1 /*
2 * write.c
3 *
4 * Copyright (c) 2002 Archie L. Cobbs
5 * All rights reserved.
6 *
7 * Subject to the following obligations and disclaimer of warranty, use and
8 * redistribution of this software, in source or object code forms, with or
9 * without modifications are expressly permitted by Archie L. Cobbs;
10 * provided, however, that:
11 * 1. Any and all reproductions of the source or object code must include the
12 * copyright notice above and the following disclaimer of warranties
13 *
14 * THIS SOFTWARE IS BEING PROVIDED BY ARCHIE L. COBBS AS IS", AND TO
15 * THE MAXIMUM EXTENT PERMITTED BY LAW, ARCHIE L. COBBS MAKES NO
16 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
17 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
18 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
19 * ARCHIE L. COBBS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
20 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
21 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
22 * IN NO EVENT SHALL ARCHIE L. COBBS BE LIABLE FOR ANY DAMAGES
23 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
24 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
25 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
26 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
29 * THIS SOFTWARE, EVEN IF ARCHIE L. COBBS IS ADVISED OF THE POSSIBILITY
30 * OF SUCH DAMAGE.
31 */
32
33 #include <sys/types.h>
34 #include <sys/socket.h>
35
36 #include <err.h>
37 #include <stddef.h>
38 #include <stdio.h>
39 #include <string.h>
40 #include <unistd.h>
41
42 #include <netgraph/ng_message.h>
43 #include <netgraph/ng_socket.h>
44
45 #include "ngctl.h"
46
47 #define BUF_SIZE 8192
48
49 static int WriteCmd(int ac, char **av);
50
51 const struct ngcmd write_cmd = {
52 WriteCmd,
53 "write hook < -f file | byte ... >",
54 "Send a data packet down the hook named by \"hook\".",
55 "The data may be contained in a file, or may be described directly"
56 " on the command line by supplying a sequence of bytes.",
57 { "w" }
58 };
59
60 static int
WriteCmd(int ac,char ** av)61 WriteCmd(int ac, char **av)
62 {
63 u_int32_t sagbuf[64];
64 struct sockaddr_ng *sag = (struct sockaddr_ng *)sagbuf;
65 u_char buf[BUF_SIZE];
66 const char *hook;
67 size_t hooklen;
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 _Static_assert(sizeof(sagbuf) >=
78 offsetof(struct sockaddr_ng, sg_data) + NG_HOOKSIZ,
79 "sagbuf is too small for NG_HOOKSIZ");
80 hooklen = strlcpy(sag->sg_data, hook, NG_HOOKSIZ);
81 if (hooklen >= NG_HOOKSIZ) {
82 warnx("hook name \"%s\" too long", hook);
83 return (CMDRTN_ERROR);
84 }
85
86 /* Get data */
87 if (strcmp(av[2], "-f") == 0) {
88 if (ac != 4)
89 return (CMDRTN_USAGE);
90 if ((fp = fopen(av[3], "r")) == NULL) {
91 warn("can't read file \"%s\"", av[3]);
92 return (CMDRTN_ERROR);
93 }
94 if ((len = fread(buf, 1, sizeof(buf), fp)) == 0) {
95 if (ferror(fp))
96 warn("can't read file \"%s\"", av[3]);
97 else
98 warnx("file \"%s\" is empty", av[3]);
99 fclose(fp);
100 return (CMDRTN_ERROR);
101 }
102 fclose(fp);
103 } else {
104 for (i = 2, len = 0; i < ac && len < sizeof(buf); i++, len++) {
105 if (sscanf(av[i], "%i", &byte) != 1 ||
106 byte < -128 || byte > 255) {
107 warnx("invalid byte \"%s\"", av[i]);
108 return (CMDRTN_ERROR);
109 }
110 buf[len] = (u_char)byte;
111 }
112 if (len == 0)
113 return (CMDRTN_USAGE);
114 }
115
116 /* Send data */
117 sag->sg_len = 3 + hooklen;
118 sag->sg_family = AF_NETGRAPH;
119 if (sendto(dsock, buf, len, 0, (struct sockaddr *)sag,
120 sag->sg_len) < 0) {
121 warn("writing to hook \"%s\"", hook);
122 return (CMDRTN_ERROR);
123 }
124
125 /* Done */
126 return (CMDRTN_OK);
127 }
128