xref: /freebsd/usr.sbin/ngctl/write.c (revision 63a938566d524836885917d95bd491aa4400b181)
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  * $FreeBSD$
34  */
35 
36 #include <sys/types.h>
37 #include <sys/socket.h>
38 
39 #include <err.h>
40 #include <stdio.h>
41 #include <string.h>
42 #include <unistd.h>
43 
44 #include <netgraph/ng_socket.h>
45 
46 #include "ngctl.h"
47 
48 #define BUF_SIZE	8192
49 
50 static int WriteCmd(int ac, char **av);
51 
52 const struct ngcmd write_cmd = {
53 	WriteCmd,
54 	"write hook < -f file | byte ... >",
55 	"Send a data packet down the hook named by \"hook\".",
56 	"The data may be contained in a file, or may be described directly"
57 	" on the command line by supplying a sequence of bytes.",
58 	{ "w" }
59 };
60 
61 static int
62 WriteCmd(int ac, char **av)
63 {
64 	u_int32_t sagbuf[64];
65 	struct sockaddr_ng *sag = (struct sockaddr_ng *)sagbuf;
66 	u_char buf[BUF_SIZE];
67 	const char *hook;
68 	FILE *fp;
69 	u_int len;
70 	int byte;
71 	int i;
72 
73 	/* Get arguments */
74 	if (ac < 3)
75 		return (CMDRTN_USAGE);
76 	hook = av[1];
77 
78 	/* Get data */
79 	if (strcmp(av[2], "-f") == 0) {
80 		if (ac != 4)
81 			return (CMDRTN_USAGE);
82 		if ((fp = fopen(av[3], "r")) == NULL) {
83 			warn("can't read file \"%s\"", av[3]);
84 			return (CMDRTN_ERROR);
85 		}
86 		if ((len = fread(buf, 1, sizeof(buf), fp)) == 0) {
87 			if (ferror(fp))
88 				warn("can't read file \"%s\"", av[3]);
89 			else
90 				warnx("file \"%s\" is empty", av[3]);
91 			fclose(fp);
92 			return (CMDRTN_ERROR);
93 		}
94 		fclose(fp);
95 	} else {
96 		for (i = 2, len = 0; i < ac && len < sizeof(buf); i++, len++) {
97 			if (sscanf(av[i], "%i", &byte) != 1
98 			    || (byte < -128 || byte > 255)) {
99 				warnx("invalid byte \"%s\"", av[i]);
100 				return (CMDRTN_ERROR);
101 			}
102 			buf[len] = (u_char)byte;
103 		}
104 		if (len == 0)
105 			return (CMDRTN_USAGE);
106 	}
107 
108 	/* Send data */
109 	sag->sg_len = 3 + strlen(hook);
110 	sag->sg_family = AF_NETGRAPH;
111 	strlcpy(sag->sg_data, hook, sizeof(sagbuf) - 2);
112 	if (sendto(dsock, buf, len,
113 	    0, (struct sockaddr *)sag, sag->sg_len) == -1) {
114 		warn("writing to hook \"%s\"", hook);
115 		return (CMDRTN_ERROR);
116 	}
117 
118 	/* Done */
119 	return (CMDRTN_OK);
120 }
121 
122