ReactOS 0.4.15-dev-8096-ga0eec98
ip6.c
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1/*
2 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without modification,
6 * are permitted provided that the following conditions are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright notice,
9 * this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright notice,
11 * this list of conditions and the following disclaimer in the documentation
12 * and/or other materials provided with the distribution.
13 * 3. The name of the author may not be used to endorse or promote products
14 * derived from this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
17 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
18 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
19 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
21 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
22 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
23 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
24 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
25 * OF SUCH DAMAGE.
26 *
27 * This file is part of the lwIP TCP/IP stack.
28 *
29 * Author: Adam Dunkels <adam@sics.se>
30 *
31 */
32
33
34
35/* ip.c
36 *
37 * This is the code for the IP layer for IPv6.
38 *
39 */
40
41
42#include "lwip/opt.h"
43
44#include "lwip/def.h"
45#include "lwip/mem.h"
46#include "lwip/ip.h"
47#include "lwip/inet.h"
48#include "lwip/netif.h"
49#include "lwip/icmp.h"
50#include "lwip/udp.h"
51#include "lwip/tcp_impl.h"
52
53#include "lwip/stats.h"
54
55#include "arch/perf.h"
56
57/* ip_init:
58 *
59 * Initializes the IP layer.
60 */
61
62void
64{
65}
66
67/* ip_route:
68 *
69 * Finds the appropriate network interface for a given IP address. It searches the
70 * list of network interfaces linearly. A match is found if the masked IP address of
71 * the network interface equals the masked IP address given to the function.
72 */
73
74struct netif *
76{
77 struct netif *netif;
78
79 for(netif = netif_list; netif != NULL; netif = netif->next) {
81 return netif;
82 }
83 }
84
85 return netif_default;
86}
87
88/* ip_forward:
89 *
90 * Forwards an IP packet. It finds an appropriate route for the packet, decrements
91 * the TTL value of the packet, adjusts the checksum and outputs the packet on the
92 * appropriate interface.
93 */
94
95static void
96ip_forward(struct pbuf *p, struct ip_hdr *iphdr)
97{
98 struct netif *netif;
99
101
102 if ((netif = ip_route((struct ip_addr *)&(iphdr->dest))) == NULL) {
103
104 LWIP_DEBUGF(IP_DEBUG, ("ip_input: no forwarding route found for "));
105#if IP_DEBUG
106 ip_addr_debug_print(IP_DEBUG, ((struct ip_addr *)&(iphdr->dest)));
107#endif /* IP_DEBUG */
108 LWIP_DEBUGF(IP_DEBUG, ("\n"));
109 pbuf_free(p);
110 return;
111 }
112 /* Decrement TTL and send ICMP if ttl == 0. */
113 if (--iphdr->hoplim == 0) {
114#if LWIP_ICMP
115 /* Don't send ICMP messages in response to ICMP messages */
116 if (iphdr->nexthdr != IP_PROTO_ICMP) {
117 icmp_time_exceeded(p, ICMP_TE_TTL);
118 }
119#endif /* LWIP_ICMP */
120 pbuf_free(p);
121 return;
122 }
123
124 /* Incremental update of the IP checksum. */
125 /* if (iphdr->chksum >= htons(0xffff - 0x100)) {
126 iphdr->chksum += htons(0x100) + 1;
127 } else {
128 iphdr->chksum += htons(0x100);
129 }*/
130
131
132 LWIP_DEBUGF(IP_DEBUG, ("ip_forward: forwarding packet to "));
133#if IP_DEBUG
134 ip_addr_debug_print(IP_DEBUG, ((struct ip_addr *)&(iphdr->dest)));
135#endif /* IP_DEBUG */
136 LWIP_DEBUGF(IP_DEBUG, ("\n"));
137
138 IP_STATS_INC(ip.fw);
139 IP_STATS_INC(ip.xmit);
140
141 PERF_STOP("ip_forward");
142
143 netif->output(netif, p, (struct ip_addr *)&(iphdr->dest));
144}
145
146/* ip_input:
147 *
148 * This function is called by the network interface device driver when an IP packet is
149 * received. The function does the basic checks of the IP header such as packet size
150 * being at least larger than the header size etc. If the packet was not destined for
151 * us, the packet is forwarded (using ip_forward). The IP checksum is always checked.
152 *
153 * Finally, the packet is sent to the upper layer protocol input function.
154 */
155
156void
157ip_input(struct pbuf *p, struct netif *inp) {
158 struct ip_hdr *iphdr;
159 struct netif *netif;
160
161
163
164#if IP_DEBUG
166#endif /* IP_DEBUG */
167
168
169 IP_STATS_INC(ip.recv);
170
171 /* identify the IP header */
172 iphdr = p->payload;
173
174
175 if (iphdr->v != 6) {
176 LWIP_DEBUGF(IP_DEBUG, ("IP packet dropped due to bad version number\n"));
177#if IP_DEBUG
179#endif /* IP_DEBUG */
180 pbuf_free(p);
181 IP_STATS_INC(ip.err);
182 IP_STATS_INC(ip.drop);
183 return;
184 }
185
186 /* is this packet for us? */
187 for(netif = netif_list; netif != NULL; netif = netif->next) {
188#if IP_DEBUG
189 LWIP_DEBUGF(IP_DEBUG, ("ip_input: iphdr->dest "));
190 ip_addr_debug_print(IP_DEBUG, ((struct ip_addr *)&(iphdr->dest)));
191 LWIP_DEBUGF(IP_DEBUG, ("netif->ip_addr "));
192 ip_addr_debug_print(IP_DEBUG, ((struct ip_addr *)&(iphdr->dest)));
193 LWIP_DEBUGF(IP_DEBUG, ("\n"));
194#endif /* IP_DEBUG */
195 if (ip_addr_cmp(&(iphdr->dest), &(netif->ip_addr))) {
196 break;
197 }
198 }
199
200
201 if (netif == NULL) {
202 /* packet not for us, route or discard */
203#if IP_FORWARD
204 ip_forward(p, iphdr);
205#endif
206 pbuf_free(p);
207 return;
208 }
209
210 pbuf_realloc(p, IP_HLEN + ntohs(iphdr->len));
211
212 /* send to upper layers */
213#if IP_DEBUG
214 /* LWIP_DEBUGF("ip_input: \n");
215 ip_debug_print(p);
216 LWIP_DEBUGF("ip_input: p->len %"U16_F" p->tot_len %"U16_F"\n", p->len, p->tot_len);*/
217#endif /* IP_DEBUG */
218
219 if(pbuf_header(p, -IP_HLEN)) {
220 LWIP_ASSERT("Can't move over header in packet", 0);
221 return;
222 }
223
224 switch (iphdr->nexthdr) {
225 case IP_PROTO_UDP:
226 udp_input(p, inp);
227 break;
228 case IP_PROTO_TCP:
229 tcp_input(p, inp);
230 break;
231#if LWIP_ICMP
232 case IP_PROTO_ICMP:
233 icmp_input(p, inp);
234 break;
235#endif /* LWIP_ICMP */
236 default:
237#if LWIP_ICMP
238 /* send ICMP destination protocol unreachable */
239 icmp_dest_unreach(p, ICMP_DUR_PROTO);
240#endif /* LWIP_ICMP */
241 pbuf_free(p);
242 LWIP_DEBUGF(IP_DEBUG, ("Unsupported transport protocol %"U16_F"\n",
243 iphdr->nexthdr));
244
245 IP_STATS_INC(ip.proterr);
246 IP_STATS_INC(ip.drop);
247 }
248 PERF_STOP("ip_input");
249}
250
251
252/* ip_output_if:
253 *
254 * Sends an IP packet on a network interface. This function constructs the IP header
255 * and calculates the IP header checksum. If the source IP address is NULL,
256 * the IP address of the outgoing network interface is filled in as source address.
257 */
258
259err_t
260ip_output_if (struct pbuf *p, struct ip_addr *src, struct ip_addr *dest,
261 u8_t ttl,
262 u8_t proto, struct netif *netif)
263{
264 struct ip_hdr *iphdr;
265
267
268 LWIP_DEBUGF(IP_DEBUG, ("len %"U16_F" tot_len %"U16_F"\n", p->len, p->tot_len));
269 if (pbuf_header(p, IP_HLEN)) {
270 LWIP_DEBUGF(IP_DEBUG, ("ip_output: not enough room for IP header in pbuf\n"));
271 IP_STATS_INC(ip.err);
272
273 return ERR_BUF;
274 }
275 LWIP_DEBUGF(IP_DEBUG, ("len %"U16_F" tot_len %"U16_F"\n", p->len, p->tot_len));
276
277 iphdr = p->payload;
278
279
280 if (dest != IP_HDRINCL) {
281 LWIP_DEBUGF(IP_DEBUG, ("!IP_HDRLINCL\n"));
282 iphdr->hoplim = ttl;
283 iphdr->nexthdr = proto;
284 iphdr->len = htons(p->tot_len - IP_HLEN);
285 ip_addr_set(&(iphdr->dest), dest);
286
287 iphdr->v = 6;
288
289 if (ip_addr_isany(src)) {
290 ip_addr_set(&(iphdr->src), &(netif->ip_addr));
291 } else {
292 ip_addr_set(&(iphdr->src), src);
293 }
294
295 } else {
296 dest = &(iphdr->dest);
297 }
298
299 IP_STATS_INC(ip.xmit);
300
301 LWIP_DEBUGF(IP_DEBUG, ("ip_output_if: %c%c (len %"U16_F")\n", netif->name[0], netif->name[1], p->tot_len));
302#if IP_DEBUG
304#endif /* IP_DEBUG */
305
306 PERF_STOP("ip_output_if");
307 return netif->output(netif, p, dest);
308}
309
310/* ip_output:
311 *
312 * Simple interface to ip_output_if. It finds the outgoing network interface and
313 * calls upon ip_output_if to do the actual work.
314 */
315
316err_t
317ip_output(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest,
318 u8_t ttl, u8_t proto)
319{
320 struct netif *netif;
321 if ((netif = ip_route(dest)) == NULL) {
322 LWIP_DEBUGF(IP_DEBUG, ("ip_output: No route to 0x%"X32_F"\n", dest->addr));
323 IP_STATS_INC(ip.rterr);
324 return ERR_RTE;
325 }
326
327 return ip_output_if (p, src, dest, ttl, proto, netif);
328}
329
330#if LWIP_NETIF_HWADDRHINT
331err_t
332ip_output_hinted(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest,
333 u8_t ttl, u8_t tos, u8_t proto, u8_t *addr_hint)
334{
335 struct netif *netif;
336 err_t err;
337
338 if ((netif = ip_route(dest)) == NULL) {
339 LWIP_DEBUGF(IP_DEBUG, ("ip_output: No route to 0x%"X32_F"\n", dest->addr));
340 IP_STATS_INC(ip.rterr);
341 return ERR_RTE;
342 }
343
344 LWIP_NETIF_HWADDRHINT(netif, addr_hint);
345 err = ip_output_if(p, src, dest, ttl, tos, proto, netif);
347
348 return err;
349}
350#endif /* LWIP_NETIF_HWADDRHINT*/
351
352#if IP_DEBUG
353void
354ip_debug_print(struct pbuf *p)
355{
356 struct ip_hdr *iphdr = p->payload;
357
358 LWIP_DEBUGF(IP_DEBUG, ("IP header:\n"));
359 LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
360 LWIP_DEBUGF(IP_DEBUG, ("|%2"S16_F" | %"X16_F"%"X16_F" | %"X16_F"%"X16_F" | (v, traffic class, flow label)\n",
361 iphdr->v,
362 iphdr->tclass1, iphdr->tclass2,
363 iphdr->flow1, iphdr->flow2));
364 LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
365 LWIP_DEBUGF(IP_DEBUG, ("| %5"U16_F" | %2"U16_F" | %2"U16_F" | (len, nexthdr, hoplim)\n",
366 ntohs(iphdr->len),
367 iphdr->nexthdr,
368 iphdr->hoplim));
369 LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
370 LWIP_DEBUGF(IP_DEBUG, ("| %4"X32_F" | %4"X32_F" | (src)\n",
371 (ntohl(iphdr->src.addr[0]) >> 16) & 0xffff,
372 ntohl(iphdr->src.addr[0]) & 0xffff));
373 LWIP_DEBUGF(IP_DEBUG, ("| %4"X32_F" | %4"X32_F" | (src)\n",
374 (ntohl(iphdr->src.addr[1]) >> 16) & 0xffff,
375 ntohl(iphdr->src.addr[1]) & 0xffff));
376 LWIP_DEBUGF(IP_DEBUG, ("| %4"X32_F" | %4"X32_F" | (src)\n",
377 (ntohl(iphdr->src.addr[2]) >> 16) & 0xffff,
378 ntohl(iphdr->src.addr[2]) & 0xffff));
379 LWIP_DEBUGF(IP_DEBUG, ("| %4"X32_F" | %4"X32_F" | (src)\n",
380 (ntohl(iphdr->src.addr[3]) >> 16) & 0xffff,
381 ntohl(iphdr->src.addr[3]) & 0xffff));
382 LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
383 LWIP_DEBUGF(IP_DEBUG, ("| %4"X32_F" | %4"X32_F" | (dest)\n",
384 (ntohl(iphdr->dest.addr[0]) >> 16) & 0xffff,
385 ntohl(iphdr->dest.addr[0]) & 0xffff));
386 LWIP_DEBUGF(IP_DEBUG, ("| %4"X32_F" | %4"X32_F" | (dest)\n",
387 (ntohl(iphdr->dest.addr[1]) >> 16) & 0xffff,
388 ntohl(iphdr->dest.addr[1]) & 0xffff));
389 LWIP_DEBUGF(IP_DEBUG, ("| %4"X32_F" | %4"X32_F" | (dest)\n",
390 (ntohl(iphdr->dest.addr[2]) >> 16) & 0xffff,
391 ntohl(iphdr->dest.addr[2]) & 0xffff));
392 LWIP_DEBUGF(IP_DEBUG, ("| %4"X32_F" | %4"X32_F" | (dest)\n",
393 (ntohl(iphdr->dest.addr[3]) >> 16) & 0xffff,
394 ntohl(iphdr->dest.addr[3]) & 0xffff));
395 LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
396}
397#endif /* IP_DEBUG */
#define NULL
Definition: types.h:112
#define X16_F
Definition: cc.h:38
#define U16_F
Definition: cc.h:36
#define S16_F
Definition: cc.h:37
#define X32_F
Definition: cc.h:41
unsigned char u8_t
Definition: cc.h:23
err_t ip_output(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest, u8_t ttl, u8_t proto)
Definition: ip6.c:317
void ip_init(void)
Definition: ip6.c:63
err_t ip_output_if(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest, u8_t ttl, u8_t proto, struct netif *netif)
Definition: ip6.c:260
static void ip_forward(struct pbuf *p, struct ip_hdr *iphdr)
Definition: ip6.c:96
struct netif * ip_route(struct ip_addr *dest)
Definition: ip6.c:75
void ip_input(struct pbuf *p, struct netif *inp)
Definition: ip6.c:157
#define IP_HDRINCL
Definition: ip.h:64
#define IP_PROTO_TCP
Definition: ip.h:56
#define IP_PROTO_UDP
Definition: ip.h:54
#define ip_debug_print(p)
Definition: ip.h:214
#define IP_PROTO_ICMP
Definition: ip.h:52
#define IP_HLEN
Definition: ip.h:50
#define LWIP_DEBUGF(debug, message)
Definition: debug.h:95
#define LWIP_ASSERT(message, assertion)
Definition: debug.h:66
#define ERR_RTE
Definition: err.h:56
#define ERR_BUF
Definition: err.h:54
s8_t err_t
Definition: err.h:47
GLenum src
Definition: glext.h:6340
GLfloat GLfloat p
Definition: glext.h:8902
#define IP_DEBUG
Definition: lwipopts.h:135
#define LWIP_NETIF_HWADDRHINT
Definition: lwipopts.h:87
#define ip_addr_cmp(addr1, addr2)
Definition: ip_addr.h:198
#define ip_addr_isany(addr1)
Definition: ip_addr.h:200
#define ip_addr_netcmp(addr1, addr2, mask)
Definition: ip_addr.h:194
#define ip_addr_set(dest, src)
Definition: ip_addr.h:164
#define ip_addr_debug_print(debug, ipaddr)
Definition: ip_addr.h:212
@ ICMP_TE_TTL
Definition: icmp.h:66
@ ICMP_DUR_PROTO
Definition: icmp.h:59
#define htons(x)
Definition: module.h:215
#define ntohl(x)
Definition: module.h:205
#define ntohs(x)
Definition: module.h:210
static char * dest
Definition: rtl.c:135
struct netif * netif_list
Definition: netif.c:75
struct netif * netif_default
Definition: netif.c:76
u8_t pbuf_header(struct pbuf *p, s16_t header_size_increment)
Definition: pbuf.c:511
void pbuf_realloc(struct pbuf *p, u16_t new_len)
Definition: pbuf.c:430
u8_t pbuf_free(struct pbuf *p)
Definition: pbuf.c:618
#define PERF_START
Definition: perf.h:3
#define PERF_STOP
Definition: perf.h:4
#define err(...)
#define IP_STATS_INC(x)
Definition: stats.h:203
Definition: ip.h:116
u8_t v
Definition: ip.h:86
u8_t flow1
Definition: ip.h:87
u16_t len
Definition: ip.h:93
struct ip_addr src dest
Definition: ip.h:96
u8_t hoplim
Definition: ip.h:95
u16_t flow2
Definition: ip.h:92
u8_t nexthdr
Definition: ip.h:94
u8_t tclass2
Definition: ip.h:87
u8_t tclass1
Definition: ip.h:86
Definition: dhcpd.h:62
Definition: netif.h:136
char name[2]
Definition: netif.h:194
ip_addr_t netmask
Definition: netif.h:142
netif_output_fn output
Definition: netif.h:151
ip_addr_t ip_addr
Definition: netif.h:141
struct netif * next
Definition: netif.h:138
Definition: pbuf.h:79