ReactOS  0.4.15-dev-1171-gab82533
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 
62 void
63 ip_init(void)
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 
74 struct netif *
76 {
77  struct netif *netif;
78 
79  for(netif = netif_list; netif != NULL; netif = netif->next) {
80  if (ip_addr_netcmp(dest, &(netif->ip_addr), &(netif->netmask))) {
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 
95 static void
96 ip_forward(struct pbuf *p, struct ip_hdr *iphdr)
97 {
98  struct netif *netif;
99 
100  PERF_START;
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 
156 void
157 ip_input(struct pbuf *p, struct netif *inp) {
158  struct ip_hdr *iphdr;
159  struct netif *netif;
160 
161 
162  PERF_START;
163 
164 #if IP_DEBUG
165  ip_debug_print(p);
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
178  ip_debug_print(p);
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 
259 err_t
260 ip_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 
266  PERF_START;
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
303  ip_debug_print(p);
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 
316 err_t
317 ip_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
331 err_t
332 ip_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
353 void
354 ip_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 X32_F
Definition: cc.h:41
struct netif * netif_list
Definition: netif.c:75
struct netif * ip_route(struct ip_addr *dest)
Definition: ip6.c:75
void ip_init(void)
Definition: ip6.c:63
#define ERR_RTE
Definition: err.h:56
#define S16_F
Definition: cc.h:37
struct netif * netif_default
Definition: netif.c:76
#define IP_PROTO_ICMP
Definition: ip.h:52
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
netif_output_fn output
Definition: netif.h:151
#define LWIP_ASSERT(message, assertion)
Definition: debug.h:66
#define ntohs(x)
Definition: module.h:208
u8_t tclass1
Definition: ip.h:86
#define PERF_START
Definition: perf.h:3
#define IP_DEBUG
Definition: opt.h:1961
#define IP_HDRINCL
Definition: ws2ipdef.h:28
#define IP_PROTO_TCP
Definition: ip.h:56
smooth NULL
Definition: ftsmooth.c:416
u8_t pbuf_free(struct pbuf *p)
Definition: pbuf.c:618
s8_t err_t
Definition: err.h:47
#define IP_HLEN
Definition: ip.h:50
#define LWIP_DEBUGF(debug, message)
Definition: debug.h:95
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
u16_t len
Definition: ip.h:93
#define U16_F
Definition: cc.h:36
struct netif * next
Definition: netif.h:138
Definition: dhcpd.h:61
Definition: pbuf.h:79
u8_t hoplim
Definition: ip.h:95
u8_t nexthdr
Definition: ip.h:94
#define X16_F
Definition: cc.h:38
#define IP_PROTO_UDP
Definition: ip.h:54
#define ip_addr_debug_print(debug, ipaddr)
Definition: ip_addr.h:212
Definition: netif.h:136
ip_addr_t ip_addr
Definition: netif.h:141
void ip_input(struct pbuf *p, struct netif *inp)
Definition: ip6.c:157
struct ip_addr src dest
Definition: ip.h:96
GLenum src
Definition: glext.h:6340
#define err(...)
u8_t tclass2
Definition: ip.h:87
#define ip_addr_set(dest, src)
Definition: ip_addr.h:164
#define ip_addr_isany(addr1)
Definition: ip_addr.h:200
Definition: ip.h:116
#define ip_addr_cmp(addr1, addr2)
Definition: ip_addr.h:198
#define ERR_BUF
Definition: err.h:54
unsigned char u8_t
Definition: cc.h:23
u8_t v
Definition: ip.h:86
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
#define IP_STATS_INC(x)
Definition: stats.h:203
char name[2]
Definition: netif.h:194
ip_addr_t netmask
Definition: netif.h:142
#define ip_debug_print(p)
Definition: ip.h:214
static char * dest
Definition: rtl.c:135
static void ip_forward(struct pbuf *p, struct ip_hdr *iphdr)
Definition: ip6.c:96
u8_t flow1
Definition: ip.h:87
GLfloat GLfloat p
Definition: glext.h:8902
#define htons(x)
Definition: module.h:213
#define ip_addr_netcmp(addr1, addr2, mask)
Definition: ip_addr.h:194
u16_t flow2
Definition: ip.h:92
#define LWIP_NETIF_HWADDRHINT
Definition: opt.h:1159
#define ntohl(x)
Definition: module.h:203