2 * Copyright (c) 1992 Regents of the University of California.
5 * This software was developed by the Computer Systems Engineering group
6 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
7 * contributed to Berkeley.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. 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.
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
35 * The send and receive functions were originally implemented in udp.c and
36 * moved here. Also it is likely some more cleanup can be done, especially
37 * once we will implement the support for tcp.
40 #include <sys/cdefs.h>
41 #include <sys/param.h>
42 #include <sys/socket.h>
43 #include <sys/queue.h>
48 #include <netinet/in.h>
49 #include <netinet/if_ether.h>
50 #include <netinet/in_systm.h>
52 #include <netinet/ip.h>
53 #include <netinet/ip_var.h>
54 #include <netinet/udp.h>
55 #include <netinet/udp_var.h>
60 typedef STAILQ_HEAD(ipqueue, ip_queue) ip_queue_t;
64 STAILQ_ENTRY(ip_queue) ipq_next;
68 * Fragment re-assembly queue.
71 struct in_addr ip_src;
72 struct in_addr ip_dst;
80 STAILQ_ENTRY(ip_reasm) ip_next;
83 STAILQ_HEAD(ire_list, ip_reasm) ire_list = STAILQ_HEAD_INITIALIZER(ire_list);
85 /* Caller must leave room for ethernet and ip headers in front!! */
87 sendip(struct iodesc *d, void *pkt, size_t len, uint8_t proto)
95 printf("sendip: proto: %x d=%p called.\n", proto, (void *)d);
97 printf("saddr: %s:%d",
98 inet_ntoa(d->myip), ntohs(d->myport));
99 printf(" daddr: %s:%d\n",
100 inet_ntoa(d->destip), ntohs(d->destport));
105 ip = (struct ip *)pkt - 1;
108 bzero(ip, sizeof(*ip));
110 ip->ip_v = IPVERSION; /* half-char */
111 ip->ip_hl = sizeof(*ip) >> 2; /* half-char */
112 ip->ip_len = htons(len);
113 ip->ip_p = proto; /* char */
114 ip->ip_ttl = IPDEFTTL; /* char */
115 ip->ip_src = d->myip;
116 ip->ip_dst = d->destip;
117 ip->ip_sum = in_cksum(ip, sizeof(*ip)); /* short, but special */
119 if (ip->ip_dst.s_addr == INADDR_BROADCAST || ip->ip_src.s_addr == 0 ||
120 netmask == 0 || SAMENET(ip->ip_src, ip->ip_dst, netmask))
121 ea = arpwhohas(d, ip->ip_dst);
123 ea = arpwhohas(d, gateip);
125 cc = sendether(d, ip, len, ea, ETHERTYPE_IP);
129 panic("sendip: bad write (%zd != %zd)", cc, len);
130 return (cc - sizeof(*ip));
134 ip_reasm_free(struct ip_reasm *ipr)
136 struct ip_queue *ipq;
138 while ((ipq = STAILQ_FIRST(&ipr->ip_queue)) != NULL) {
139 STAILQ_REMOVE_HEAD(&ipr->ip_queue, ipq_next);
148 ip_reasm_add(struct ip_reasm *ipr, void *pkt, struct ip *ip)
150 struct ip_queue *ipq, *prev, *p;
152 if ((ipq = calloc(1, sizeof (*ipq))) == NULL)
159 STAILQ_FOREACH(p, &ipr->ip_queue, ipq_next) {
160 if ((ntohs(p->ipq_hdr->ip_off) & IP_OFFMASK) <
161 (ntohs(ip->ip_off) & IP_OFFMASK)) {
168 STAILQ_INSERT_AFTER(&ipr->ip_queue, prev, ipq, ipq_next);
171 STAILQ_INSERT_HEAD(&ipr->ip_queue, ipq, ipq_next);
176 * Receive a IP packet and validate it is for us.
179 readipv4(struct iodesc *d, void **pkt, void **payload, time_t tleft,
184 struct ether_header *eh;
187 uint16_t etype; /* host order */
189 struct ip_reasm *ipr;
190 struct ip_queue *ipq, *last;
194 printf("readip: called\n");
199 n = readether(d, (void **)&ptr, (void **)&ip, tleft, &etype);
200 if (n == -1 || n < sizeof(*ip) + sizeof(*uh)) {
205 /* Ethernet address checks now in readether() */
207 /* Need to respond to ARP requests. */
208 if (etype == ETHERTYPE_ARP) {
209 struct arphdr *ah = (void *)ip;
210 if (ah->ar_op == htons(ARPOP_REQUEST)) {
215 errno = EAGAIN; /* Call me again. */
219 if (etype != ETHERTYPE_IP) {
222 printf("readip: not IP. ether_type=%x\n", etype);
228 /* Check ip header */
229 if (ip->ip_v != IPVERSION || /* half char */
233 printf("readip: IP version or proto. ip_v=%d ip_p=%d\n",
241 hlen = ip->ip_hl << 2;
242 if (hlen < sizeof(*ip) ||
243 in_cksum(ip, hlen) != 0) {
246 printf("readip: short hdr or bad cksum.\n");
251 if (n < ntohs(ip->ip_len)) {
254 printf("readip: bad length %d < %d.\n",
255 (int)n, ntohs(ip->ip_len));
260 if (d->myip.s_addr && ip->ip_dst.s_addr != d->myip.s_addr) {
263 printf("readip: bad saddr %s != ", inet_ntoa(d->myip));
264 printf("%s\n", inet_ntoa(ip->ip_dst));
271 /* Unfragmented packet. */
272 if ((ntohs(ip->ip_off) & IP_MF) == 0 &&
273 (ntohs(ip->ip_off) & IP_OFFMASK) == 0) {
274 uh = (struct udphdr *)((uintptr_t)ip + sizeof (*ip));
275 /* If there were ip options, make them go away */
276 if (hlen != sizeof(*ip)) {
277 bcopy(((u_char *)ip) + hlen, uh, uh->uh_ulen - hlen);
278 ip->ip_len = htons(sizeof(*ip));
279 n -= hlen - sizeof(*ip);
282 n = (n > (ntohs(ip->ip_len) - sizeof(*ip))) ?
283 ntohs(ip->ip_len) - sizeof(*ip) : n;
285 *payload = (void *)((uintptr_t)ip + sizeof(*ip));
289 STAILQ_FOREACH(ipr, &ire_list, ip_next) {
290 if (ipr->ip_src.s_addr == ip->ip_src.s_addr &&
291 ipr->ip_dst.s_addr == ip->ip_dst.s_addr &&
292 ipr->ip_id == ip->ip_id &&
293 ipr->ip_proto == ip->ip_p)
297 /* Allocate new reassembly entry */
299 if ((ipr = calloc(1, sizeof (*ipr))) == NULL) {
304 ipr->ip_src = ip->ip_src;
305 ipr->ip_dst = ip->ip_dst;
306 ipr->ip_id = ip->ip_id;
307 ipr->ip_proto = ip->ip_p;
308 ipr->ip_ttl = MAXTTL;
309 STAILQ_INIT(&ipr->ip_queue);
310 STAILQ_INSERT_TAIL(&ire_list, ipr, ip_next);
313 if (ip_reasm_add(ipr, ptr, ip) != 0) {
314 STAILQ_REMOVE(&ire_list, ipr, ip_reasm, ip_next);
320 if ((ntohs(ip->ip_off) & IP_MF) == 0) {
321 ipr->ip_total_size = (8 * (ntohs(ip->ip_off) & IP_OFFMASK));
322 ipr->ip_total_size += n + sizeof (*ip);
323 ipr->ip_total_size += sizeof (struct ether_header);
325 ipr->ip_pkt = malloc(ipr->ip_total_size + 2);
326 if (ipr->ip_pkt == NULL) {
327 STAILQ_REMOVE(&ire_list, ipr, ip_reasm, ip_next);
334 * If we do not have re-assembly buffer ipr->ip_pkt, we are still
335 * missing fragments, so just restart the read.
337 if (ipr->ip_pkt == NULL) {
343 * Walk the packet list in reassembly queue, if we got all the
344 * fragments, build the packet.
348 STAILQ_FOREACH(ipq, &ipr->ip_queue, ipq_next) {
349 if ((ntohs(ipq->ipq_hdr->ip_off) & IP_OFFMASK) != n / 8) {
350 STAILQ_REMOVE(&ire_list, ipr, ip_reasm, ip_next);
355 n += ntohs(ipq->ipq_hdr->ip_len) - (ipq->ipq_hdr->ip_hl << 2);
358 if ((ntohs(last->ipq_hdr->ip_off) & IP_MF) != 0) {
363 ipq = STAILQ_FIRST(&ipr->ip_queue);
364 /* Fabricate ethernet header */
365 eh = (struct ether_header *)((uintptr_t)ipr->ip_pkt + 2);
366 bcopy((void *)((uintptr_t)ipq->ipq_pkt + 2), eh, sizeof (*eh));
368 /* Fabricate IP header */
369 ipr->ip_hdr = (struct ip *)((uintptr_t)eh + sizeof (*eh));
370 bcopy(ipq->ipq_hdr, ipr->ip_hdr, sizeof (*ipr->ip_hdr));
371 ipr->ip_hdr->ip_hl = sizeof (*ipr->ip_hdr) >> 2;
372 ipr->ip_hdr->ip_len = htons(n);
373 ipr->ip_hdr->ip_sum = 0;
374 ipr->ip_hdr->ip_sum = in_cksum(ipr->ip_hdr, sizeof (*ipr->ip_hdr));
377 ptr = (char *)((uintptr_t)ipr->ip_hdr + sizeof (*ipr->ip_hdr));
378 STAILQ_FOREACH(ipq, &ipr->ip_queue, ipq_next) {
382 hlen = ipq->ipq_hdr->ip_hl << 2;
383 len = ntohs(ipq->ipq_hdr->ip_len) - hlen;
384 data = (char *)((uintptr_t)ipq->ipq_hdr + hlen);
386 bcopy(data, ptr + n, len);
391 ipr->ip_pkt = NULL; /* Avoid free from ip_reasm_free() */
394 /* Clean up the reassembly list */
395 while ((ipr = STAILQ_FIRST(&ire_list)) != NULL) {
396 STAILQ_REMOVE_HEAD(&ire_list, ip_next);
403 * Receive a IP packet.
406 readip(struct iodesc *d, void **pkt, void **payload, time_t tleft,
413 while ((getsecs() - t) < tleft) {
415 ret = readipv4(d, pkt, payload, tleft, proto);
418 /* Bubble up the error if it wasn't successful */
422 /* We've exhausted tleft; timeout */