for
482          * sending an ICMP error message in response.
483          */
484         if (!V_udp_blackhole)
485                 save_ip = *ip;
486         else
487                 memset(&save_ip, 0, sizeof(save_ip));
488
489         /*
490          * Checksum extended UDP header and data.
491          */
492         if (uh->uh_sum) {
493                 u_short uh_sum;
494
495                 if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID) &&
496                     !cscov_partial) {
497                         if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
498                                 uh_sum = m->m_pkthdr.csum_data;
499                         else
500                                 uh_sum = in_pseudo(ip->ip_src.s_addr,
501                                     ip->ip_dst.s_addr, htonl((u_short)len +
502                                     m->m_pkthdr.csum_data + proto));
503                         uh_sum ^= 0xffff;
504                 } else {
505                         char b[9];
506
507                         bcopy(((struct ipovly *)ip)->ih_x1, b, 9);
508                         bzero(((struct ipovly *)ip)->ih_x1, 9);
509                         ((struct ipovly *)ip)->ih_len = (proto == IPPROTO_UDP) ?
510                             uh->uh_ulen : htons(ip_len);
511                         uh_sum = in_cksum(m, len + sizeof (struct ip));
512                         bcopy(b, ((struct ipovly *)ip)->ih_x1, 9);
513                 }
514                 if (uh_sum) {
515                         UDPSTAT_INC(udps_badsum);
516                         m_freem(m);
517                         return (IPPROTO_DONE);
518                 }
519         } else {
520                 if (proto == IPPROTO_UDP) {
521                         UDPSTAT_INC(udps_nosum);
522                 } else {
523                         /* UDPLite requires a checksum */
524                         /* XXX: What is the right UDPLite MIB counter here? */
525                         m_freem(m);
526                         return (IPPROTO_DONE);
527                 }
528         }
529
530         pcbinfo = udp_get_inpcbinfo(proto);
531         if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) ||
532             ((!V_udp_require_l2_bcast || m->m_flags & M_BCAST) &&
533             in_broadcast(ip->ip_dst, ifp))) {
534                 struct inpcb *last;
535                 struct inpcbhead *pcblist;
536                 struct ip_moptions *imo;
537
538                 INP_INFO_RLOCK(pcbinfo);
539                 pcblist = udp_get_pcblist(proto);
540                 last = NULL;
541                 LIST_FOREACH(inp, pcblist, inp_list) {
542                         if (inp->inp_lport != uh->uh_dport)
543                                 continue;
544 #ifdef INET6
545                         if ((inp->inp_vflag & INP_IPV4) == 0)
546                                 continue;
547 #endif
548                         if (inp->inp_laddr.s_addr != INADDR_ANY &&
549                             inp->inp_laddr.s_addr != ip->ip_dst.s_addr)
550                                 continue;
551                         if (inp->inp_faddr.s_addr != INADDR_ANY &&
552                             inp->inp_faddr.s_addr != ip->ip_src.s_addr)
553                                 continue;
554                         if (inp->inp_fport != 0 &&
555                             inp->inp_fport != uh->uh_sport)
556                                 continue;
557
558                         INP_RLOCK(inp);
559
560                         /*
561                          * XXXRW: Because we weren't holding either the inpcb
562                          * or the hash lock when we checked for a match
563                          * before, we should probably recheck now that the
564                          * inpcb lock is held.
565                          */
566
567                         /*
568                          * Handle socket delivery policy for any-source
569                          * and source-specific multicast. [RFC3678]
570                          */
571                         imo = inp->inp_moptions;
572                         if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
573                                 struct sockaddr_in       group;
574                                 int                      blocked;
575                                 if (imo == NULL) {
576                                         INP_RUNLOCK(inp);
577                                         continue;
578                                 }
579                                 bzero(&group, sizeof(struct sockaddr_in));
580                                 group.sin_len = sizeof(struct sockaddr_in);
581                                 group.sin_family = AF_INET;
582                                 group.sin_addr = ip->ip_dst;
583
584                                 blocked = imo_multi_filter(imo, ifp,
585                                         (struct sockaddr *)&group,
586                                         (struct sockaddr *)&udp_in[0]);
587                                 if (blocked != MCAST_PASS) {
588                                         if (blocked == MCAST_NOTGMEMBER)
589                                                 IPSTAT_INC(ips_notmember);
590                                         if (blocked == MCAST_NOTSMEMBER ||
591                                             blocked == MCAST_MUTED)
592                                                 UDPSTAT_INC(udps_filtermcast);
593                                         INP_RUNLOCK(inp);
594                                         continue;
595                                 }
596                         }
597                         if (last != NULL) {
598                                 struct mbuf *n;
599
600                                 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) !=
601                                     NULL) {
602                                         UDP_PROBE(receive, NULL, last, ip,
603                                             last, uh);
604                                         if (udp_append(last, ip, n, iphlen,
605                                                 udp_in)) {
606                                                 goto inp_lost;
607                                         }
608                                 }
609                                 INP_RUNLOCK(last);
610                         }
611                         last = inp;
612                         /*
613                          * Don't look for additional matches if this one does
614                          * not have either the SO_REUSEPORT or SO_REUSEADDR
615                          * socket options set.  This heuristic avoids
616                          * searching through all pcbs in the common case of a
617                          * non-shared port.  It assumes that an application
618                          * will never clear these options after setting them.
619                          */
620                         if ((last->inp_socket->so_options &
621                             (SO_REUSEPORT|SO_REUSEADDR)) == 0)
622                                 break;
623                 }
624
625                 if (last == NULL) {
626                         /*
627                          * No matching pcb found; discard datagram.  (No need
628                          * to send an ICMP Port Unreachable for a broadcast
629                          * or multicast datgram.)
630                          */
631                         UDPSTAT_INC(udps_noportbcast);
632                         if (inp)
633                                 INP_RUNLOCK(inp);
634                         INP_INFO_RUNLOCK(pcbinfo);
635                         goto badunlocked;
636                 }
637                 UDP_PROBE(receive, NULL, last, ip, last, uh);
638                 if (udp_append(last, ip, m, iphlen, udp_in) == 0) 
639                         INP_RUNLOCK(last);
640         inp_lost:
641                 INP_INFO_RUNLOCK(pcbinfo);
642                 return (IPPROTO_DONE);
643         }
644
645         /*
646          * Locate pcb for datagram.
647          */
648
649         /*
650          * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
651          */
652         if ((m->m_flags & M_IP_NEXTHOP) &&
653             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
654                 struct sockaddr_in *next_hop;
655
656                 next_hop = (struct sockaddr_in *)(fwd_tag + 1);
657
658                 /*
659                  * Transparently forwarded. Pretend to be the destination.
660                  * Already got one like this?
661                  */
662                 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
663                     ip->ip_dst, uh->uh_dport, INPLOOKUP_RLOCKPCB, ifp, m);
664                 if (!inp) {
665                         /*
666                          * It's new.  Try to find the ambushing socket.
667                          * Because we've rewritten the destination address,
668                          * any hardware-generated hash is ignored.
669                          */
670                         inp = in_pcblookup(pcbinfo, ip->ip_src,
671                             uh->uh_sport, next_hop->sin_addr,
672                             next_hop->sin_port ? htons(next_hop->sin_port) :
673                             uh->uh_dport, INPLOOKUP_WILDCARD |
674                             INPLOOKUP_RLOCKPCB, ifp);
675                 }
676                 /* Remove the tag from the packet. We don't need it anymore. */
677                 m_tag_delete(m, fwd_tag);
678                 m->m_flags &= ~M_IP_NEXTHOP;
679         } else
680                 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
681                     ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD |
682                     INPLOOKUP_RLOCKPCB, ifp, m);
683         if (inp == NULL) {
684                 if (udp_log_in_vain) {
685                         char src[INET_ADDRSTRLEN];
686                         char dst[INET_ADDRSTRLEN];
687
688                         log(LOG_INFO,
689                             "Connection attempt to UDP %s:%d from %s:%d\n",
690                             inet_ntoa_r(ip->ip_dst, dst), ntohs(uh->uh_dport),
691                             inet_ntoa_r(ip->ip_src, src), ntohs(uh->uh_sport));
692                 }
693                 UDPSTAT_INC(udps_noport);
694                 if (m->m_flags & (M_BCAST | M_MCAST)) {
695                         UDPSTAT_INC(udps_noportbcast);
696                         goto badunlocked;
697                 }
698                 if (V_udp_blackhole)
699                         goto badunlocked;
700                 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0)
701                         goto badunlocked;
702                 *ip = save_ip;
703                 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
704                 return (IPPROTO_DONE);
705         }
706
707         /*
708          * Check the minimum TTL for socket.
709          */
710         INP_RLOCK_ASSERT(inp);
711         if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) {
712                 INP_RUNLOCK(inp);
713                 m_freem(m);
714                 return (IPPROTO_DONE);
715         }
716         if (cscov_partial) {
717                 struct udpcb *up;
718
719                 up = intoudpcb(inp);
720                 if (up->u_rxcslen == 0 || up->u_rxcslen > len) {
721                         INP_RUNLOCK(inp);
722                         m_freem(m);
723                         return (IPPROTO_DONE);
724                 }
725         }
726
727         UDP_PROBE(receive, NULL, inp, ip, inp, uh);
728         if (udp_append(inp, ip, m, iphlen, udp_in) == 0) 
729                 INP_RUNLOCK(inp);
730         return (IPPROTO_DONE);
731
732 badunlocked:
733         m_freem(m);
734         return (IPPROTO_DONE);
735 }
736 #endif /* INET */
737
738 /*
739  * Notify a udp user of an asynchronous error; just wake up so that they can
740  * collect error status.
741  */
742 struct inpcb *
743 udp_notify(struct inpcb *inp, int errno)
744 {
745
746         /*
747          * While udp_ctlinput() always calls udp_notify() with a read lock
748          * when invoking it directly, in_pcbnotifyall() currently uses write
749          * locks due to sharing code with TCP.  For now, accept either a read
750          * or a write lock, but a read lock is sufficient.
751          */
752         INP_LOCK_ASSERT(inp);
753         if ((errno == EHOSTUNREACH || errno == ENETUNREACH ||
754              errno == EHOSTDOWN) && inp->inp_route.ro_rt) {
755                 RTFREE(inp->inp_route.ro_rt);
756                 inp->inp_route.ro_rt = (struct rtentry *)NULL;
757         }
758
759         inp->inp_socket->so_error = errno;
760         sorwakeup(inp->inp_socket);
761         sowwakeup(inp->inp_socket);
762         return (inp);
763 }
764
765 #ifdef INET
766 static void
767 udp_common_ctlinput(int cmd, struct sockaddr *sa, void *vip,
768     struct inpcbinfo *pcbinfo)
769 {
770         struct ip *ip = vip;
771         struct udphdr *uh;
772         struct in_addr faddr;
773         struct inpcb *inp;
774
775         faddr = ((struct sockaddr_in *)sa)->sin_addr;
776         if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
777                 return;
778
779         if (PRC_IS_REDIRECT(cmd)) {
780                 /* signal EHOSTDOWN, as it flushes the cached route */
781                 in_pcbnotifyall(&V_udbinfo, faddr, EHOSTDOWN, udp_notify);
782                 return;
783         }
784
785         /*
786          * Hostdead is ugly because it goes linearly through all PCBs.
787          *
788          * XXX: We never get this from ICMP, otherwise it makes an excellent
789          * DoS attack on machines with many connections.
790          */
791         if (cmd == PRC_HOSTDEAD)
792                 ip = NULL;
793         else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0)
794                 return;
795         if (ip != NULL) {
796                 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
797                 inp = in_pcblookup(pcbinfo, faddr, uh->uh_dport,
798                     ip->ip_src, uh->uh_sport, INPLOOKUP_RLOCKPCB, NULL);
799                 if (inp != NULL) {
800                         INP_RLOCK_ASSERT(inp);
801                         if (inp->inp_socket != NULL) {
802                                 udp_notify(inp, inetctlerrmap[cmd]);
803                         }
804                         INP_RUNLOCK(inp);
805                 } else {
806                         inp = in_pcblookup(pcbinfo, faddr, uh->uh_dport,
807                                            ip->ip_src, uh->uh_sport,
808                                            INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
809                         if (inp != NULL) {
810                                 struct udpcb *up;
811
812                                 up = intoudpcb(inp);
813                                 if (up->u_icmp_func != NULL) {
814                                         INP_RUNLOCK(inp);
815                                         (*up->u_icmp_func)(cmd, sa, vip, up->u_tun_ctx);
816                                 } else {
817                                         INP_RUNLOCK(inp);
818                                 }
819                         }
820                 }
821         } else
822                 in_pcbnotifyall(pcbinfo, faddr, inetctlerrmap[cmd],
823                     udp_notify);
824 }
825 void
826 udp_ctlinput(int cmd, struct sockaddr *sa, void *vip)
827 {
828
829         return (udp_common_ctlinput(cmd, sa, vip, &V_udbinfo));
830 }
831
832 void
833 udplite_ctlinput(int cmd, struct sockaddr *sa, void *vip)
834 {
835
836         return (udp_common_ctlinput(cmd, sa, vip, &V_ulitecbinfo));
837 }
838 #endif /* INET */
839
840 static int
841 udp_pcblist(SYSCTL_HANDLER_ARGS)
842 {
843         int error, i, n;
844         struct inpcb *inp, **inp_list;
845         inp_gen_t gencnt;
846         struct xinpgen xig;
847
848         /*
849          * The process of preparing the PCB list is too time-consuming and
850          * resource-intensive to repeat twice on every request.
851          */
852         if (req->oldptr == 0) {
853                 n = V_udbinfo.ipi_count;
854                 n += imax(n / 8, 10);
855                 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb);
856                 return (0);
857         }
858
859         if (req->newptr != 0)
860                 return (EPERM);
861
862         /*
863          * OK, now we're committed to doing something.
864          */
865         INP_INFO_RLOCK(&V_udbinfo);
866         gencnt = V_udbinfo.ipi_gencnt;
867         n = V_udbinfo.ipi_count;
868         INP_INFO_RUNLOCK(&V_udbinfo);
869
870         error = sysctl_wire_old_buffer(req, 2 * (sizeof xig)
871                 + n * sizeof(struct xinpcb));
872         if (error != 0)
873                 return (error);
874
875         xig.xig_len = sizeof xig;
876         xig.xig_count = n;
877         xig.xig_gen = gencnt;
878         xig.xig_sogen = so_gencnt;
879         error = SYSCTL_OUT(req, &xig, sizeof xig);
880         if (error)
881                 return (error);
882
883         inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK);
884         if (inp_list == NULL)
885                 return (ENOMEM);
886
887         INP_INFO_RLOCK(&V_udbinfo);
888         for (inp = LIST_FIRST(V_udbinfo.ipi_listhead), i = 0; inp && i < n;
889              inp = LIST_NEXT(inp, inp_list)) {
890                 INP_WLOCK(inp);
891                 if (inp->inp_gencnt <= gencnt &&
892                     cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
893                         in_pcbref(inp);
894                         inp_list[i++] = inp;
895                 }
896                 INP_WUNLOCK(inp);
897         }
898         INP_INFO_RUNLOCK(&V_udbinfo);
899         n = i;
900
901         error = 0;
902         for (i = 0; i < n; i++) {
903                 inp = inp_list[i];
904                 INP_RLOCK(inp);
905                 if (inp->inp_gencnt <= gencnt) {
906                         struct xinpcb xi;
907
908                         bzero(&xi, sizeof(xi));
909                         xi.xi_len = sizeof xi;
910                         /* XXX should avoid extra copy */
911                         bcopy(inp, &xi.xi_inp, sizeof *inp);
912                         if (inp->inp_socket)
913                                 sotoxsocket(inp->inp_socket, &xi.xi_socket);
914                         xi.xi_inp.inp_gencnt = inp->inp_gencnt;
915                         INP_RUNLOCK(inp);
916                         error = SYSCTL_OUT(req, &xi, sizeof xi);
917                 } else
918                         INP_RUNLOCK(inp);
919         }
920         INP_INFO_WLOCK(&V_udbinfo);
921         for (i = 0; i < n; i++) {
922                 inp = inp_list[i];
923                 INP_RLOCK(inp);
924                 if (!in_pcbrele_rlocked(inp))
925                         INP_RUNLOCK(inp);
926         }
927         INP_INFO_WUNLOCK(&V_udbinfo);
928
929         if (!error) {
930                 /*
931                  * Give the user an updated idea of our state.  If the
932                  * generation differs from what we told her before, she knows
933                  * that something happened while we were processing this
934                  * request, and it might be necessary to retry.
935                  */
936                 INP_INFO_RLOCK(&V_udbinfo);
937                 xig.xig_gen = V_udbinfo.ipi_gencnt;
938                 xig.xig_sogen = so_gencnt;
939                 xig.xig_count = V_udbinfo.ipi_count;
940                 INP_INFO_RUNLOCK(&V_udbinfo);
941                 error = SYSCTL_OUT(req, &xig, sizeof xig);
942         }
943         free(inp_list, M_TEMP);
944         return (error);
945 }
946
947 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist,
948     CTLTYPE_OPAQUE | CTLFLAG_RD, NULL, 0,
949     udp_pcblist, "S,xinpcb", "List of active UDP sockets");
950
951 #ifdef INET
952 static int
953 udp_getcred(SYSCTL_HANDLER_ARGS)
954 {
955         struct xucred xuc;
956         struct sockaddr_in addrs[2];
957         struct inpcb *inp;
958         int error;
959
960         error = priv_check(req->td, PRIV_NETINET_GETCRED);
961         if (error)
962                 return (error);
963         error = SYSCTL_IN(req, addrs, sizeof(addrs));
964         if (error)
965                 return (error);
966         inp = in_pcblookup(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port,
967             addrs[0].sin_addr, addrs[0].sin_port,
968             INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
969         if (inp != NULL) {
970                 INP_RLOCK_ASSERT(inp);
971                 if (inp->inp_socket == NULL)
972                         error = ENOENT;
973                 if (error == 0)
974                         error = cr_canseeinpcb(req->td->td_ucred, inp);
975                 if (error == 0)
976                         cru2x(inp->inp_cred, &xuc);
977                 INP_RUNLOCK(inp);
978         } else
979                 error = ENOENT;
980         if (error == 0)
981                 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
982         return (error);
983 }
984
985 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred,
986     CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0,
987     udp_getcred, "S,xucred", "Get the xucred of a UDP connection");
988 #endif /* INET */
989
990 int
991 udp_ctloutput(struct socket *so, struct sockopt *sopt)
992 {
993         struct inpcb *inp;
994         struct udpcb *up;
995         int isudplite, error, optval;
996
997         error = 0;
998         isudplite = (so->so_proto->pr_protocol == IPPROTO_UDPLITE) ? 1 : 0;
999         inp = sotoinpcb(so);
1000         KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
1001         INP_WLOCK(inp);
1002         if (sopt->sopt_level != so->so_proto->pr_protocol) {
1003 #ifdef INET6
1004                 if (INP_CHECK_SOCKAF(so, AF_INET6)) {
1005                         INP_WUNLOCK(inp);
1006                         error = ip6_ctloutput(so, sopt);
1007                 }
1008 #endif
1009 #if defined(INET) && defined(INET6)
1010                 else
1011 #endif
1012 #ifdef INET
1013                 {
1014                         INP_WUNLOCK(inp);
1015                         error = ip_ctloutput(so, sopt);
1016                 }
1017 #endif
1018                 return (error);
1019         }
1020
1021         switch (sopt->sopt_dir) {
1022         case SOPT_SET:
1023                 switch (sopt->sopt_name) {
1024 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1025 #ifdef INET
1026                 case UDP_ENCAP:
1027                         if (!IPSEC_ENABLED(ipv4)) {
1028                                 INP_WUNLOCK(inp);
1029                                 return (ENOPROTOOPT);
1030                         }
1031                         error = UDPENCAP_PCBCTL(inp, sopt);
1032                         break;
1033 #endif /* INET */
1034 #endif /* IPSEC */
1035                 case UDPLITE_SEND_CSCOV:
1036                 case UDPLITE_RECV_CSCOV:
1037                         if (!isudplite) {
1038                                 INP_WUNLOCK(inp);
1039                                 error = ENOPROTOOPT;
1040                                 break;
1041                         }
1042                         INP_WUNLOCK(inp);
1043                         error = sooptcopyin(sopt, &optval, sizeof(optval),
1044                             sizeof(optval));
1045                         if (error != 0)
1046                                 break;
1047                         inp = sotoinpcb(so);
1048                         KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
1049                         INP_WLOCK(inp);
1050                         up = intoudpcb(inp);
1051                         KASSERT(up != NULL, ("%s: up == NULL", __func__));
1052                         if ((optval != 0 && optval < 8) || (optval > 65535)) {
1053                                 INP_WUNLOCK(inp);
1054                                 error = EINVAL;
1055                                 break;
1056                         }
1057                         if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
1058                                 up->u_txcslen = optval;
1059                         else
1060                                 up->u_rxcslen = optval;
1061                         INP_WUNLOCK(inp);
1062                         break;
1063                 default:
1064                         INP_WUNLOCK(inp);
1065                         error = ENOPROTOOPT;
1066                         break;
1067                 }
1068                 break;
1069         case SOPT_GET:
1070                 switch (sopt->sopt_name) {
1071 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1072 #ifdef INET
1073                 case UDP_ENCAP:
1074                         if (!IPSEC_ENABLED(ipv4)) {
1075                                 INP_WUNLOCK(inp);
1076                                 return (ENOPROTOOPT);
1077                         }
1078                         error = UDPENCAP_PCBCTL(inp, sopt);
1079                         break;
1080 #endif /* INET */
1081 #endif /* IPSEC */
1082                 case UDPLITE_SEND_CSCOV:
1083                 case UDPLITE_RECV_CSCOV:
1084                         if (!isudplite) {
1085                                 INP_WUNLOCK(inp);
1086                                 error = ENOPROTOOPT;
1087                                 break;
1088                         }
1089                         up = intoudpcb(inp);
1090                         KASSERT(up != NULL, ("%s: up == NULL", __func__));
1091                         if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
1092                                 optval = up->u_txcslen;
1093                         else
1094                                 optval = up->u_rxcslen;
1095                         INP_WUNLOCK(inp);
1096                         error = sooptcopyout(sopt, &optval, sizeof(optval));
1097                         break;
1098                 default:
1099                         INP_WUNLOCK(inp);
1100                         error = ENOPROTOOPT;
1101                         break;
1102                 }
1103                 break;
1104         }       
1105         return (error);
1106 }
1107
1108 #ifdef INET
1109 #define UH_WLOCKED      2
1110 #define UH_RLOCKED      1
1111 #define UH_UNLOCKED     0
1112 static int
1113 udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr,
1114     struct mbuf *control, struct thread *td)
1115 {
1116         struct udpiphdr *ui;
1117         int len = m->m_pkthdr.len;
1118         struct in_addr faddr, laddr;
1119         struct cmsghdr *cm;
1120         struct inpcbinfo *pcbinfo;
1121         struct sockaddr_in *sin, src;
1122         int cscov_partial = 0;
1123         int error = 0;
1124         int ipflags;
1125         u_short fport, lport;
1126         int unlock_udbinfo, unlock_inp;
1127         u_char tos;
1128         uint8_t pr;
1129         uint16_t cscov = 0;
1130         uint32_t flowid = 0;
1131         uint8_t flowtype = M_HASHTYPE_NONE;
1132
1133         /*
1134          * udp_output() may need to temporarily bind or connect the current
1135          * inpcb.  As such, we don't know up front whether we will need the
1136          * pcbinfo lock or not.  Do any work to decide what is needed up
1137          * front before acquiring any locks.
1138          */
1139         if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
1140                 if (control)
1141                         m_freem(control);
1142                 m_freem(m);
1143                 return (EMSGSIZE);
1144         }
1145
1146         src.sin_family = 0;
1147         sin = (struct sockaddr_in *)addr;
1148         if (sin == NULL ||
1149             (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) {
1150                 INP_WLOCK(inp);
1151                 unlock_inp = UH_WLOCKED;
1152         } else {
1153                 INP_RLOCK(inp);
1154                 unlock_inp = UH_RLOCKED;
1155         }
1156         tos = inp->inp_ip_tos;
1157         if (control != NULL) {
1158                 /*
1159                  * XXX: Currently, we assume all the optional information is
1160                  * stored in a single mbuf.
1161                  */
1162                 if (control->m_next) {
1163                         if (unlock_inp == UH_WLOCKED)
1164                                 INP_WUNLOCK(inp);
1165                         else
1166                                 INP_RUNLOCK(inp);
1167                         m_freem(control);
1168                         m_freem(m);
1169                         return (EINVAL);
1170                 }
1171                 for (; control->m_len > 0;
1172                     control->m_data += CMSG_ALIGN(cm->cmsg_len),
1173                     control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
1174                         cm = mtod(control, struct cmsghdr *);
1175                         if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0
1176                             || cm->cmsg_len > control->m_len) {
1177                                 error = EINVAL;
1178                                 break;
1179                         }
1180                         if (cm->cmsg_level != IPPROTO_IP)
1181                                 continue;
1182
1183                         switch (cm->cmsg_type) {
1184                         case IP_SENDSRCADDR:
1185                                 if (cm->cmsg_len !=
1186                                     CMSG_LEN(sizeof(struct in_addr))) {
1187                                         error = EINVAL;
1188                                         break;
1189                                 }
1190                                 bzero(&src, sizeof(src));
1191                                 src.sin_family = AF_INET;
1192                                 src.sin_len = sizeof(src);
1193                                 src.sin_port = inp->inp_lport;
1194                                 src.sin_addr =
1195                                     *(struct in_addr *)CMSG_DATA(cm);
1196                                 break;
1197
1198                         case IP_TOS:
1199                                 if (cm->cmsg_len != CMSG_LEN(sizeof(u_char))) {
1200                                         error = EINVAL;
1201                                         break;
1202                                 }
1203                                 tos = *(u_char *)CMSG_DATA(cm);
1204                                 break;
1205
1206                         case IP_FLOWID:
1207                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1208                                         error = EINVAL;
1209                                         break;
1210                                 }
1211                                 flowid = *(uint32_t *) CMSG_DATA(cm);
1212                                 break;
1213
1214                         case IP_FLOWTYPE:
1215                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1216                                         error = EINVAL;
1217                                         break;
1218                                 }
1219                                 flowtype = *(uint32_t *) CMSG_DATA(cm);
1220                                 break;
1221
1222 #ifdef  RSS
1223                         case IP_RSSBUCKETID:
1224                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1225                                         error = EINVAL;
1226                                         break;
1227                                 }
1228                                 /* This is just a placeholder for now */
1229                                 break;
1230 #endif  /* RSS */
1231                         default:
1232                                 error = ENOPROTOOPT;
1233                                 break;
1234                         }
1235                         if (error)
1236                                 break;
1237                 }
1238                 m_freem(control);
1239         }
1240         if (error) {
1241                 if (unlock_inp == UH_WLOCKED)
1242                         INP_WUNLOCK(inp);
1243                 else
1244                         INP_RUNLOCK(inp);
1245                 m_freem(m);
1246                 return (error);
1247         }
1248
1249         /*
1250          * Depending on whether or not the application has bound or connected
1251          * the socket, we may have to do varying levels of work.  The optimal
1252          * case is for a connected UDP socket, as a global lock isn't
1253          * required at all.
1254          *
1255          * In order to decide which we need, we require stability of the
1256          * inpcb binding, which we ensure by acquiring a read lock on the
1257          * inpcb.  This doesn't strictly follow the lock order, so we play
1258          * the trylock and retry game; note that we may end up with more
1259          * conservative locks than required the second time around, so later
1260          * assertions have to accept that.  Further analysis of the number of
1261          * misses under contention is required.
1262          *
1263          * XXXRW: Check that hash locking update here is correct.
1264          */
1265         pr = inp->inp_socket->so_proto->pr_protocol;
1266         pcbinfo = udp_get_inpcbinfo(pr);
1267         sin = (struct sockaddr_in *)addr;
1268         if (sin != NULL &&
1269             (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) {
1270                 INP_HASH_WLOCK(pcbinfo);
1271                 unlock_udbinfo = UH_WLOCKED;
1272         } else if ((sin != NULL && (
1273             (sin->sin_addr.s_addr == INADDR_ANY) ||
1274             (sin->sin_addr.s_addr == INADDR_BROADCAST) ||
1275             (inp->inp_laddr.s_addr == INADDR_ANY) ||
1276             (inp->inp_lport == 0))) ||
1277             (src.sin_family == AF_INET)) {
1278                 INP_HASH_RLOCK(pcbinfo);
1279                 unlock_udbinfo = UH_RLOCKED;
1280         } else
1281                 unlock_udbinfo = UH_UNLOCKED;
1282
1283         /*
1284          * If the IP_SENDSRCADDR control message was specified, override the
1285          * source address for this datagram.  Its use is invalidated if the
1286          * address thus specified is incomplete or clobbers other inpcbs.
1287          */
1288         laddr = inp->inp_laddr;
1289         lport = inp->inp_lport;
1290         if (src.sin_family == AF_INET) {
1291                 INP_HASH_LOCK_ASSERT(pcbinfo);
1292                 if ((lport == 0) ||
1293                     (laddr.s_addr == INADDR_ANY &&
1294                      src.sin_addr.s_addr == INADDR_ANY)) {
1295                         error = EINVAL;
1296                         goto release;
1297                 }
1298                 error = in_pcbbind_setup(inp, (struct sockaddr *)&src,
1299                     &laddr.s_addr, &lport, td->td_ucred);
1300                 if (error)
1301                         goto release;
1302         }
1303
1304         /*
1305          * If a UDP socket has been connected, then a local address/port will
1306          * have been selected and bound.
1307          *
1308          * If a UDP socket has not been connected to, then an explicit
1309          * destination address must be used, in which case a local
1310          * address/port may not have been selected and bound.
1311          */
1312         if (sin != NULL) {
1313                 INP_LOCK_ASSERT(inp);
1314                 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1315                         error = EISCONN;
1316                         goto release;
1317                 }
1318
1319                 /*
1320                  * Jail may rewrite the destination address, so let it do
1321                  * that before we use it.
1322                  */
1323                 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1324                 if (error)
1325                         goto release;
1326
1327                 /*
1328                  * If a local address or port hasn't yet been selected, or if
1329                  * the destination address needs to be rewritten due to using
1330                  * a special INADDR_ constant, invoke in_pcbconnect_setup()
1331                  * to do the heavy lifting.  Once a port is selected, we
1332                  * commit the binding back to the socket; we also commit the
1333                  * binding of the address if in jail.
1334                  *
1335                  * If we already have a valid binding and we're not
1336                  * requesting a destination address rewrite, use a fast path.
1337                  */
1338                 if (inp->inp_laddr.s_addr == INADDR_ANY ||
1339                     inp->inp_lport == 0 ||
1340                     sin->sin_addr.s_addr == INADDR_ANY ||
1341                     sin->sin_addr.s_addr == INADDR_BROADCAST) {
1342                         INP_HASH_LOCK_ASSERT(pcbinfo);
1343                         error = in_pcbconnect_setup(inp, addr, &laddr.s_addr,
1344                             &lport, &faddr.s_addr, &fport, NULL,
1345                             td->td_ucred);
1346                         if (error)
1347                                 goto release;
1348
1349                         /*
1350                          * XXXRW: Why not commit the port if the address is
1351                          * !INADDR_ANY?
1352                          */
1353                         /* Commit the local port if newly assigned. */
1354                         if (inp->inp_laddr.s_addr == INADDR_ANY &&
1355                             inp->inp_lport == 0) {
1356                                 INP_WLOCK_ASSERT(inp);
1357                                 INP_HASH_WLOCK_ASSERT(pcbinfo);
1358                                 /*
1359                                  * Remember addr if jailed, to prevent
1360                                  * rebinding.
1361                                  */
1362                                 if (prison_flag(td->td_ucred, PR_IP4))
1363                                         inp->inp_laddr = laddr;
1364                                 inp->inp_lport = lport;
1365                                 if (in_pcbinshash(inp) != 0) {
1366                                         inp->inp_lport = 0;
1367                                         error = EAGAIN;
1368                                         goto release;
1369                                 }
1370                                 inp->inp_flags |= INP_ANONPORT;
1371                         }
1372                 } else {
1373                         faddr = sin->sin_addr;
1374                         fport = sin->sin_port;
1375                 }
1376         } else {
1377                 INP_LOCK_ASSERT(inp);
1378                 faddr = inp->inp_faddr;
1379                 fport = inp->inp_fport;
1380                 if (faddr.s_addr == INADDR_ANY) {
1381                         error = ENOTCONN;
1382                         goto release;
1383                 }
1384         }
1385
1386         /*
1387          * Calculate data length and get a mbuf for UDP, IP, and possible
1388          * link-layer headers.  Immediate slide the data pointer back forward
1389          * since we won't use that space at this layer.
1390          */
1391         M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_NOWAIT);
1392         if (m == NULL) {
1393                 error = ENOBUFS;
1394                 goto release;
1395         }
1396         m->m_data += max_linkhdr;
1397         m->m_len -= max_linkhdr;
1398         m->m_pkthdr.len -= max_linkhdr;
1399
1400         /*
1401          * Fill in mbuf with extended UDP header and addresses and length put
1402          * into network format.
1403          */
1404         ui = mtod(m, struct udpiphdr *);
1405         bzero(ui->ui_x1, sizeof(ui->ui_x1));    /* XXX still needed? */
1406         ui->ui_pr = pr;
1407         ui->ui_src = laddr;
1408         ui->ui_dst = faddr;
1409         ui->ui_sport = lport;
1410         ui->ui_dport = fport;
1411         ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr));
1412         if (pr == IPPROTO_UDPLITE) {
1413                 struct udpcb *up;
1414                 uint16_t plen;
1415
1416                 up = intoudpcb(inp);
1417                 cscov = up->u_txcslen;
1418                 plen = (u_short)len + sizeof(struct udphdr);
1419                 if (cscov >= plen)
1420                         cscov = 0;
1421                 ui->ui_len = htons(plen);
1422                 ui->ui_ulen = htons(cscov);
1423                 /*
1424                  * For UDP-Lite, checksum coverage length of zero means
1425                  * the entire UDPLite packet is covered by the checksum.
1426                  */
1427                 cscov_partial = (cscov == 0) ? 0 : 1;
1428         } else
1429                 ui->ui_v = IPVERSION << 4;
1430
1431         /*
1432          * Set the Don't Fragment bit in the IP header.
1433          */
1434         if (inp->inp_flags & INP_DONTFRAG) {
1435                 struct ip *ip;
1436
1437                 ip = (struct ip *)&ui->ui_i;
1438                 ip->ip_off |= htons(IP_DF);
1439         }
1440
1441         ipflags = 0;
1442         if (inp->inp_socket->so_options & SO_DONTROUTE)
1443                 ipflags |= IP_ROUTETOIF;
1444         if (inp->inp_socket->so_options & SO_BROADCAST)
1445                 ipflags |= IP_ALLOWBROADCAST;
1446         if (inp->inp_flags & INP_ONESBCAST)
1447                 ipflags |= IP_SENDONES;
1448
1449 #ifdef MAC
1450         mac_inpcb_create_mbuf(inp, m);
1451 #endif
1452
1453         /*
1454          * Set up checksum and output datagram.
1455          */
1456         ui->ui_sum = 0;
1457         if (pr == IPPROTO_UDPLITE) {
1458                 if (inp->inp_flags & INP_ONESBCAST)
1459                         faddr.s_addr = INADDR_BROADCAST;
1460                 if (cscov_partial) {
1461                         if ((ui->ui_sum = in_cksum(m, sizeof(struct ip) + cscov)) == 0)
1462                                 ui->ui_sum = 0xffff;
1463                 } else {
1464                         if ((ui->ui_sum = in_cksum(m, sizeof(struct udpiphdr) + len)) == 0)
1465                                 ui->ui_sum = 0xffff;
1466                 }
1467         } else if (V_udp_cksum) {
1468                 if (inp->inp_flags & INP_ONESBCAST)
1469                         faddr.s_addr = INADDR_BROADCAST;
1470                 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr,
1471                     htons((u_short)len + sizeof(struct udphdr) + pr));
1472                 m->m_pkthdr.csum_flags = CSUM_UDP;
1473                 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
1474         }
1475         ((struct ip *)ui)->ip_len = htons(sizeof(struct udpiphdr) + len);
1476         ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl;    /* XXX */
1477         ((struct ip *)ui)->ip_tos = tos;                /* XXX */
1478         UDPSTAT_INC(udps_opackets);
1479
1480         /*
1481          * Setup flowid / RSS information for outbound socket.
1482          *
1483          * Once the UDP code decides to set a flowid some other way,
1484          * this allows the flowid to be overridden by userland.
1485          */
1486         if (flowtype != M_HASHTYPE_NONE) {
1487                 m->m_pkthdr.flowid = flowid;
1488                 M_HASHTYPE_SET(m, flowtype);
1489 #ifdef  RSS
1490         } else {
1491                 uint32_t hash_val, hash_type;
1492                 /*
1493                  * Calculate an appropriate RSS hash for UDP and
1494                  * UDP Lite.
1495                  *
1496                  * The called function will take care of figuring out
1497                  * whether a 2-tuple or 4-tuple hash is required based
1498                  * on the currently configured scheme.
1499                  *
1500                  * Later later on connected socket values should be
1501                  * cached in the inpcb and reused, rather than constantly
1502                  * re-calculating it.
1503                  *
1504                  * UDP Lite is a different protocol number and will
1505                  * likely end up being hashed as a 2-tuple until
1506                  * RSS / NICs grow UDP Lite protocol awareness.
1507                  */
1508                 if (rss_proto_software_hash_v4(faddr, laddr, fport, lport,
1509                     pr, &hash_val, &hash_type) == 0) {
1510                         m->m_pkthdr.flowid = hash_val;
1511                         M_HASHTYPE_SET(m, hash_type);
1512                 }
1513 #endif
1514         }
1515
1516 #ifdef  RSS
1517         /*
1518          * Don't override with the inp cached flowid value.
1519          *
1520          * Depending upon the kind of send being done, the inp
1521          * flowid/flowtype values may actually not be appropriate
1522          * for this particular socket send.
1523          *
1524          * We should either leave the flowid at zero (which is what is
1525          * currently done) or set it to some software generated
1526          * hash value based on the packet contents.
1527          */
1528         ipflags |= IP_NODEFAULTFLOWID;
1529 #endif  /* RSS */
1530
1531         if (unlock_udbinfo == UH_WLOCKED)
1532                 INP_HASH_WUNLOCK(pcbinfo);
1533         else if (unlock_udbinfo == UH_RLOCKED)
1534                 INP_HASH_RUNLOCK(pcbinfo);
1535         UDP_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1536         error = ip_output(m, inp->inp_options,
1537             (unlock_inp == UH_WLOCKED ? &inp->inp_route : NULL), ipflags,
1538             inp->inp_moptions, inp);
1539         if (unlock_inp == UH_WLOCKED)
1540                 INP_WUNLOCK(inp);
1541         else
1542                 INP_RUNLOCK(inp);
1543         return (error);
1544
1545 release:
1546         if (unlock_udbinfo == UH_WLOCKED) {
1547                 KASSERT(unlock_inp == UH_WLOCKED,
1548                     ("%s: excl udbinfo lock, shared inp lock", __func__));
1549                 INP_HASH_WUNLOCK(pcbinfo);
1550                 INP_WUNLOCK(inp);
1551         } else if (unlock_udbinfo == UH_RLOCKED) {
1552                 KASSERT(unlock_inp == UH_RLOCKED,
1553                     ("%s: shared udbinfo lock, excl inp lock", __func__));
1554                 INP_HASH_RUNLOCK(pcbinfo);
1555                 INP_RUNLOCK(inp);
1556         } else if (unlock_inp == UH_WLOCKED)
1557                 INP_WUNLOCK(inp);
1558         else
1559                 INP_RUNLOCK(inp);
1560         m_freem(m);
1561         return (error);
1562 }
1563
1564 static void
1565 udp_abort(struct socket *so)
1566 {
1567         struct inpcb *inp;
1568         struct inpcbinfo *pcbinfo;
1569
1570         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1571         inp = sotoinpcb(so);
1572         KASSERT(inp != NULL, ("udp_abort: inp == NULL"));
1573         INP_WLOCK(inp);
1574         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1575                 INP_HASH_WLOCK(pcbinfo);
1576                 in_pcbdisconnect(inp);
1577                 inp->inp_laddr.s_addr = INADDR_ANY;
1578                 INP_HASH_WUNLOCK(pcbinfo);
1579                 soisdisconnected(so);
1580         }
1581         INP_WUNLOCK(inp);
1582 }
1583
1584 static int
1585 udp_attach(struct socket *so, int proto, struct thread *td)
1586 {
1587         struct inpcb *inp;
1588         struct inpcbinfo *pcbinfo;
1589         int error;
1590
1591         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1592         inp = sotoinpcb(so);
1593         KASSERT(inp == NULL, ("udp_attach: inp != NULL"));
1594         error = soreserve(so, udp_sendspace, udp_recvspace);
1595         if (error)
1596                 return (error);
1597         INP_INFO_WLOCK(pcbinfo);
1598         error = in_pcballoc(so, pcbinfo);
1599         if (error) {
1600                 INP_INFO_WUNLOCK(pcbinfo);
1601                 return (error);
1602         }
1603
1604         inp = sotoinpcb(so);
1605         inp->inp_vflag |= INP_IPV4;
1606         inp->inp_ip_ttl = V_ip_defttl;
1607
1608         error = udp_newudpcb(inp);
1609         if (error) {
1610                 in_pcbdetach(inp);
1611                 in_pcbfree(inp);
1612                 INP_INFO_WUNLOCK(pcbinfo);
1613                 return (error);
1614         }
1615
1616         INP_WUNLOCK(inp);
1617         INP_INFO_WUNLOCK(pcbinfo);
1618         return (0);
1619 }
1620 #endif /* INET */
1621
1622 int
1623 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f, udp_tun_icmp_t i, void *ctx)
1624 {
1625         struct inpcb *inp;
1626         struct udpcb *up;
1627
1628         KASSERT(so->so_type == SOCK_DGRAM,
1629             ("udp_set_kernel_tunneling: !dgram"));
1630         inp = sotoinpcb(so);
1631         KASSERT(inp != NULL, ("udp_set_kernel_tunneling: inp == NULL"));
1632         INP_WLOCK(inp);
1633         up = intoudpcb(inp);
1634         if ((up->u_tun_func != NULL) ||
1635             (up->u_icmp_func != NULL)) {
1636                 INP_WUNLOCK(inp);
1637                 return (EBUSY);
1638         }
1639         up->u_tun_func = f;
1640         up->u_icmp_func = i;
1641         up->u_tun_ctx = ctx;
1642         INP_WUNLOCK(inp);
1643         return (0);
1644 }
1645
1646 #ifdef INET
1647 static int
1648 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1649 {
1650         struct inpcb *inp;
1651         struct inpcbinfo *pcbinfo;
1652         int error;
1653
1654         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1655         inp = sotoinpcb(so);
1656         KASSERT(inp != NULL, ("udp_bind: inp == NULL"));
1657         INP_WLOCK(inp);
1658         INP_HASH_WLOCK(pcbinfo);
1659         error = in_pcbbind(inp, nam, td->td_ucred);
1660         INP_HASH_WUNLOCK(pcbinfo);
1661         INP_WUNLOCK(inp);
1662         return (error);
1663 }
1664
1665 static void
1666 udp_close(struct socket *so)
1667 {
1668         struct inpcb *inp;
1669         struct inpcbinfo *pcbinfo;
1670
1671         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1672         inp = sotoinpcb(so);
1673         KASSERT(inp != NULL, ("udp_close: inp == NULL"));
1674         INP_WLOCK(inp);
1675         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1676                 INP_HASH_WLOCK(pcbinfo);
1677                 in_pcbdisconnect(inp);
1678                 inp->inp_laddr.s_addr = INADDR_ANY;
1679                 INP_HASH_WUNLOCK(pcbinfo);
1680                 soisdisconnected(so);
1681         }
1682         INP_WUNLOCK(inp);
1683 }
1684
1685 static int
1686 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1687 {
1688         struct inpcb *inp;
1689         struct inpcbinfo *pcbinfo;
1690         struct sockaddr_in *sin;
1691         int error;
1692
1693         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1694         inp = sotoinpcb(so);
1695         KASSERT(inp != NULL, ("udp_connect: inp == NULL"));
1696         INP_WLOCK(inp);
1697         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1698                 INP_WUNLOCK(inp);
1699                 return (EISCONN);
1700         }
1701         sin = (struct sockaddr_in *)nam;
1702         error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1703         if (error != 0) {
1704                 INP_WUNLOCK(inp);
1705                 return (error);
1706         }
1707         INP_HASH_WLOCK(pcbinfo);
1708         error = in_pcbconnect(inp, nam, td->td_ucred);
1709         INP_HASH_WUNLOCK(pcbinfo);
1710         if (error == 0)
1711                 soisconnected(so);
1712         INP_WUNLOCK(inp);
1713         return (error);
1714 }
1715
1716 static void
1717 udp_detach(struct socket *so)
1718 {
1719         struct inpcb *inp;
1720         struct inpcbinfo *pcbinfo;
1721         struct udpcb *up;
1722
1723         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1724         inp = sotoinpcb(so);
1725         KASSERT(inp != NULL, ("udp_detach: inp == NULL"));
1726         KASSERT(inp->inp_faddr.s_addr == INADDR_ANY,
1727             ("udp_detach: not disconnected"));
1728         INP_INFO_WLOCK(pcbinfo);
1729         INP_WLOCK(inp);
1730         up = intoudpcb(inp);
1731         KASSERT(up != NULL, ("%s: up == NULL", __func__));
1732         inp->inp_ppcb = NULL;
1733         in_pcbdetach(inp);
1734         in_pcbfree(inp);
1735         INP_INFO_WUNLOCK(pcbinfo);
1736         udp_discardcb(up);
1737 }
1738
1739 static int
1740 udp_disconnect(struct socket *so)
1741 {
1742         struct inpcb *inp;
1743         struct inpcbinfo *pcbinfo;
1744
1745         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1746         inp = sotoinpcb(so);
1747         KASSERT(inp != NULL, ("udp_disconnect: inp == NULL"));
1748         INP_WLOCK(inp);
1749         if (inp->inp_faddr.s_addr == INADDR_ANY) {
1750                 INP_WUNLOCK(inp);
1751                 return (ENOTCONN);
1752         }
1753         INP_HASH_WLOCK(pcbinfo);
1754         in_pcbdisconnect(inp);
1755         inp->inp_laddr.s_addr = INADDR_ANY;
1756         INP_HASH_WUNLOCK(pcbinfo);
1757         SOCK_LOCK(so);
1758         so->so_state &= ~SS_ISCONNECTED;                /* XXX */
1759         SOCK_UNLOCK(so);
1760         INP_WUNLOCK(inp);
1761         return (0);
1762 }
1763
1764 static int
1765 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
1766     struct mbuf *control, struct thread *td)
1767 {
1768         struct inpcb *inp;
1769
1770         inp = sotoinpcb(so);
1771         KASSERT(inp != NULL, ("udp_send: inp == NULL"));
1772         return (udp_output(inp, m, addr, control, td));
1773 }
1774 #endif /* INET */
1775
1776 int
1777 udp_shutdown(struct socket *so)
1778 {
1779         struct inpcb *inp;
1780
1781         inp = sotoinpcb(so);
1782         KASSERT(inp != NULL, ("udp_shutdown: inp == NULL"));
1783         INP_WLOCK(inp);
1784         socantsendmore(so);
1785         INP_WUNLOCK(inp);
1786         return (0);
1787 }
1788
1789 #ifdef INET
1790 struct pr_usrreqs udp_usrreqs = {
1791         .pru_abort =            udp_abort,
1792         .pru_attach =           udp_attach,
1793         .pru_bind =             udp_bind,
1794         .pru_connect =          udp_connect,
1795         .pru_control =          in_control,
1796         .pru_detach =           udp_detach,
1797         .pru_disconnect =       udp_disconnect,
1798         .pru_peeraddr =         in_getpeeraddr,
1799         .pru_send =             udp_send,
1800         .pru_soreceive =        soreceive_dgram,
1801         .pru_sosend =           sosend_dgram,
1802         .pru_shutdown =         udp_shutdown,
1803         .pru_sockaddr =         in_getsockaddr,
1804         .pru_sosetlabel =       in_pcbsosetlabel,
1805         .pru_close =            udp_close,
1806 };
1807 #endif /* INET */