1
2/*
3 * write.c
4 *
5 * Copyright (c) 2002 Archie L. Cobbs
6 * All rights reserved.
7 *
8 * Subject to the following obligations and disclaimer of warranty, use and
9 * redistribution of this software, in source or object code forms, with or
10 * without modifications are expressly permitted by Archie L. Cobbs;
11 * provided, however, that:
12 * 1. Any and all reproductions of the source or object code must include the
13 *    copyright notice above and the following disclaimer of warranties
14 *
15 * THIS SOFTWARE IS BEING PROVIDED BY ARCHIE L. COBBS AS IS", AND TO
16 * THE MAXIMUM EXTENT PERMITTED BY LAW, ARCHIE L. COBBS MAKES NO
17 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
18 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
20 * ARCHIE L. COBBS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
21 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
22 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
23 * IN NO EVENT SHALL ARCHIE L. COBBS BE LIABLE FOR ANY DAMAGES
24 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
25 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
26 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
27 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30 * THIS SOFTWARE, EVEN IF ARCHIE L. COBBS IS ADVISED OF THE POSSIBILITY
31 * OF SUCH DAMAGE.
32 */
33
34#include <sys/types.h>
35#include <sys/socket.h>
36
37#include <err.h>
38#include <stdio.h>
39#include <string.h>
40#include <unistd.h>
41
42#include <netgraph/ng_socket.h>
43
44#include "ngctl.h"
45
46#define BUF_SIZE	8192
47
48static int WriteCmd(int ac, char **av);
49
50const struct ngcmd write_cmd = {
51	WriteCmd,
52	"write hook < -f file | byte ... >",
53	"Send a data packet down the hook named by \"hook\".",
54	"The data may be contained in a file, or may be described directly"
55	" on the command line by supplying a sequence of bytes.",
56	{ "w" }
57};
58
59static int
60WriteCmd(int ac, char **av)
61{
62	u_int32_t sagbuf[64];
63	struct sockaddr_ng *sag = (struct sockaddr_ng *)sagbuf;
64	u_char buf[BUF_SIZE];
65	const char *hook;
66	FILE *fp;
67	u_int len;
68	int byte;
69	int i;
70
71	/* Get arguments */
72	if (ac < 3)
73		return (CMDRTN_USAGE);
74	hook = av[1];
75
76	/* Get data */
77	if (strcmp(av[2], "-f") == 0) {
78		if (ac != 4)
79			return (CMDRTN_USAGE);
80		if ((fp = fopen(av[3], "r")) == NULL) {
81			warn("can't read file \"%s\"", av[3]);
82			return (CMDRTN_ERROR);
83		}
84		if ((len = fread(buf, 1, sizeof(buf), fp)) == 0) {
85			if (ferror(fp))
86				warn("can't read file \"%s\"", av[3]);
87			else
88				warnx("file \"%s\" is empty", av[3]);
89			fclose(fp);
90			return (CMDRTN_ERROR);
91		}
92		fclose(fp);
93	} else {
94		for (i = 2, len = 0; i < ac && len < sizeof(buf); i++, len++) {
95			if (sscanf(av[i], "%i", &byte) != 1
96			    || (byte < -128 || byte > 255)) {
97				warnx("invalid byte \"%s\"", av[i]);
98				return (CMDRTN_ERROR);
99			}
100			buf[len] = (u_char)byte;
101		}
102		if (len == 0)
103			return (CMDRTN_USAGE);
104	}
105
106	/* Send data */
107	sag->sg_len = 3 + strlen(hook);
108	sag->sg_family = AF_NETGRAPH;
109	strlcpy(sag->sg_data, hook, sizeof(sagbuf) - 2);
110	if (sendto(dsock, buf, len,
111	    0, (struct sockaddr *)sag, sag->sg_len) == -1) {
112		warn("writing to hook \"%s\"", hook);
113		return (CMDRTN_ERROR);
114	}
115
116	/* Done */
117	return (CMDRTN_OK);
118}
119
120