busybox/networking/arp.c

/* vi: set sw=4 ts=4: */
/*
 * arp.c - Manipulate the system ARP cache
 *
 * 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.
 *
 * Author: Fred N. van Kempen, <waltje at uwalt.nl.mugnet.org>
 * Busybox port: Paul van Gool <pvangool at mimotech.com>
 *
 * modified for getopt32 by Arne Bernin <arne [at] alamut.de>
 */

#include "busybox.h"
#include "inet_common.h"

#include <arpa/inet.h>
#include <net/if.h>
#include <net/if_arp.h>
#include <netinet/ether.h>
#include <netpacket/packet.h>

#define DEBUG 0

#define DFLT_AF "inet"
#define DFLT_HW "ether"

#define _PATH_PROCNET_ARP "/proc/net/arp"

#define	ARP_OPT_A (0x1)
#define	ARP_OPT_p (0x2)
#define	ARP_OPT_H (0x4)
#define	ARP_OPT_t (0x8)
#define	ARP_OPT_i (0x10)
#define	ARP_OPT_a (0x20)
#define	ARP_OPT_d (0x40)
#define	ARP_OPT_n (0x80)	/* do not resolve addresses     */
#define	ARP_OPT_D (0x100)	/* HW-address is devicename     */
#define	ARP_OPT_s (0x200)
#define	ARP_OPT_v (0x400 * DEBUG)	/* debugging output flag        */


static const struct aftype *ap; /* current address family       */
static const struct hwtype *hw; /* current hardware type        */
static int sockfd;              /* active socket descriptor     */
static smallint hw_set;         /* flag if hw-type was set (-H) */
static char *device = "";       /* current device               */

static const char *const options[] = {
	"pub",
	"priv",
	"temp",
	"trail",
	"dontpub",
	"auto",
	"dev",
	"netmask",
	NULL
};

/* Delete an entry from the ARP cache. */
/* Called only from main, once */
static int arp_del(char **args)
{
	char host[128];
	struct arpreq req;
	struct sockaddr sa;
	int flags = 0;
	int err;

	memset(&req, 0, sizeof(req));

	/* Resolve the host name. */
	safe_strncpy(host, *args, 128);
	if (ap->input(0, host, &sa) < 0) {
		bb_herror_msg_and_die("%s", host);
	}

	/* If a host has more than one address, use the correct one! */
	memcpy(&req.arp_pa, &sa, sizeof(struct sockaddr));

	if (hw_set)
		req.arp_ha.sa_family = hw->type;

	req.arp_flags = ATF_PERM;
	args++;
	while (*args != NULL) {
		switch (index_in_str_array(options, *args)) {
		case 0: /* "pub" */
			flags |= 1;
			args++;
			break;
		case 1: /* "priv" */
			flags |= 2;
			args++;
			break;
		case 2: /* "temp" */
			req.arp_flags &= ~ATF_PERM;
			args++;
			break;
		case 3: /* "trail" */
			req.arp_flags |= ATF_USETRAILERS;
			args++;
			break;
		case 4: /* "dontpub" */
#ifdef HAVE_ATF_DONTPUB
			req.arp_flags |= ATF_DONTPUB;
#else
			bb_error_msg("feature ATF_DONTPUB is not supported");
#endif
			args++;
			break;
		case 5: /* "auto" */
#ifdef HAVE_ATF_MAGIC
			req.arp_flags |= ATF_MAGIC;
#else
			bb_error_msg("feature ATF_MAGIC is not supported");
#endif
			args++;
			break;
		case 6: /* "dev" */
			if (*++args == NULL)
				bb_show_usage();
			device = *args;
			args++;
			break;
		case 7: /* "netmask" */
			if (*++args == NULL)
				bb_show_usage();
			if (strcmp(*args, "255.255.255.255") != 0) {
				safe_strncpy(host, *args, 128);
				if (ap->input(0, host, &sa) < 0) {
					bb_herror_msg_and_die("%s", host);
				}
				memcpy(&req.arp_netmask, &sa, sizeof(struct sockaddr));
				req.arp_flags |= ATF_NETMASK;
			}
			args++;
			break;
		default:
			bb_show_usage();
			break;
		}
	}
	if (flags == 0)
		flags = 3;

	strncpy(req.arp_dev, device, sizeof(req.arp_dev));

	err = -1;

	/* Call the kernel. */
	if (flags & 2) {
		if (option_mask32 & ARP_OPT_v)
			bb_error_msg("SIOCDARP(nopub)");
		err = ioctl(sockfd, SIOCDARP, &req);
		if (err < 0) {
			if (errno == ENXIO) {
				if (flags & 1)
					goto nopub;
				printf("No ARP entry for %s\n", host);
				return -1;
			}
			bb_perror_msg_and_die("SIOCDARP(priv)");
		}
	}
	if ((flags & 1) && err) {
 nopub:
		req.arp_flags |= ATF_PUBL;
		if (option_mask32 & ARP_OPT_v)
			bb_error_msg("SIOCDARP(pub)");
		if (ioctl(sockfd, SIOCDARP, &req) < 0) {
			if (errno == ENXIO) {
				printf("No ARP entry for %s\n", host);
				return -1;
			}
			bb_perror_msg_and_die("SIOCDARP(pub)");
		}
	}
	return 0;
}

/* Get the hardware address to a specified interface name */
static void arp_getdevhw(char *ifname, struct sockaddr *sa,
						 const struct hwtype *hwt)
{
	struct ifreq ifr;
	const struct hwtype *xhw;

	strcpy(ifr.ifr_name, ifname);
	if (ioctl(sockfd, SIOCGIFHWADDR, &ifr) < 0) {
		bb_perror_msg_and_die("cant get HW-Address for '%s'", ifname);
	}
	if (hwt && (ifr.ifr_hwaddr.sa_family != hw->type)) {
		bb_error_msg_and_die("protocol type mismatch");
	}
	memcpy(sa, &(ifr.ifr_hwaddr), sizeof(struct sockaddr));

	if (option_mask32 & ARP_OPT_v) {
		xhw = get_hwntype(ifr.ifr_hwaddr.sa_family);
		if (!xhw || !xhw->print) {
			xhw = get_hwntype(-1);
		}
		bb_error_msg("device '%s' has HW address %s '%s'",
					 ifname, xhw->name,
					 xhw->print((char *) &ifr.ifr_hwaddr.sa_data));
	}
}

/* Set an entry in the ARP cache. */
/* Called only from main, once */
static int arp_set(char **args)
{
	char host[128];
	struct arpreq req;
	struct sockaddr sa;
	int flags;

	memset(&req, 0, sizeof(req));

	safe_strncpy(host, *args++, 128);
	if (ap->input(0, host, &sa) < 0) {
		bb_herror_msg_and_die("%s", host);
	}
	/* If a host has more than one address, use the correct one! */
	memcpy(&req.arp_pa, &sa, sizeof(struct sockaddr));

	/* Fetch the hardware address. */
	if (*args == NULL) {
		bb_error_msg_and_die("need hardware address");
	}
	if (option_mask32 & ARP_OPT_D) {
		arp_getdevhw(*args++, &req.arp_ha, hw_set ? hw : NULL);
	} else {
		if (hw->input(*args++, &req.arp_ha) < 0) {
			bb_error_msg_and_die("invalid hardware address");
		}
	}

	/* Check out any modifiers. */
	flags = ATF_PERM | ATF_COM;
	while (*args != NULL) {
		switch (index_in_str_array(options, *args)) {
		case 0: /* "pub" */
			flags |= ATF_PUBL;
			args++;
			break;
		case 1: /* "priv" */
			flags &= ~ATF_PUBL;
			args++;
			break;
		case 2: /* "temp" */
			flags &= ~ATF_PERM;
			args++;
			break;
		case 3: /* "trail" */
			flags |= ATF_USETRAILERS;
			args++;
			break;
		case 4: /* "dontpub" */
#ifdef HAVE_ATF_DONTPUB
			flags |= ATF_DONTPUB;
#else
			bb_error_msg("feature ATF_DONTPUB is not supported");
#endif
			args++;
			break;
		case 5: /* "auto" */
#ifdef HAVE_ATF_MAGIC
			flags |= ATF_MAGIC;
#else
			bb_error_msg("feature ATF_MAGIC is not supported");
#endif
			args++;
			break;
		case 6: /* "dev" */
			if (*++args == NULL)
				bb_show_usage();
			device = *args;
			args++;
			break;
		case 7: /* "netmask" */
			if (*++args == NULL)
				bb_show_usage();
			if (strcmp(*args, "255.255.255.255") != 0) {
				safe_strncpy(host, *args++, 128);
				if (ap->input(0, host, &sa) < 0) {
					bb_herror_msg_and_die("%s", host);
				}
				memcpy(&req.arp_netmask, &sa, sizeof(struct sockaddr));
				flags |= ATF_NETMASK;
			}
			args++;
			break;
		default:
			bb_show_usage();
			break;
		}
	}

	/* Fill in the remainder of the request. */
	req.arp_flags = flags;

	strncpy(req.arp_dev, device, sizeof(req.arp_dev));

	/* Call the kernel. */
	if (option_mask32 & ARP_OPT_v)
		bb_error_msg("SIOCSARP()");
	if (ioctl(sockfd, SIOCSARP, &req) < 0) {
		bb_perror_msg_and_die("SIOCSARP");
	}
	return 0;
}


/* Print the contents of an ARP request block. */
static void
arp_disp(char *name, char *ip, int type, int arp_flags,
		 char *hwa, char *mask, char *dev)
{
	const struct hwtype *xhw;

	xhw = get_hwntype(type);
	if (xhw == NULL)
		xhw = get_hwtype(DFLT_HW);

	printf("%s (%s) at ", name, ip);

	if (!(arp_flags & ATF_COM)) {
		if (arp_flags & ATF_PUBL)
			printf("* ");
		else
			printf("<incomplete> ");
	} else {
		printf("%s [%s] ", hwa, xhw->name);
	}

	if (arp_flags & ATF_NETMASK)
		printf("netmask %s ", mask);

	if (arp_flags & ATF_PERM)
		printf("PERM ");
	if (arp_flags & ATF_PUBL)
		printf("PUP ");
#ifdef HAVE_ATF_MAGIC
	if (arp_flags & ATF_MAGIC)
		printf("AUTO ");
#endif
#ifdef HAVE_ATF_DONTPUB
	if (arp_flags & ATF_DONTPUB)
		printf("DONTPUB ");
#endif
	if (arp_flags & ATF_USETRAILERS)
		printf("TRAIL ");

	printf("on %s\n", dev);
}

/* Display the contents of the ARP cache in the kernel. */
/* Called only from main, once */
static int arp_show(char *name)
{
	char host[100];
	struct sockaddr sa;
	char ip[100];
	char hwa[100];
	char mask[100];
	char line[200];
	char dev[100];
	int type, flags;
	FILE *fp;
	char *hostname;
	int num;
	unsigned entries = 0, shown = 0;

	host[0] = '\0';

	if (name != NULL) {
		/* Resolve the host name. */
		safe_strncpy(host, name, (sizeof host));
		if (ap->input(0, host, &sa) < 0) {
			bb_herror_msg_and_die("%s", host);
		}
		safe_strncpy(host, ap->sprint(&sa, 1), sizeof(host));
	}
	/* Open the PROCps kernel table. */
	fp = xfopen(_PATH_PROCNET_ARP, "r");
	/* Bypass header -- read until newline */
	if (fgets(line, sizeof(line), fp) != (char *) NULL) {
		mask[0] = '-'; mask[1] = '\0';
		dev[0] = '-'; dev[1] = '\0';
		/* Read the ARP cache entries. */
		for (; fgets(line, sizeof(line), fp);) {
			num = sscanf(line, "%s 0x%x 0x%x %100s %100s %100s\n",
						 ip, &type, &flags, hwa, mask, dev);
			if (num < 4)
				break;

			entries++;
			/* if the user specified hw-type differs, skip it */
			if (hw_set && (type != hw->type))
				continue;

			/* if the user specified address differs, skip it */
			if (host[0] && strcmp(ip, host) != 0)
				continue;

			/* if the user specified device differs, skip it */
			if (device[0] && strcmp(dev, device) != 0)
				continue;

			shown++;
			/* This IS ugly but it works -be */
			if (option_mask32 & ARP_OPT_n)
				hostname = "?";
			else {
				if (ap->input(0, ip, &sa) < 0)
					hostname = ip;
				else
					hostname = ap->sprint(&sa, (option_mask32 & ARP_OPT_n) | 0x8000);
				if (strcmp(hostname, ip) == 0)
					hostname = "?";
			}

			arp_disp(hostname, ip, type, flags, hwa, mask, dev);
		}
	}
	if (option_mask32 & ARP_OPT_v)
		printf("Entries: %d\tSkipped: %d\tFound: %d\n",
			   entries, entries - shown, shown);

	if (!shown) {
		if (hw_set || host[0] || device[0])
			printf("No match found in %d entries\n", entries);
	}

	fclose(fp);

	return 0;
}

int arp_main(int argc, char **argv)
{
	char *hw_type;
	char *protocol;

	/* Initialize variables... */
	ap = get_aftype(DFLT_AF);
	if (!ap)
		bb_error_msg_and_die("%s: %s not supported", DFLT_AF, "address family");

	getopt32(argc, argv, "A:p:H:t:i:adnDsv", &protocol, &protocol,
				 &hw_type, &hw_type, &device);
	argv += optind;
	if (option_mask32 & ARP_OPT_A || option_mask32 & ARP_OPT_p) {
		ap = get_aftype(protocol);
		if (ap == NULL)
			bb_error_msg_and_die("%s: unknown %s", protocol, "address family");
	}
	if (option_mask32 & ARP_OPT_A || option_mask32 & ARP_OPT_p) {
		hw = get_hwtype(hw_type);
		if (hw == NULL)
			bb_error_msg_and_die("%s: unknown %s", hw_type, "hardware type");
		hw_set = 1;
	}
	//if (option_mask32 & ARP_OPT_i)... -i

	if (ap->af != AF_INET) {
		bb_error_msg_and_die("%s: kernel only supports 'inet'", ap->name);
	}

	/* If no hw type specified get default */
	if (!hw) {
		hw = get_hwtype(DFLT_HW);
		if (!hw)
			bb_error_msg_and_die("%s: %s not supported", DFLT_HW, "hardware type");
	}

	if (hw->alen <= 0) {
		bb_error_msg_and_die("%s: %s without ARP support",
							 hw->name, "hardware type");
	}
	sockfd = xsocket(AF_INET, SOCK_DGRAM, 0);

	/* Now see what we have to do here... */
	if (option_mask32 & (ARP_OPT_d|ARP_OPT_s)) {
		if (argv[0] == NULL)
			bb_error_msg_and_die("need host name");
		if (option_mask32 & ARP_OPT_s)
			return arp_set(argv);
		return arp_del(argv);
	}
	//if (option_mask32 & ARP_OPT_a) - default
	return arp_show(argv[0]);
}
1	/* vi: set sw=4 ts=4: */
2	/*
3	* arp.c - Manipulate the system ARP cache
4	*
5	* This program is free software; you can redistribute it and/or
6	* modify it under the terms of the GNU General Public License
7	* as published by the Free Software Foundation; either version
8	* 2 of the License, or (at your option) any later version.
9	*
10	* Author: Fred N. van Kempen, <waltje at uwalt.nl.mugnet.org>
11	* Busybox port: Paul van Gool <pvangool at mimotech.com>
12	*
13	* modified for getopt32 by Arne Bernin <arne [at] alamut.de>
14	*/
15
16	#include "busybox.h"
17	#include "inet_common.h"
18
19	#include <arpa/inet.h>
20	#include <net/if.h>
21	#include <net/if_arp.h>
22	#include <netinet/ether.h>
23	#include <netpacket/packet.h>
24
25	#define DEBUG 0
26
27	#define DFLT_AF "inet"
28	#define DFLT_HW "ether"
29
30	#define _PATH_PROCNET_ARP "/proc/net/arp"
31
32	#define ARP_OPT_A (0x1)
33	#define ARP_OPT_p (0x2)
34	#define ARP_OPT_H (0x4)
35	#define ARP_OPT_t (0x8)
36	#define ARP_OPT_i (0x10)
37	#define ARP_OPT_a (0x20)
38	#define ARP_OPT_d (0x40)
39	#define ARP_OPT_n (0x80) /* do not resolve addresses */
40	#define ARP_OPT_D (0x100) /* HW-address is devicename */
41	#define ARP_OPT_s (0x200)
42	#define ARP_OPT_v (0x400 * DEBUG) /* debugging output flag */
43
44
45	static const struct aftype ap; / current address family */
46	static const struct hwtype hw; / current hardware type */
47	static int sockfd; /* active socket descriptor */
48	static smallint hw_set; /* flag if hw-type was set (-H) */
49	static char device = ""; / current device */
50
51	static const char *const options[] = {
52	"pub",
53	"priv",
54	"temp",
55	"trail",
56	"dontpub",
57	"auto",
58	"dev",
59	"netmask",
60	NULL
61	};
62
63	/* Delete an entry from the ARP cache. */
64	/* Called only from main, once */
65	static int arp_del(char **args)
66	{
67	char host[128];
68	struct arpreq req;
69	struct sockaddr sa;
70	int flags = 0;
71	int err;
72
73	memset(&req, 0, sizeof(req));
74
75	/* Resolve the host name. */
76	safe_strncpy(host, *args, 128);
77	if (ap->input(0, host, &sa) < 0) {
78	bb_herror_msg_and_die("%s", host);
79	}
80
81	/* If a host has more than one address, use the correct one! */
82	memcpy(&req.arp_pa, &sa, sizeof(struct sockaddr));
83
84	if (hw_set)
85	req.arp_ha.sa_family = hw->type;
86
87	req.arp_flags = ATF_PERM;
88	args++;
89	while (*args != NULL) {
90	switch (index_in_str_array(options, *args)) {
91	case 0: /* "pub" */
92	flags \|= 1;
93	args++;
94	break;
95	case 1: /* "priv" */
96	flags \|= 2;
97	args++;
98	break;
99	case 2: /* "temp" */
100	req.arp_flags &= ~ATF_PERM;
101	args++;
102	break;
103	case 3: /* "trail" */
104	req.arp_flags \|= ATF_USETRAILERS;
105	args++;
106	break;
107	case 4: /* "dontpub" */
108	#ifdef HAVE_ATF_DONTPUB
109	req.arp_flags \|= ATF_DONTPUB;
110	#else
111	bb_error_msg("feature ATF_DONTPUB is not supported");
112	#endif
113	args++;
114	break;
115	case 5: /* "auto" */
116	#ifdef HAVE_ATF_MAGIC
117	req.arp_flags \|= ATF_MAGIC;
118	#else
119	bb_error_msg("feature ATF_MAGIC is not supported");
120	#endif
121	args++;
122	break;
123	case 6: /* "dev" */
124	if (*++args == NULL)
125	bb_show_usage();
126	device = *args;
127	args++;
128	break;
129	case 7: /* "netmask" */
130	if (*++args == NULL)
131	bb_show_usage();
132	if (strcmp(*args, "255.255.255.255") != 0) {
133	safe_strncpy(host, *args, 128);
134	if (ap->input(0, host, &sa) < 0) {
135	bb_herror_msg_and_die("%s", host);
136	}
137	memcpy(&req.arp_netmask, &sa, sizeof(struct sockaddr));
138	req.arp_flags \|= ATF_NETMASK;
139	}
140	args++;
141	break;
142	default:
143	bb_show_usage();
144	break;
145	}
146	}
147	if (flags == 0)
148	flags = 3;
149
150	strncpy(req.arp_dev, device, sizeof(req.arp_dev));
151
152	err = -1;
153
154	/* Call the kernel. */
155	if (flags & 2) {
156	if (option_mask32 & ARP_OPT_v)
157	bb_error_msg("SIOCDARP(nopub)");
158	err = ioctl(sockfd, SIOCDARP, &req);
159	if (err < 0) {
160	if (errno == ENXIO) {
161	if (flags & 1)
162	goto nopub;
163	printf("No ARP entry for %s\n", host);
164	return -1;
165	}
166	bb_perror_msg_and_die("SIOCDARP(priv)");
167	}
168	}
169	if ((flags & 1) && err) {
170	nopub:
171	req.arp_flags \|= ATF_PUBL;
172	if (option_mask32 & ARP_OPT_v)
173	bb_error_msg("SIOCDARP(pub)");
174	if (ioctl(sockfd, SIOCDARP, &req) < 0) {
175	if (errno == ENXIO) {
176	printf("No ARP entry for %s\n", host);
177	return -1;
178	}
179	bb_perror_msg_and_die("SIOCDARP(pub)");
180	}
181	}
182	return 0;
183	}
184
185	/* Get the hardware address to a specified interface name */
186	static void arp_getdevhw(char ifname, struct sockaddr sa,
187	const struct hwtype *hwt)
188	{
189	struct ifreq ifr;
190	const struct hwtype *xhw;
191
192	strcpy(ifr.ifr_name, ifname);
193	if (ioctl(sockfd, SIOCGIFHWADDR, &ifr) < 0) {
194	bb_perror_msg_and_die("cant get HW-Address for '%s'", ifname);
195	}
196	if (hwt && (ifr.ifr_hwaddr.sa_family != hw->type)) {
197	bb_error_msg_and_die("protocol type mismatch");
198	}
199	memcpy(sa, &(ifr.ifr_hwaddr), sizeof(struct sockaddr));
200
201	if (option_mask32 & ARP_OPT_v) {
202	xhw = get_hwntype(ifr.ifr_hwaddr.sa_family);
203	if (!xhw \|\| !xhw->print) {
204	xhw = get_hwntype(-1);
205	}
206	bb_error_msg("device '%s' has HW address %s '%s'",
207	ifname, xhw->name,
208	xhw->print((char *) &ifr.ifr_hwaddr.sa_data));
209	}
210	}
211
212	/* Set an entry in the ARP cache. */
213	/* Called only from main, once */
214	static int arp_set(char **args)
215	{
216	char host[128];
217	struct arpreq req;
218	struct sockaddr sa;
219	int flags;
220
221	memset(&req, 0, sizeof(req));
222
223	safe_strncpy(host, *args++, 128);
224	if (ap->input(0, host, &sa) < 0) {
225	bb_herror_msg_and_die("%s", host);
226	}
227	/* If a host has more than one address, use the correct one! */
228	memcpy(&req.arp_pa, &sa, sizeof(struct sockaddr));
229
230	/* Fetch the hardware address. */
231	if (*args == NULL) {
232	bb_error_msg_and_die("need hardware address");
233	}
234	if (option_mask32 & ARP_OPT_D) {
235	arp_getdevhw(*args++, &req.arp_ha, hw_set ? hw : NULL);
236	} else {
237	if (hw->input(*args++, &req.arp_ha) < 0) {
238	bb_error_msg_and_die("invalid hardware address");
239	}
240	}
241
242	/* Check out any modifiers. */
243	flags = ATF_PERM \| ATF_COM;
244	while (*args != NULL) {
245	switch (index_in_str_array(options, *args)) {
246	case 0: /* "pub" */
247	flags \|= ATF_PUBL;
248	args++;
249	break;
250	case 1: /* "priv" */
251	flags &= ~ATF_PUBL;
252	args++;
253	break;
254	case 2: /* "temp" */
255	flags &= ~ATF_PERM;
256	args++;
257	break;
258	case 3: /* "trail" */
259	flags \|= ATF_USETRAILERS;
260	args++;
261	break;
262	case 4: /* "dontpub" */
263	#ifdef HAVE_ATF_DONTPUB
264	flags \|= ATF_DONTPUB;
265	#else
266	bb_error_msg("feature ATF_DONTPUB is not supported");
267	#endif
268	args++;
269	break;
270	case 5: /* "auto" */
271	#ifdef HAVE_ATF_MAGIC
272	flags \|= ATF_MAGIC;
273	#else
274	bb_error_msg("feature ATF_MAGIC is not supported");
275	#endif
276	args++;
277	break;
278	case 6: /* "dev" */
279	if (*++args == NULL)
280	bb_show_usage();
281	device = *args;
282	args++;
283	break;
284	case 7: /* "netmask" */
285	if (*++args == NULL)
286	bb_show_usage();
287	if (strcmp(*args, "255.255.255.255") != 0) {
288	safe_strncpy(host, *args++, 128);
289	if (ap->input(0, host, &sa) < 0) {
290	bb_herror_msg_and_die("%s", host);
291	}
292	memcpy(&req.arp_netmask, &sa, sizeof(struct sockaddr));
293	flags \|= ATF_NETMASK;
294	}
295	args++;
296	break;
297	default:
298	bb_show_usage();
299	break;
300	}
301	}
302
303	/* Fill in the remainder of the request. */
304	req.arp_flags = flags;
305
306	strncpy(req.arp_dev, device, sizeof(req.arp_dev));
307
308	/* Call the kernel. */
309	if (option_mask32 & ARP_OPT_v)
310	bb_error_msg("SIOCSARP()");
311	if (ioctl(sockfd, SIOCSARP, &req) < 0) {
312	bb_perror_msg_and_die("SIOCSARP");
313	}
314	return 0;
315	}
316
317
318	/* Print the contents of an ARP request block. */
319	static void
320	arp_disp(char name, char ip, int type, int arp_flags,
321	char hwa, char mask, char *dev)
322	{
323	const struct hwtype *xhw;
324
325	xhw = get_hwntype(type);
326	if (xhw == NULL)
327	xhw = get_hwtype(DFLT_HW);
328
329	printf("%s (%s) at ", name, ip);
330
331	if (!(arp_flags & ATF_COM)) {
332	if (arp_flags & ATF_PUBL)
333	printf("* ");
334	else
335	printf("<incomplete> ");
336	} else {
337	printf("%s [%s] ", hwa, xhw->name);
338	}
339
340	if (arp_flags & ATF_NETMASK)
341	printf("netmask %s ", mask);
342
343	if (arp_flags & ATF_PERM)
344	printf("PERM ");
345	if (arp_flags & ATF_PUBL)
346	printf("PUP ");
347	#ifdef HAVE_ATF_MAGIC
348	if (arp_flags & ATF_MAGIC)
349	printf("AUTO ");
350	#endif
351	#ifdef HAVE_ATF_DONTPUB
352	if (arp_flags & ATF_DONTPUB)
353	printf("DONTPUB ");
354	#endif
355	if (arp_flags & ATF_USETRAILERS)
356	printf("TRAIL ");
357
358	printf("on %s\n", dev);
359	}
360
361	/* Display the contents of the ARP cache in the kernel. */
362	/* Called only from main, once */
363	static int arp_show(char *name)
364	{
365	char host[100];
366	struct sockaddr sa;
367	char ip[100];
368	char hwa[100];
369	char mask[100];
370	char line[200];
371	char dev[100];
372	int type, flags;
373	FILE *fp;
374	char *hostname;
375	int num;
376	unsigned entries = 0, shown = 0;
377
378	host[0] = '\0';
379
380	if (name != NULL) {
381	/* Resolve the host name. */
382	safe_strncpy(host, name, (sizeof host));
383	if (ap->input(0, host, &sa) < 0) {
384	bb_herror_msg_and_die("%s", host);
385	}
386	safe_strncpy(host, ap->sprint(&sa, 1), sizeof(host));
387	}
388	/* Open the PROCps kernel table. */
389	fp = xfopen(_PATH_PROCNET_ARP, "r");
390	/* Bypass header -- read until newline */
391	if (fgets(line, sizeof(line), fp) != (char *) NULL) {
392	mask[0] = '-'; mask[1] = '\0';
393	dev[0] = '-'; dev[1] = '\0';
394	/* Read the ARP cache entries. */
395	for (; fgets(line, sizeof(line), fp);) {
396	num = sscanf(line, "%s 0x%x 0x%x %100s %100s %100s\n",
397	ip, &type, &flags, hwa, mask, dev);
398	if (num < 4)
399	break;
400
401	entries++;
402	/* if the user specified hw-type differs, skip it */
403	if (hw_set && (type != hw->type))
404	continue;
405
406	/* if the user specified address differs, skip it */
407	if (host[0] && strcmp(ip, host) != 0)
408	continue;
409
410	/* if the user specified device differs, skip it */
411	if (device[0] && strcmp(dev, device) != 0)
412	continue;
413
414	shown++;
415	/* This IS ugly but it works -be */
416	if (option_mask32 & ARP_OPT_n)
417	hostname = "?";
418	else {
419	if (ap->input(0, ip, &sa) < 0)
420	hostname = ip;
421	else
422	hostname = ap->sprint(&sa, (option_mask32 & ARP_OPT_n) \| 0x8000);
423	if (strcmp(hostname, ip) == 0)
424	hostname = "?";
425	}
426
427	arp_disp(hostname, ip, type, flags, hwa, mask, dev);
428	}
429	}
430	if (option_mask32 & ARP_OPT_v)
431	printf("Entries: %d\tSkipped: %d\tFound: %d\n",
432	entries, entries - shown, shown);
433
434	if (!shown) {
435	if (hw_set \|\| host[0] \|\| device[0])
436	printf("No match found in %d entries\n", entries);
437	}
438
439	fclose(fp);
440
441	return 0;
442	}
443
444	int arp_main(int argc, char **argv)
445	{
446	char *hw_type;
447	char *protocol;
448
449	/* Initialize variables... */
450	ap = get_aftype(DFLT_AF);
451	if (!ap)
452	bb_error_msg_and_die("%s: %s not supported", DFLT_AF, "address family");
453
454	getopt32(argc, argv, "A:p:H:t:i:adnDsv", &protocol, &protocol,
455	&hw_type, &hw_type, &device);
456	argv += optind;
457	if (option_mask32 & ARP_OPT_A \|\| option_mask32 & ARP_OPT_p) {
458	ap = get_aftype(protocol);
459	if (ap == NULL)
460	bb_error_msg_and_die("%s: unknown %s", protocol, "address family");
461	}
462	if (option_mask32 & ARP_OPT_A \|\| option_mask32 & ARP_OPT_p) {
463	hw = get_hwtype(hw_type);
464	if (hw == NULL)
465	bb_error_msg_and_die("%s: unknown %s", hw_type, "hardware type");
466	hw_set = 1;
467	}
468	//if (option_mask32 & ARP_OPT_i)... -i
469
470	if (ap->af != AF_INET) {
471	bb_error_msg_and_die("%s: kernel only supports 'inet'", ap->name);
472	}
473
474	/* If no hw type specified get default */
475	if (!hw) {
476	hw = get_hwtype(DFLT_HW);
477	if (!hw)
478	bb_error_msg_and_die("%s: %s not supported", DFLT_HW, "hardware type");
479	}
480
481	if (hw->alen <= 0) {
482	bb_error_msg_and_die("%s: %s without ARP support",
483	hw->name, "hardware type");
484	}
485	sockfd = xsocket(AF_INET, SOCK_DGRAM, 0);
486
487	/* Now see what we have to do here... */
488	if (option_mask32 & (ARP_OPT_d\|ARP_OPT_s)) {
489	if (argv[0] == NULL)
490	bb_error_msg_and_die("need host name");
491	if (option_mask32 & ARP_OPT_s)
492	return arp_set(argv);
493	return arp_del(argv);
494	}
495	//if (option_mask32 & ARP_OPT_a) - default
496	return arp_show(argv[0]);
497	}