/*
 * main.c
 *
 * Copyright (c) 1996-1999 Whistle Communications, Inc.
 * All rights reserved.
 * 
 * Subject to the following obligations and disclaimer of warranty, use and
 * redistribution of this software, in source or object code forms, with or
 * without modifications are expressly permitted by Whistle Communications;
 * provided, however, that:
 * 1. Any and all reproductions of the source or object code must include the
 *    copyright notice above and the following disclaimer of warranties; and
 * 2. No rights are granted, in any manner or form, to use Whistle
 *    Communications, Inc. trademarks, including the mark "WHISTLE
 *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
 *    such appears in the above copyright notice or in the software.
 * 
 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
 * OF SUCH DAMAGE.
 *
 * $Whistle: main.c,v 1.9 1999/01/20 00:26:26 archie Exp $
 */

#include <sys/cdefs.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <unistd.h>
#include <sysexits.h>
#include <errno.h>
#include <err.h>
#include <stringlist.h>

#include <sys/types.h>
#include <sys/socket.h>
#include <sys/select.h>

#include <netgraph.h>

#define DEFAULT_HOOKNAME        "debug"
#define NG_SOCK_HOOK_NAME       "hook"

#define BUF_SIZE                (64 * 1024)

static void     WriteAscii(u_char * buf, int len);
static void     Usage(void);
static void     send_msgs(int, const char *);

static int outfd = STDOUT_FILENO;
static int infd = STDIN_FILENO;

static StringList *msgs;

/*
 * main()
 */
int
main(int ac, char *av[])
{
        struct ngm_connect ngc;
        const char *path = NULL;
        const char *hook = DEFAULT_HOOKNAME;
        int     csock, dsock;
        int     asciiFlag = 0;
        int     loopFlag = 0;
        int     noInput = 0;
        int     execFlag = 0;
        int     ch;

        if ((msgs = sl_init()) == NULL)
                err(EX_OSERR, NULL);

        /* Parse flags */
        while ((ch = getopt(ac, av, "aedlm:nsS")) != -1) {
                switch (ch) {
                case 'a':
                        asciiFlag = 1;
                        break;
                case 'd':
                        NgSetDebug(NgSetDebug(-1) + 1);
                        break;
                case 'e':
                        execFlag = 1;
                        break;
                case 'l':
                        loopFlag = 1;
                        break;
                case 'n':
                        noInput = 1;
                        break;
                case 'm':
                        if (sl_add(msgs, optarg) == -1)
                                err(EX_OSERR, NULL);
                        break;
                case 's':
                        outfd = STDIN_FILENO;
                        break;
                case 'S':
                        infd = STDOUT_FILENO;
                        break;
                case '?':
                default:
                        Usage();
                }
        }
        ac -= optind;
        av += optind;

        if (execFlag) {
                if (asciiFlag || loopFlag) {
                        fprintf(stderr, "conflicting options\n");
                        Usage();
                }
                if (ac < 3)
                        Usage();
                path = av[0];
                hook = av[1];
                av += 2;
                ac -= 2;
        } else {
                /* Get params */
                switch (ac) {
                case 2:
                        hook = av[1];
                        /* FALLTHROUGH */
                case 1:
                        path = av[0];
                        break;
                default:
                        Usage();
                }
        }

        /* Get sockets */
        if (NgMkSockNode(NULL, &csock, &dsock) < 0)
                errx(EX_OSERR, "can't get sockets");

        /* Connect socket node to specified node */
        snprintf(ngc.path, sizeof(ngc.path), "%s", path);
        snprintf(ngc.ourhook, sizeof(ngc.ourhook), NG_SOCK_HOOK_NAME);
        snprintf(ngc.peerhook, sizeof(ngc.peerhook), "%s", hook);

        if (NgSendMsg(csock, ".",
            NGM_GENERIC_COOKIE, NGM_CONNECT, &ngc, sizeof(ngc)) < 0)
                errx(EX_OSERR, "can't connect to node");

        if (execFlag) {
                /* move dsock to fd 0 and 1 */
                (void)close(0);
                (void)close(1);
                if (!noInput)
                        (void)dup2(dsock, 0);
                (void)dup2(dsock, 1);

                send_msgs(csock, path);

                /* try executing the program */
                (void)execv(av[0], av);
                err(EX_OSERR, "%s", av[0]);

        } else
                send_msgs(csock, path);

        /* Close standard input if not reading from it */
        if (noInput)
                fclose(stdin);

        /* Relay data */
        while (1) {
                fd_set  rfds;

                /* Setup bits */
                FD_ZERO(&rfds);
                if (!noInput)
                        FD_SET(infd, &rfds);
                FD_SET(dsock, &rfds);

                /* Wait for something to happen */
                if (select(FD_SETSIZE, &rfds, NULL, NULL, NULL) < 0)
                        err(EX_OSERR, "select");

                /* Check data from socket */
                if (FD_ISSET(dsock, &rfds)) {
                        char    buf[BUF_SIZE];
                        int     rl, wl;

                        /* Read packet from socket */
                        if ((rl = NgRecvData(dsock,
                            buf, sizeof(buf), NULL)) < 0)
                                err(EX_OSERR, "read(hook)");
                        if (rl == 0)
                                errx(EX_OSERR, "read EOF from hook?!");

                        /* Write packet to stdout */
                        if (asciiFlag)
                                WriteAscii((u_char *) buf, rl);
                        else if ((wl = write(outfd, buf, rl)) != rl) {
                                if (wl < 0) {
                                        err(EX_OSERR, "write(stdout)");
                                } else {
                                        errx(EX_OSERR,
                                            "stdout: read %d, wrote %d",
                                            rl, wl);
                                }
                        }
                        /* Loopback */
                        if (loopFlag) {
                                if (NgSendData(dsock, NG_SOCK_HOOK_NAME, buf, rl) < 0)
                                        err(EX_OSERR, "write(hook)");
                        }
                }

                /* Check data from stdin */
                if (FD_ISSET(infd, &rfds)) {
                        char    buf[BUF_SIZE];
                        int     rl;

                        /* Read packet from stdin */
                        if ((rl = read(infd, buf, sizeof(buf))) < 0)
                                err(EX_OSERR, "read(stdin)");
                        if (rl == 0)
                                errx(EX_OSERR, "EOF(stdin)");

                        /* Write packet to socket */
                        if (NgSendData(dsock, NG_SOCK_HOOK_NAME, buf, rl) < 0)
                                err(EX_OSERR, "write(hook)");
                }
        }
}

/*
 * Dump data in hex and ASCII form
 */
static void
WriteAscii(u_char *buf, int len)
{
        char    ch, sbuf[100];
        int     k, count;

        for (count = 0; count < len; count += 16) {
                snprintf(sbuf, sizeof(sbuf), "%04x:  ", count);
                for (k = 0; k < 16; k++)
                        if (count + k < len)
                                snprintf(sbuf + strlen(sbuf),
                                    sizeof(sbuf) - strlen(sbuf),
                                    "%02x ", buf[count + k]);
                        else
                                snprintf(sbuf + strlen(sbuf),
                                    sizeof(sbuf) - strlen(sbuf), "   ");
                snprintf(sbuf + strlen(sbuf), sizeof(sbuf) - strlen(sbuf), " ");
                for (k = 0; k < 16; k++)
                        if (count + k < len) {
                                ch = isprint(buf[count + k]) ?
                                    buf[count + k] : '.';
                                snprintf(sbuf + strlen(sbuf),
                                    sizeof(sbuf) - strlen(sbuf), "%c", ch);
                        } else
                                snprintf(sbuf + strlen(sbuf),
                                    sizeof(sbuf) - strlen(sbuf), " ");
                snprintf(sbuf + strlen(sbuf),
                    sizeof(sbuf) - strlen(sbuf), "\n");
                (void) write(outfd, sbuf, strlen(sbuf));
        }
        ch = '\n';
        write(outfd, &ch, 1);
}

/*
 * Display usage and exit
 */
static void
Usage(void)
{
        fprintf(stderr, "usage: nghook [-adlnsS] path [hookname]\n");
        fprintf(stderr, "   or: nghook -e [-n] [-m msg]* path hookname prog "
            "[args...]\n");
        exit(EX_USAGE);
}

/*
 * Send the messages to the node
 */
static void
send_msgs(int cs, const char *path)
{
        u_int   i;

        for (i = 0; i < msgs->sl_cur; i++)
                if (NgSendAsciiMsg(cs, path, "%s", msgs->sl_str[i]) == -1)
                        err(EX_OSERR, "sending message '%s'", msgs->sl_str[i]);
}