Linux preempt-rt

Check our new training course

Real-Time Linux with PREEMPT_RT

Check our new training course
with Creative Commons CC-BY-SA
lecture and lab materials

Bootlin logo

Elixir Cross Referencer

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
/* route
 *
 * Similar to the standard Unix route, but with only the necessary
 * parts for AF_INET
 *
 * Bjorn Wesen, Axis Communications AB
 *
 * Author of the original route: 
 *              Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
 *              (derived from FvK's 'route.c     1.70    01/04/94')
 *
 * This program is free software; you can redistribute it
 * and/or  modify it under  the terms of  the GNU General
 * Public  License as  published  by  the  Free  Software
 * Foundation;  either  version 2 of the License, or  (at
 * your option) any later version.
 *
 * $Id: route.c,v 1.11 2001/08/23 22:05:33 andersen Exp $
 *
 * displayroute() code added by Vladimir N. Oleynik <dzo@simtreas.ru>
 * adjustments by Larry Doolittle  <LRDoolittle@lbl.gov>
 */

#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <net/route.h>
#include <linux/param.h>  // HZ
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#include <getopt.h>
#include <unistd.h>
#include <ctype.h>
#include "busybox.h"

#define _(x) x

#define RTACTION_ADD   1
#define RTACTION_DEL   2
#define RTACTION_HELP  3
#define RTACTION_FLUSH 4
#define RTACTION_SHOW  5

#define E_NOTFOUND      8
#define E_SOCK          7
#define E_LOOKUP        6
#define E_VERSION       5
#define E_USAGE         4
#define E_OPTERR        3
#define E_INTERN        2
#define E_NOSUPP        1

/* resolve XXX.YYY.ZZZ.QQQ -> binary */

static int
INET_resolve(char *name, struct sockaddr *sa)
{
	struct sockaddr_in *s_in = (struct sockaddr_in *)sa;
	
	s_in->sin_family = AF_INET;
	s_in->sin_port = 0;

	/* Default is special, meaning 0.0.0.0. */
	if (strcmp(name, "default")==0) {
		s_in->sin_addr.s_addr = INADDR_ANY;
		return 1;
	}
	/* Look to see if it's a dotted quad. */
	if (inet_aton(name, &s_in->sin_addr)) {
		return 0;
	}
	/* guess not.. */
	return -1;
}

#if defined (SIOCADDRTOLD) || defined (RTF_IRTT)        /* route */
#define HAVE_NEW_ADDRT 1
#endif
#ifdef RTF_IRTT                 /* route */
#define HAVE_RTF_IRTT 1
#endif
#ifdef RTF_REJECT               /* route */
#define HAVE_RTF_REJECT 1
#endif

#if HAVE_NEW_ADDRT
#define mask_in_addr(x) (((struct sockaddr_in *)&((x).rt_genmask))->sin_addr.s_addr)
#define full_mask(x) (x)
#else
#define mask_in_addr(x) ((x).rt_genmask)
#define full_mask(x) (((struct sockaddr_in *)&(x))->sin_addr.s_addr)
#endif

/* add or delete a route depending on action */

static int
INET_setroute(int action, int options, char **args)
{
	struct rtentry rt;
	char target[128], gateway[128] = "NONE", netmask[128] = "default";
	int xflag, isnet;
	int skfd;

	xflag = 0;

	if (*args == NULL)
	    show_usage();
	if (strcmp(*args, "-net")==0) {
		xflag = 1;
		args++;
	} else if (strcmp(*args, "-host")==0) {
		xflag = 2;
		args++;
	}
	safe_strncpy(target, *args++, (sizeof target));

	/* Clean out the RTREQ structure. */
	memset((char *) &rt, 0, sizeof(struct rtentry));


	if ((isnet = INET_resolve(target, &rt.rt_dst)) < 0) {
		error_msg(_("can't resolve %s"), target);
		return EXIT_FAILURE;   /* XXX change to E_something */
	}

	switch (xflag) {
		case 1:
			isnet = 1;
			break;
			
		case 2:
			isnet = 0;
			break;
			
		default:
			break;
	}
	
	/* Fill in the other fields. */
	rt.rt_flags = (RTF_UP | RTF_HOST);
	if (isnet)
		rt.rt_flags &= ~RTF_HOST;

	while (*args) {
		if (strcmp(*args, "metric")==0) {
			int metric;
			
			args++;
			if (!*args || !isdigit(**args))
				show_usage();
			metric = atoi(*args);
#if HAVE_NEW_ADDRT
			rt.rt_metric = metric + 1;
#else
			ENOSUPP("inet_setroute", "NEW_ADDRT (metric)");  /* XXX Fixme */
#endif
			args++;
			continue;
		}

		if (strcmp(*args, "netmask")==0) {
			struct sockaddr mask;
			
			args++;
			if (!*args || mask_in_addr(rt))
				show_usage();
			safe_strncpy(netmask, *args, (sizeof netmask));
			if ((isnet = INET_resolve(netmask, &mask)) < 0) {
				error_msg(_("can't resolve netmask %s"), netmask);
				return E_LOOKUP;
			}
			rt.rt_genmask = full_mask(mask);
			args++;
			continue;
		}

		if (strcmp(*args, "gw")==0 || strcmp(*args, "gateway")==0) {
			args++;
			if (!*args)
				show_usage();
			if (rt.rt_flags & RTF_GATEWAY)
				show_usage();
			safe_strncpy(gateway, *args, (sizeof gateway));
			if ((isnet = INET_resolve(gateway, &rt.rt_gateway)) < 0) {
				error_msg(_("can't resolve gw %s"), gateway);
				return E_LOOKUP;
			}
			if (isnet) {
				error_msg(
					_("%s: cannot use a NETWORK as gateway!"),
					gateway);
				return E_OPTERR;
			}
			rt.rt_flags |= RTF_GATEWAY;
			args++;
			continue;
		}

		if (strcmp(*args, "mss")==0) {
			args++;
			rt.rt_flags |= RTF_MSS;
			if (!*args)
				show_usage();
			rt.rt_mss = atoi(*args);
			args++;
			if (rt.rt_mss < 64 || rt.rt_mss > 32768) {
				error_msg(_("Invalid MSS."));
				return E_OPTERR;
			}
			continue;
		}

		if (strcmp(*args, "window")==0) {
			args++;
			if (!*args)
				show_usage();
			rt.rt_flags |= RTF_WINDOW;
			rt.rt_window = atoi(*args);
			args++;
			if (rt.rt_window < 128) {
				error_msg(_("Invalid window."));
				return E_OPTERR;
			}
			continue;
		}

		if (strcmp(*args, "irtt")==0) {
			args++;
			if (!*args)
				show_usage();
			args++;
#if HAVE_RTF_IRTT
			rt.rt_flags |= RTF_IRTT;
			rt.rt_irtt = atoi(*(args - 1));
			rt.rt_irtt *= (HZ / 100);	/* FIXME */
#if 0				/* FIXME: do we need to check anything of this? */
			if (rt.rt_irtt < 1 || rt.rt_irtt > (120 * HZ)) {
				error_msg(_("Invalid initial rtt."));
				return E_OPTERR;
			}
#endif
#else
			ENOSUPP("inet_setroute", "RTF_IRTT"); /* XXX Fixme */
#endif
			continue;
		}

		if (strcmp(*args, "reject")==0) {
			args++;
#if HAVE_RTF_REJECT
			rt.rt_flags |= RTF_REJECT;
#else
			ENOSUPP("inet_setroute", "RTF_REJECT"); /* XXX Fixme */
#endif
			continue;
		}
		if (strcmp(*args, "mod")==0) {
			args++;
			rt.rt_flags |= RTF_MODIFIED;
			continue;
		}
		if (strcmp(*args, "dyn")==0) {
			args++;
			rt.rt_flags |= RTF_DYNAMIC;
			continue;
		}
		if (strcmp(*args, "reinstate")==0) {
			args++;
			rt.rt_flags |= RTF_REINSTATE;
			continue;
		}
		if (strcmp(*args, "device")==0 || strcmp(*args, "dev")==0) {
			args++;
			if (rt.rt_dev || *args == NULL)
				show_usage();
			rt.rt_dev = *args++;
			continue;
		}
		/* nothing matches */
		if (!rt.rt_dev) {
			rt.rt_dev = *args++;
			if (*args)
				show_usage();	/* must be last to catch typos */
		} else {
			show_usage();
		}
	}

#if HAVE_RTF_REJECT
	if ((rt.rt_flags & RTF_REJECT) && !rt.rt_dev)
		rt.rt_dev = "lo";
#endif

	/* sanity checks.. */
	if (mask_in_addr(rt)) {
		unsigned long mask = mask_in_addr(rt);
		mask = ~ntohl(mask);
		if ((rt.rt_flags & RTF_HOST) && mask != 0xffffffff) {
			error_msg(
				_("netmask %.8x doesn't make sense with host route"),
				(unsigned int)mask);
			return E_OPTERR;
		}
		if (mask & (mask + 1)) {
			error_msg(_("bogus netmask %s"), netmask);
			return E_OPTERR;
		}
		mask = ((struct sockaddr_in *) &rt.rt_dst)->sin_addr.s_addr;
		if (mask & ~mask_in_addr(rt)) {
			error_msg(_("netmask doesn't match route address"));
			return E_OPTERR;
		}
	}
	/* Fill out netmask if still unset */
	if ((action == RTACTION_ADD) && rt.rt_flags & RTF_HOST)
		mask_in_addr(rt) = 0xffffffff;

	/* Create a socket to the INET kernel. */
	if ((skfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
		perror("socket");
		return E_SOCK;
	}
	/* Tell the kernel to accept this route. */
	if (action == RTACTION_DEL) {
		if (ioctl(skfd, SIOCDELRT, &rt) < 0) {
			perror("SIOCDELRT");
			close(skfd);
			return E_SOCK;
		}
	} else {
		if (ioctl(skfd, SIOCADDRT, &rt) < 0) {
			perror("SIOCADDRT");
			close(skfd);
			return E_SOCK;
		}
	}
	
	/* Close the socket. */
	(void) close(skfd);
	return EXIT_SUCCESS;
}

static void displayroutes(void)
{
	char buff[256];
	int  nl = 0 ;
	struct in_addr dest;
	struct in_addr gw;
	struct in_addr mask;
	int flgs, ref, use, metric;
	char flags[4];
	unsigned long int d,g,m;

	char sdest[16], sgw[16];


	FILE *fp = xfopen("/proc/net/route", "r");

	while( fgets(buff, sizeof(buff), fp) != NULL ) {
		if(nl) {
			int ifl = 0;
			while(buff[ifl]!=' ' && buff[ifl]!='\t' && buff[ifl]!='\0')
				ifl++;
			buff[ifl]=0;    /* interface */
			if(sscanf(buff+ifl+1, "%lx%lx%d%d%d%d%lx",
			   &d, &g, &flgs, &ref, &use, &metric, &m)!=7) {
				error_msg_and_die( "Unsuported kernel route format\n");
			}
			if(nl==1) {
                printf("Kernel IP routing table\n"
"Destination     Gateway         Genmask         Flags Metric Ref    Use Iface\n");
			} else {
			    nl++;
			    continue;
			}

			ifl = 0;        /* parse flags */
			if(flgs&1)
				flags[ifl++]='U';
			if(flgs&2)
				flags[ifl++]='G';
			if(flgs&4)
				flags[ifl++]='H';
			flags[ifl]=0;
			dest.s_addr = d;
			gw.s_addr   = g;
			mask.s_addr = m;
			strcpy(sdest,  (dest.s_addr==0 ? "default" :
					inet_ntoa(dest)));
			strcpy(sgw,    (gw.s_addr==0   ? "*"       :
					inet_ntoa(gw)));
			printf("%-16s%-16s%-16s%-6s%-6d %-2d %7d %s\n",
				sdest, sgw,
				inet_ntoa(mask),
				flags, metric, ref, use, buff);
		}
	nl++;
	}
}

int route_main(int argc, char **argv)
{
	int what = 0;

	argc--;
	argv++;

	if (*argv == NULL) {
		displayroutes();
		return EXIT_SUCCESS;
	} else {
		/* check verb */
		if (strcmp(*argv, "add")==0)
			what = RTACTION_ADD;
		else if (strcmp(*argv, "del")==0 || strcmp(*argv, "delete")==0)
			what = RTACTION_DEL;
		else if (strcmp(*argv, "flush")==0)
			what = RTACTION_FLUSH;
		else
			show_usage();
	}

	return INET_setroute(what, 0, ++argv);
}