/*
 * Copyright (c) 1995 Danny Gasparovski.
 *
 * Please read the file COPYRIGHT for the
 * terms and conditions of the copyright.
 */

#define WANT_SYS_IOCTL_H
#include <slirp.h>

u_int curtime, time_fasttimo, last_slowtimo, detach_time;
u_int detach_wait = 600000; /* 10 minutes */

#if 0
int x_port = -1;
int x_display = 0;
int x_screen = 0;

int
show_x(buff, inso)
	char *buff;
	struct socket *inso;
{
	if (x_port < 0) {
		lprint("X Redir: X not being redirected.\r\n");
	} else {
		lprint("X Redir: In sh/bash/zsh/etc. type: DISPLAY=%s:%d.%d; export DISPLAY\r\n",
		      inet_ntoa(our_addr), x_port, x_screen);
		lprint("X Redir: In csh/tcsh/etc. type:    setenv DISPLAY %s:%d.%d\r\n",
		      inet_ntoa(our_addr), x_port, x_screen);
		if (x_display)
		   lprint("X Redir: Redirecting to display %d\r\n", x_display);
	}
	
	return CFG_OK;
}


/*
 * XXX Allow more than one X redirection?
 */
void
redir_x(inaddr, start_port, display, screen)
	u_int32_t inaddr;
	int start_port;
	int display;
	int screen;
{
	int i;
	
	if (x_port >= 0) {
		lprint("X Redir: X already being redirected.\r\n");
		show_x(0, 0);
	} else {
		for (i = 6001 + (start_port-1); i <= 6100; i++) {
			if (solisten(htons(i), inaddr, htons(6000 + display), 0)) {
				/* Success */
				x_port = i - 6000;
				x_display = display;
				x_screen = screen;
				show_x(0, 0);
				return;
			}
		}
		lprint("X Redir: Error: Couldn't redirect a port for X. Weird.\r\n");
	}
}
#endif

#ifndef HAVE_INET_ATON
int inet_aton(cp, ia) const char *cp;
struct in_addr *ia;
{
    u_int32_t addr = inet_addr(cp);
    if (addr == 0xffffffff)
        return 0;
    ia->s_addr = addr;
    return 1;
}
#endif

/*
 * Get our IP address and put it in our_addr
 */
void getouraddr()
{
    char buff[256];
    struct hostent *he;

    if (gethostname(buff, 256) < 0)
        return;

    if ((he = gethostbyname(buff)) == NULL)
        return;

    our_addr = *(struct in_addr *)he->h_addr;
}

#if SIZEOF_CHAR_P == 8

struct quehead_32 {
    u_int32_t qh_link;
    u_int32_t qh_rlink;
};

inline void insque_32(a, b) void *a;
void *b;
{
    register struct quehead_32 *element = (struct quehead_32 *)a;
    register struct quehead_32 *head = (struct quehead_32 *)b;
    element->qh_link = head->qh_link;
    head->qh_link = (u_int32_t)element;
    element->qh_rlink = (u_int32_t)head;
    ((struct quehead_32 *)(element->qh_link))->qh_rlink = (u_int32_t)element;
}

inline void remque_32(a) void *a;
{
    register struct quehead_32 *element = (struct quehead_32 *)a;
    ((struct quehead_32 *)(element->qh_link))->qh_rlink = element->qh_rlink;
    ((struct quehead_32 *)(element->qh_rlink))->qh_link = element->qh_link;
    element->qh_rlink = 0;
}

#endif /* SIZEOF_CHAR_P == 8 */

struct quehead {
    struct quehead *qh_link;
    struct quehead *qh_rlink;
};

inline void insque(a, b) void *a, *b;
{
    register struct quehead *element = (struct quehead *)a;
    register struct quehead *head = (struct quehead *)b;
    element->qh_link = head->qh_link;
    head->qh_link = (struct quehead *)element;
    element->qh_rlink = (struct quehead *)head;
    ((struct quehead *)(element->qh_link))->qh_rlink =
        (struct quehead *)element;
}

inline void remque(a) void *a;
{
    register struct quehead *element = (struct quehead *)a;
    ((struct quehead *)(element->qh_link))->qh_rlink = element->qh_rlink;
    ((struct quehead *)(element->qh_rlink))->qh_link = element->qh_link;
    element->qh_rlink = NULL;
    /*  element->qh_link = NULL;  TCP FIN1 crashes if you do this.  Why ? */
}

/* #endif */


int add_exec(ex_ptr, do_pty, exec, addr, port) struct ex_list **ex_ptr;
int do_pty;
char *exec;
int addr;
int port;
{
    struct ex_list *tmp_ptr;

    /* First, check if the port is "bound" */
    for (tmp_ptr = *ex_ptr; tmp_ptr; tmp_ptr = tmp_ptr->ex_next) {
        if (port == tmp_ptr->ex_fport && addr == tmp_ptr->ex_addr)
            return -1;
    }

    tmp_ptr = *ex_ptr;
    *ex_ptr = (struct ex_list *)malloc(sizeof(struct ex_list));
    (*ex_ptr)->ex_fport = port;
    (*ex_ptr)->ex_addr = addr;
    (*ex_ptr)->ex_pty = do_pty;
    (*ex_ptr)->ex_exec = strdup(exec);
    (*ex_ptr)->ex_next = tmp_ptr;
    return 0;
}

#ifndef HAVE_STRERROR

/*
 * For systems with no strerror
 */

extern int sys_nerr;
extern char *sys_errlist[];

char *strerror(error) int error;
{
    if (error < sys_nerr)
        return sys_errlist[error];
    else
        return "Unknown error.";
}

#endif


#ifdef _WIN32

int fork_exec(so, ex, do_pty) struct socket *so;
char *ex;
int do_pty;
{
    /* not implemented */
    return 0;
}

#else

int slirp_openpty(amaster, aslave) int *amaster, *aslave;
{
    register int master, slave;

#ifdef HAVE_GRANTPT
    char *ptr;

    if ((master = open("/dev/ptmx", O_RDWR)) < 0 || grantpt(master) < 0 ||
        unlockpt(master) < 0 || (ptr = ptsname(master)) == NULL) {
        close(master);
        return -1;
    }

    if ((slave = open(ptr, O_RDWR)) < 0 || ioctl(slave, I_PUSH, "ptem") < 0 ||
        ioctl(slave, I_PUSH, "ldterm") < 0 ||
        ioctl(slave, I_PUSH, "ttcompat") < 0) {
        close(master);
        close(slave);
        return -1;
    }

    *amaster = master;
    *aslave = slave;
    return 0;

#else

    static char line[] = "/dev/ptyXX";
    register const char *cp1, *cp2;

    for (cp1 = "pqrsPQRS"; *cp1; cp1++) {
        line[8] = *cp1;
        for (cp2 = "0123456789abcdefghijklmnopqrstuv"; *cp2; cp2++) {
            line[9] = *cp2;
            if ((master = open(line, O_RDWR, 0)) == -1) {
                if (errno == ENOENT)
                    return (-1); /* out of ptys */
            } else {
                line[5] = 't';
                /* These will fail */
                (void)chown(line, getuid(), 0);
                (void)chmod(line, S_IRUSR | S_IWUSR | S_IWGRP);
#ifdef HAVE_REVOKE
                (void)revoke(line);
#endif
                if ((slave = open(line, O_RDWR, 0)) != -1) {
                    *amaster = master;
                    *aslave = slave;
                    return 0;
                }
                (void)close(master);
                line[5] = 'p';
            }
        }
    }
    errno = ENOENT; /* out of ptys */
    return (-1);
#endif
}

/*
 * XXX This is ugly
 * We create and bind a socket, then fork off to another
 * process, which connects to this socket, after which we
 * exec the wanted program.  If something (strange) happens,
 * the accept() call could block us forever.
 *
 * do_pty = 0   Fork/exec inetd style
 * do_pty = 1   Fork/exec using slirp.telnetd
 * do_ptr = 2   Fork/exec using pty
 */
int fork_exec(so, ex, do_pty) struct socket *so;
char *ex;
int do_pty;
{
    int s;
    struct sockaddr_in addr;
    int addrlen = sizeof(addr);
    int opt;
    int master;
    char *argv[256];
#if 0
	char buff[256];
#endif
    /* don't want to clobber the original */
    char *bptr;
    char *curarg;
    int c, i;

    DEBUG_CALL("fork_exec");
    DEBUG_ARG("so = %lx", (long)so);
    DEBUG_ARG("ex = %lx", (long)ex);
    DEBUG_ARG("do_pty = %lx", (long)do_pty);

    if (do_pty == 2) {
        if (slirp_openpty(&master, &s) == -1) {
            lprint("Error: openpty failed: %s\n", strerror(errno));
            return 0;
        }
    } else {
        addr.sin_family = AF_INET;
        addr.sin_port = 0;
        addr.sin_addr.s_addr = INADDR_ANY;

        if ((s = socket(AF_INET, SOCK_STREAM, 0)) < 0 ||
            bind(s, (struct sockaddr *)&addr, addrlen) < 0 ||
            listen(s, 1) < 0) {
            lprint("Error: inet socket: %s\n", strerror(errno));
            closesocket(s);

            return 0;
        }
    }

    switch (fork()) {
    case -1:
        lprint("Error: fork failed: %s\n", strerror(errno));
        close(s);
        if (do_pty == 2)
            close(master);
        return 0;

    case 0:
        /* Set the DISPLAY */
        if (do_pty == 2) {
            (void)close(master);
#ifdef TIOCSCTTY /* XXXXX */
            (void)setsid();
            ioctl(s, TIOCSCTTY, (char *)NULL);
#endif
        } else {
            getsockname(s, (struct sockaddr *)&addr, &addrlen);
            close(s);
            /*
             * Connect to the socket
             * XXX If any of these fail, we're in trouble!
             */
            s = socket(AF_INET, SOCK_STREAM, 0);
            addr.sin_addr = loopback_addr;
            connect(s, (struct sockaddr *)&addr, addrlen);
        }

#if 0
		if (x_port >= 0) {
#ifdef HAVE_SETENV
			sprintf(buff, "%s:%d.%d", inet_ntoa(our_addr), x_port, x_screen);
			setenv("DISPLAY", buff, 1);
#else
			sprintf(buff, "DISPLAY=%s:%d.%d", inet_ntoa(our_addr), x_port, x_screen);
			putenv(buff);
#endif
		}
#endif
        dup2(s, 0);
        dup2(s, 1);
        dup2(s, 2);
        for (s = 3; s <= 255; s++)
            close(s);

        i = 0;
        bptr = strdup(ex); /* No need to free() this */
        if (do_pty == 1) {
            /* Setup "slirp.telnetd -x" */
            argv[i++] = "slirp.telnetd";
            argv[i++] = "-x";
            argv[i++] = bptr;
        } else
            do {
                /* Change the string into argv[] */
                curarg = bptr;
                while (*bptr != ' ' && *bptr != (char)0)
                    bptr++;
                c = *bptr;
                *bptr++ = (char)0;
                argv[i++] = strdup(curarg);
            } while (c);

        argv[i] = 0;
        execvp(argv[0], argv);

        /* Ooops, failed, let's tell the user why */
        {
            char buff[256];

            sprintf(buff, "Error: execvp of %s failed: %s\n", argv[0],
                    strerror(errno));
            write(2, buff, strlen(buff) + 1);
        }
        close(0);
        close(1);
        close(2); /* XXX */
        exit(1);

    default:
        if (do_pty == 2) {
            close(s);
            so->s = master;
        } else {
            /*
             * XXX this could block us...
             * XXX Should set a timer here, and if accept() doesn't
             * return after X seconds, declare it a failure
             * The only reason this will block forever is if socket()
             * of connect() fail in the child process
             */
            so->s = accept(s, (struct sockaddr *)&addr, &addrlen);
            closesocket(s);
            opt = 1;
            setsockopt(so->s, SOL_SOCKET, SO_REUSEADDR, (char *)&opt,
                       sizeof(int));
            opt = 1;
            setsockopt(so->s, SOL_SOCKET, SO_OOBINLINE, (char *)&opt,
                       sizeof(int));
        }
        fd_nonblock(so->s);

        /* Append the telnet options now */
        if (so->so_m != 0 && do_pty == 1) {
            sbappend(so, so->so_m);
            so->so_m = 0;
        }

        return 1;
    }
}
#endif

#ifndef HAVE_STRDUP
char *strdup(str) const char *str;
{
    char *bptr;

    bptr = (char *)malloc(strlen(str) + 1);
    strcpy(bptr, str);

    return bptr;
}
#endif

#if 0
void
snooze_hup(num)
	int num;
{
	int s, ret;
#ifndef NO_UNIX_SOCKETS
	struct sockaddr_un sock_un;
#endif
	struct sockaddr_in sock_in;
	char buff[256];
	
	ret = -1;
	if (slirp_socket_passwd) {
		s = socket(AF_INET, SOCK_STREAM, 0);
		if (s < 0)
		   slirp_exit(1);
		sock_in.sin_family = AF_INET;
		sock_in.sin_addr.s_addr = slirp_socket_addr;
		sock_in.sin_port = htons(slirp_socket_port);
		if (connect(s, (struct sockaddr *)&sock_in, sizeof(sock_in)) != 0)
		   slirp_exit(1); /* just exit...*/
		sprintf(buff, "kill %s:%d", slirp_socket_passwd, slirp_socket_unit);
		write(s, buff, strlen(buff)+1);
	}
#ifndef NO_UNIX_SOCKETS
	  else {
		s = socket(AF_UNIX, SOCK_STREAM, 0);
		if (s < 0)
		   slirp_exit(1);
		sock_un.sun_family = AF_UNIX;
		strcpy(sock_un.sun_path, socket_path);
		if (connect(s, (struct sockaddr *)&sock_un,
			      sizeof(sock_un.sun_family) + sizeof(sock_un.sun_path)) != 0)
		   slirp_exit(1);
		sprintf(buff, "kill none:%d", slirp_socket_unit);
		write(s, buff, strlen(buff)+1);
	}
#endif
	slirp_exit(0);
}
	
	
void
snooze()
{
	sigset_t s;
	int i;
	
	/* Don't need our data anymore */
	/* XXX This makes SunOS barf */
/*	brk(0); */
	
	/* Close all fd's */
	for (i = 255; i >= 0; i--)
	   close(i);
	
	signal(SIGQUIT, slirp_exit);
	signal(SIGHUP, snooze_hup);
	sigemptyset(&s);
	
	/* Wait for any signal */
	sigsuspend(&s);
	
	/* Just in case ... */
	exit(255);
}

void
relay(s)
	int s;
{
	char buf[8192];
	int n;
	fd_set readfds;
	struct ttys *ttyp;
	
	/* Don't need our data anymore */
	/* XXX This makes SunOS barf */
/*	brk(0); */
	
	signal(SIGQUIT, slirp_exit);
	signal(SIGHUP, slirp_exit);
        signal(SIGINT, slirp_exit);
	signal(SIGTERM, slirp_exit);
	
	/* Fudge to get term_raw and term_restore to work */
	if (NULL == (ttyp = tty_attach (0, slirp_tty))) {
         lprint ("Error: tty_attach failed in misc.c:relay()\r\n");
         slirp_exit (1);
    }
	ttyp->fd = 0;
	ttyp->flags |= TTY_CTTY;
	term_raw(ttyp);
	
	while (1) {
		FD_ZERO(&readfds);
		
		FD_SET(0, &readfds);
		FD_SET(s, &readfds);
		
		n = select(s+1, &readfds, (fd_set *)0, (fd_set *)0, (struct timeval *)0);
		
		if (n <= 0)
		   slirp_exit(0);
		
		if (FD_ISSET(0, &readfds)) {
			n = read(0, buf, 8192);
			if (n <= 0)
			   slirp_exit(0);
			n = writen(s, buf, n);
			if (n <= 0)
			   slirp_exit(0);
		}
		
		if (FD_ISSET(s, &readfds)) {
			n = read(s, buf, 8192);
			if (n <= 0)
			   slirp_exit(0);
			n = writen(0, buf, n);
			if (n <= 0)
			   slirp_exit(0);
		}
	}
	
	/* Just in case.... */
	exit(1);
}
#endif

int(*lprint_print) _P((void *, const char *, va_list));
char *lprint_ptr, *lprint_ptr2, **lprint_arg;

void
#ifdef __STDC__
lprint(const char *format, ...)
#else
    lprint(va_alist) va_dcl
#endif
{
    va_list args;

#ifdef __STDC__
    va_start(args, format);
#else
    char *format;
    va_start(args);
    format = va_arg(args, char *);
#endif
#if 0
	/* If we're printing to an sbuf, make sure there's enough room */
	/* XXX +100? */
	if (lprint_sb) {
		if ((lprint_ptr - lprint_sb->sb_wptr) >=
		    (lprint_sb->sb_datalen - (strlen(format) + 100))) {
			int deltaw = lprint_sb->sb_wptr - lprint_sb->sb_data;
			int deltar = lprint_sb->sb_rptr - lprint_sb->sb_data;
			int deltap = lprint_ptr -         lprint_sb->sb_data;
			                        
			lprint_sb->sb_data = (char *)realloc(lprint_sb->sb_data,
							     lprint_sb->sb_datalen + TCP_SNDSPACE);
			
			/* Adjust all values */
			lprint_sb->sb_wptr = lprint_sb->sb_data + deltaw;
			lprint_sb->sb_rptr = lprint_sb->sb_data + deltar;
			lprint_ptr =         lprint_sb->sb_data + deltap;
			
			lprint_sb->sb_datalen += TCP_SNDSPACE;
		}
	}
#endif
    if (lprint_print)
        lprint_ptr += (*lprint_print)(*lprint_arg, format, args);

    /* Check if they want output to be logged to file as well */
    if (lfd) {
        /*
         * Remove \r's
         * otherwise you'll get ^M all over the file
         */
        int len = strlen(format);
        char *bptr1, *bptr2;

        bptr1 = bptr2 = strdup(format);

        while (len--) {
            if (*bptr1 == '\r')
                memcpy(bptr1, bptr1 + 1, len + 1);
            else
                bptr1++;
        }
        vfprintf(lfd, bptr2, args);
        free(bptr2);
    }
    va_end(args);
}

void add_emu(buff) char *buff;
{
    u_int lport, fport;
    u_int8_t tos = 0, emu = 0;
    char buff1[256], buff2[256], buff4[128];
    char *buff3 = buff4;
    struct emu_t *emup;
    struct socket *so;

    if (sscanf(buff, "%256s %256s", buff2, buff1) != 2) {
        lprint("Error: Bad arguments\r\n");
        return;
    }

    if (sscanf(buff1, "%d:%d", &lport, &fport) != 2) {
        lport = 0;
        if (sscanf(buff1, "%d", &fport) != 1) {
            lprint("Error: Bad first argument\r\n");
            return;
        }
    }

    if (sscanf(buff2, "%128[^:]:%128s", buff1, buff3) != 2) {
        buff3 = 0;
        if (sscanf(buff2, "%256s", buff1) != 1) {
            lprint("Error: Bad second argument\r\n");
            return;
        }
    }

    if (buff3) {
        if (strcmp(buff3, "lowdelay") == 0)
            tos = IPTOS_LOWDELAY;
        else if (strcmp(buff3, "throughput") == 0)
            tos = IPTOS_THROUGHPUT;
        else {
            lprint("Error: Expecting \"lowdelay\"/\"throughput\"\r\n");
            return;
        }
    }

    if (strcmp(buff1, "ftp") == 0)
        emu = EMU_FTP;
    else if (strcmp(buff1, "irc") == 0)
        emu = EMU_IRC;
    else if (strcmp(buff1, "none") == 0)
        emu = EMU_NONE; /* ie: no emulation */
    else {
        lprint("Error: Unknown service\r\n");
        return;
    }

    /* First, check that it isn't already emulated */
    for (emup = tcpemu; emup; emup = emup->next) {
        if (emup->lport == lport && emup->fport == fport) {
            lprint("Error: port already emulated\r\n");
            return;
        }
    }

    /* link it */
    emup = (struct emu_t *)malloc(sizeof(struct emu_t));
    emup->lport = (u_int16_t)lport;
    emup->fport = (u_int16_t)fport;
    emup->tos = tos;
    emup->emu = emu;
    emup->next = tcpemu;
    tcpemu = emup;

    /* And finally, mark all current sessions, if any, as being emulated */
    for (so = tcb.so_next; so != &tcb; so = so->so_next) {
        if ((lport && lport == ntohs(so->so_lport)) ||
            (fport && fport == ntohs(so->so_fport))) {
            if (emu)
                so->so_emu = emu;
            if (tos)
                so->so_iptos = tos;
        }
    }

    lprint("Adding emulation for %s to port %d/%d\r\n", buff1, emup->lport,
           emup->fport);
}

#ifdef BAD_SPRINTF

#undef vsprintf
#undef sprintf

/*
 * Some BSD-derived systems have a sprintf which returns char *
 */

int vsprintf_len(string, format, args) char *string;
const char *format;
va_list args;
{
    vsprintf(string, format, args);
    return strlen(string);
}

int
#ifdef __STDC__
sprintf_len(char *string, const char *format, ...)
#else
    sprintf_len(va_alist) va_dcl
#endif
{
    va_list args;
#ifdef __STDC__
    va_start(args, format);
#else
    char *string;
    char *format;
    va_start(args);
    string = va_arg(args, char *);
    format = va_arg(args, char *);
#endif
    vsprintf(string, format, args);
    return strlen(string);
}

#endif

void u_sleep(usec) int usec;
{
    struct timeval t;
    fd_set fdset;

    FD_ZERO(&fdset);

    t.tv_sec = 0;
    t.tv_usec = usec * 1000;

    select(0, &fdset, &fdset, &fdset, &t);
}

/*
 * Set fd blocking and non-blocking
 */

void fd_nonblock(fd) int fd;
{
#ifdef FIONBIO
    int opt = 1;

    ioctlsocket(fd, FIONBIO, &opt);
#else
    int opt;

    opt = fcntl(fd, F_GETFL, 0);
    opt |= O_NONBLOCK;
    fcntl(fd, F_SETFL, opt);
#endif
}

void fd_block(fd) int fd;
{
#ifdef FIONBIO
    int opt = 0;

    ioctlsocket(fd, FIONBIO, &opt);
#else
    int opt;

    opt = fcntl(fd, F_GETFL, 0);
    opt &= ~O_NONBLOCK;
    fcntl(fd, F_SETFL, opt);
#endif
}


#if 0
/*
 * invoke RSH
 */
int
rsh_exec(so,ns, user, host, args)
	struct socket *so;
	struct socket *ns;
	char *user;
	char *host;
	char *args;
{
	int fd[2];
	int fd0[2];
	int s;
	char buff[256];
	
	DEBUG_CALL("rsh_exec");
	DEBUG_ARG("so = %lx", (long)so);
	
	if (pipe(fd)<0) {
          lprint("Error: pipe failed: %s\n", strerror(errno));
          return 0;
	}
/* #ifdef HAVE_SOCKETPAIR */
#if 1
        if (socketpair(PF_UNIX,SOCK_STREAM,0, fd0) == -1) {
          close(fd[0]);
          close(fd[1]);
          lprint("Error: openpty failed: %s\n", strerror(errno));
          return 0;
        }
#else
        if (slirp_openpty(&fd0[0], &fd0[1]) == -1) {
          close(fd[0]);
          close(fd[1]);
          lprint("Error: openpty failed: %s\n", strerror(errno));
          return 0;
        }
#endif
	
	switch(fork()) {
	 case -1:
           lprint("Error: fork failed: %s\n", strerror(errno));
           close(fd[0]);
           close(fd[1]);
           close(fd0[0]);
           close(fd0[1]);
           return 0;
           
	 case 0:
           close(fd[0]);
           close(fd0[0]);
           
		/* Set the DISPLAY */
           if (x_port >= 0) {
#ifdef HAVE_SETENV
             sprintf(buff, "%s:%d.%d", inet_ntoa(our_addr), x_port, x_screen);
             setenv("DISPLAY", buff, 1);
#else
             sprintf(buff, "DISPLAY=%s:%d.%d", inet_ntoa(our_addr), x_port, x_screen);
             putenv(buff);
#endif
           }
           
           dup2(fd0[1], 0);
           dup2(fd0[1], 1);
           dup2(fd[1], 2);
           for (s = 3; s <= 255; s++)
             close(s);
           
           execlp("rsh","rsh","-l", user, host, args, NULL);
           
           /* Ooops, failed, let's tell the user why */
           
           sprintf(buff, "Error: execlp of %s failed: %s\n", 
                   "rsh", strerror(errno));
           write(2, buff, strlen(buff)+1);
           close(0); close(1); close(2); /* XXX */
           exit(1);
           
        default:
          close(fd[1]);
          close(fd0[1]);
          ns->s=fd[0];
          so->s=fd0[0];
          
          return 1;
	}
}
#endif