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 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