xref: /freebsd/usr.sbin/ngctl/write.c (revision 2e3f49888ec8851bafb22011533217487764fdb0)
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 
48 static int WriteCmd(int ac, char **av);
49 
50 const 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 
59 static int
60 WriteCmd(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