commands.c

来自「Linux下的socks的程序源程序,用于socks的代理服务」· C语言 代码 · 共 2,732 行 · 第 1/5 页

	if (net < 0) {
	    perror("telnet: socket");
	    return 0;
	}
#if	defined(IP_OPTIONS) && defined(IPPROTO_IP)
	if (srp && setsockopt(net, IPPROTO_IP, IP_OPTIONS, (char *)srp, srlen) < 0)
		perror("setsockopt (IP_OPTIONS)");
#endif
#if	defined(IPPROTO_IP) && defined(IP_TOS)
	{
# if	defined(HAS_GETTOS)
	    struct tosent *tp;
	    if (tos < 0 && (tp = gettosbyname("telnet", "tcp")))
		tos = tp->t_tos;
# endif
	    if (tos < 0)
		tos = 020;	/* Low Delay bit */
	    if (tos
		&& (setsockopt(net, IPPROTO_IP, IP_TOS, (char *)&tos, sizeof(int)) < 0)
		&& (errno != ENOPROTOOPT))
		    perror("telnet: setsockopt (IP_TOS) (ignored)");
	}
#endif	/* defined(IPPROTO_IP) && defined(IP_TOS) */

	if (debug && SetSockOpt(net, SOL_SOCKET, SO_DEBUG, 1) < 0) {
		perror("setsockopt (SO_DEBUG)");
	}

	if (connect(net, (struct sockaddr *)&sin, sizeof (sin)) < 0) {
#if	defined(h_addr)		/* In 4.3, this is a #define */
	    if (host && host->h_addr_list[1]) {
		int oerrno = errno;

		fprintf(stderr, "telnet: connect to address %s: ",
						inet_ntoa(sin.sin_addr));
		errno = oerrno;
		perror((char *)0);
		host->h_addr_list++;
		memcpy((caddr_t)&sin.sin_addr, 
			host->h_addr_list[0], host->h_length);
		(void) NetClose(net);
		continue;
	    }
#endif	/* defined(h_addr) */
	    perror("telnet: Unable to connect to remote host");
	    return 0;
	}
	connected++;
#if	defined(AUTHENTICATE)
	auth_encrypt_connect(connected);
#endif
    } while (connected == 0);
    cmdrc(hostp, hostname);
    if (autologin && user == NULL) {
	struct passwd *pw;

	user = getenv("USER");
	if (user == NULL ||
	    (pw = getpwnam(user)) && pw->pw_uid != getuid()) {
		if (pw = getpwuid(getuid()))
			user = pw->pw_name;
		else
			user = NULL;
	}
    }
    if (user) {
	env_define((unsigned char *)"USER", (unsigned char *)user);
	env_export((unsigned char *)"USER");
    }
    (void) call(status, "status", "notmuch", 0);
    if (setjmp(peerdied) == 0)
	telnet(user);
    (void) NetClose(net);
    ExitString("Connection closed by foreign host.\n",1);
    /*NOTREACHED*/
}

#define HELPINDENT (sizeof ("connect"))

static char
	openhelp[] =	"connect to a site",
	closehelp[] =	"close current connection",
	logouthelp[] =	"forcibly logout remote user and close the connection",
	quithelp[] =	"exit telnet",
	statushelp[] =	"print status information",
	helphelp[] =	"print help information",
	sendhelp[] =	"transmit special characters ('send ?' for more)",
	sethelp[] = 	"set operating parameters ('set ?' for more)",
	unsethelp[] = 	"unset operating parameters ('unset ?' for more)",
	togglestring[] ="toggle operating parameters ('toggle ?' for more)",
	slchelp[] =	"change state of special charaters ('slc ?' for more)",
	displayhelp[] =	"display operating parameters",
#if	defined(TN3270) && defined(unix)
	transcomhelp[] = "specify Unix command for transparent mode pipe",
#endif	/* defined(TN3270) && defined(unix) */
#if	defined(AUTHENTICATE)
	authhelp[] =	"turn on (off) authentication ('auth ?' for more)",
#endif
#if	defined(unix)
	zhelp[] =	"suspend telnet",
#endif	/* defined(unix) */
	shellhelp[] =	"invoke a subshell",
	envhelp[] =	"change environment variables ('environ ?' for more)",
	modestring[] = "try to enter line or character mode ('mode ?' for more)";

extern int	help();

static Command cmdtab[] = {
	{ "close",	closehelp,	bye,		1 },
	{ "logout",	logouthelp,	logout,		1 },
	{ "display",	displayhelp,	display,	0 },
	{ "mode",	modestring,	modecmd,	0 },
	{ "open",	openhelp,	tn,		0 },
	{ "quit",	quithelp,	quit,		0 },
	{ "send",	sendhelp,	sendcmd,	0 },
	{ "set",	sethelp,	setcmd,		0 },
	{ "unset",	unsethelp,	unsetcmd,	0 },
	{ "status",	statushelp,	status,		0 },
	{ "toggle",	togglestring,	toggle,		0 },
	{ "slc",	slchelp,	slccmd,		0 },
#if	defined(TN3270) && defined(unix)
	{ "transcom",	transcomhelp,	settranscom,	0 },
#endif	/* defined(TN3270) && defined(unix) */
#if	defined(AUTHENTICATE)
	{ "auth",	authhelp,	auth_cmd,	0 },
#endif
#if	defined(ENCRYPT)
	{ "encrypt",	encrypthelp,	encrypt_cmd,	0 },
#endif
#if	defined(unix)
	{ "z",		zhelp,		suspend,	0 },
#endif	/* defined(unix) */
#if	defined(TN3270)
	{ "!",		shellhelp,	shell,		1 },
#else
	{ "!",		shellhelp,	shell,		0 },
#endif
	{ "environ",	envhelp,	env_cmd,	0 },
	{ "?",		helphelp,	help,		0 },
	0
};

static char	crmodhelp[] =	"deprecated command -- use 'toggle crmod' instead";
static char	escapehelp[] =	"deprecated command -- use 'set escape' instead";

static Command cmdtab2[] = {
	{ "help",	0,		help,		0 },
	{ "escape",	escapehelp,	setescape,	0 },
	{ "crmod",	crmodhelp,	togcrmod,	0 },
	0
};


/*
 * Call routine with argc, argv set from args (terminated by 0).
 */

    /*VARARGS1*/
    static
call(va_alist)
    va_dcl
{
    va_list ap;
    typedef int (*intrtn_t)();
    intrtn_t routine;
    char *args[100];
    int argno = 0;

    va_start(ap);
    routine = (va_arg(ap, intrtn_t));
    while ((args[argno++] = va_arg(ap, char *)) != 0) {
	;
    }
    va_end(ap);
    return (*routine)(argno-1, args);
}


    static Command *
getcmd(name)
    char *name;
{
    Command *cm;

    if (cm = (Command *) genget(name, (char **) cmdtab, sizeof(Command)))
	return cm;
    return (Command *) genget(name, (char **) cmdtab2, sizeof(Command));
}

    void
command(top, tbuf, cnt)
    int top;
    char *tbuf;
    int cnt;
{
    register Command *c;

    setcommandmode();
    if (!top) {
	putchar('\n');
#if	defined(unix)
    } else {
	(void) signal(SIGINT, SIG_DFL);
	(void) signal(SIGQUIT, SIG_DFL);
#endif	/* defined(unix) */
    }
    for (;;) {
	if (rlogin == _POSIX_VDISABLE)
		printf("%s> ", prompt);
	if (tbuf) {
	    register char *cp;
	    cp = line;
	    while (cnt > 0 && (*cp++ = *tbuf++) != '\n')
		cnt--;
	    tbuf = 0;
	    if (cp == line || *--cp != '\n' || cp == line)
		goto getline;
	    *cp = '\0';
	    if (rlogin == _POSIX_VDISABLE)
	        printf("%s\n", line);
	} else {
	getline:
	    if (rlogin != _POSIX_VDISABLE)
		printf("%s> ", prompt);
	    if (fgets(line, sizeof(line), stdin) == NULL) {
		if (feof(stdin) || ferror(stdin)) {
		    (void) quit();
		    /*NOTREACHED*/
		}
		break;
	    }
	}
	if (line[0] == 0)
	    break;
	makeargv();
	if (margv[0] == 0) {
	    break;
	}
	c = getcmd(margv[0]);
	if (Ambiguous(c)) {
	    printf("?Ambiguous command\n");
	    continue;
	}
	if (c == 0) {
	    printf("?Invalid command\n");
	    continue;
	}
	if (c->needconnect && !connected) {
	    printf("?Need to be connected first.\n");
	    continue;
	}
	if ((*c->handler)(margc, margv)) {
	    break;
	}
    }
    if (!top) {
	if (!connected) {
	    longjmp(toplevel, 1);
	    /*NOTREACHED*/
	}
#if	defined(TN3270)
	if (shell_active == 0) {
	    setconnmode(0);
	}
#else	/* defined(TN3270) */
	setconnmode(0);
#endif	/* defined(TN3270) */
    }
}

/*
 * Help command.
 */
	static
help(argc, argv)
	int argc;
	char *argv[];
{
	register Command *c;

	if (argc == 1) {
		printf("Commands may be abbreviated.  Commands are:\n\n");
		for (c = cmdtab; c->name; c++)
			if (c->help) {
				printf("%-*s\t%s\n", HELPINDENT, c->name,
								    c->help);
			}
		return 0;
	}
	while (--argc > 0) {
		register char *arg;
		arg = *++argv;
		c = getcmd(arg);
		if (Ambiguous(c))
			printf("?Ambiguous help command %s\n", arg);
		else if (c == (Command *)0)
			printf("?Invalid help command %s\n", arg);
		else
			printf("%s\n", c->help);
	}
	return 0;
}

static char *rcname = 0;
static char rcbuf[128];

cmdrc(m1, m2)
	char *m1, *m2;
{
    register Command *c;
    FILE *rcfile;
    int gotmachine = 0;
    int l1 = strlen(m1);
    int l2 = strlen(m2);
    char m1save[64];

    if (skiprc)
	return;

    strcpy(m1save, m1);
    m1 = m1save;

    if (rcname == 0) {
	rcname = getenv("HOME");
	if (rcname)
	    strcpy(rcbuf, rcname);
	else
	    rcbuf[0] = '\0';
	strcat(rcbuf, "/.telnetrc");
	rcname = rcbuf;
    }

    if ((rcfile = fopen(rcname, "r")) == 0) {
	return;
    }

    for (;;) {
	if (fgets(line, sizeof(line), rcfile) == NULL)
	    break;
	if (line[0] == 0)
	    break;
	if (line[0] == '#')
	    continue;
	if (gotmachine) {
	    if (!isspace(line[0]))
		gotmachine = 0;
	}
	if (gotmachine == 0) {
	    if (isspace(line[0]))
		continue;
	    if (strncasecmp(line, m1, l1) == 0)
		strncpy(line, &line[l1], sizeof(line) - l1);
	    else if (strncasecmp(line, m2, l2) == 0)
		strncpy(line, &line[l2], sizeof(line) - l2);
	    else if (strncasecmp(line, "DEFAULT", 7) == 0)
		strncpy(line, &line[7], sizeof(line) - 7);
	    else
		continue;
	    if (line[0] != ' ' && line[0] != '\t' && line[0] != '\n')
		continue;
	    gotmachine = 1;
	}
	makeargv();
	if (margv[0] == 0)
	    continue;
	c = getcmd(margv[0]);
	if (Ambiguous(c)) {
	    printf("?Ambiguous command: %s\n", margv[0]);
	    continue;
	}
	if (c == 0) {
	    printf("?Invalid command: %s\n", margv[0]);
	    continue;
	}
	/*
	 * This should never happen...
	 */
	if (c->needconnect && !connected) {
	    printf("?Need to be connected first for %s.\n", margv[0]);
	    continue;
	}
	(*c->handler)(margc, margv);
    }
    fclose(rcfile);
}

#if	defined(IP_OPTIONS) && defined(IPPROTO_IP)

/*
 * Source route is handed in as
 *	[!]@hop1@hop2...[@|:]dst
 * If the leading ! is present, it is a
 * strict source route, otherwise it is
 * assmed to be a loose source route.
 *
 * We fill in the source route option as
 *	hop1,hop2,hop3...dest
 * and return a pointer to hop1, which will
 * be the address to connect() to.
 *
 * Arguments:
 *	arg:	pointer to route list to decipher
 *
 *	cpp: 	If *cpp is not equal to NULL, this is a
 *		pointer to a pointer to a character array
 *		that should be filled in with the option.
 *
 *	lenp:	pointer to an integer that contains the
 *		length of *cpp if *cpp != NULL.
 *
 * Return values:
 *
 *	Returns the address of the host to connect to.  If the
 *	return value is -1, there was a syntax error in the
 *	option, either unknown characters, or too many hosts.
 *	If the return value is 0, one of the hostnames in the
 *	path is unknown, and *cpp is set to point to the bad
 *	hostname.
 *
 *	*cpp:	If *cpp was equal to NULL, it will be filled
 *		in with a pointer to our static area that has
 *		the option filled in.  This will be 32bit aligned.
 * 
 *	*lenp:	This will be filled in with how long the option
 *		pointed to by *cpp is.
 *	
 */
	u_int32
sourceroute(arg, cpp, lenp)
	char	*arg;
	char	**cpp;
	int	*lenp;
{
	static char lsr[44];
	char *cp, *cp2, *lsrp, *lsrep;
	register int tmp;
	struct in_addr sin_addr;
	register struct hostent *host = 0;
	register char c;

	/*
	 * Verify the arguments, and make sure we have
	 * at least 7 bytes for the option.
	 */
	if (cpp == NULL || lenp == NULL)
		/* return((u_int32)-1); */
		return(INADDR_NONE /* H.Naef, nexos ag */);
	if (*cpp != NULL && *lenp < 7)
		/* return((u_int32)-1); */
		return(INADDR_NONE /* H.Naef, nexos ag */);
	/*
	 * Decide whether we have a buffer passed to us,
	 * or if we need to use our own static buffer.
	 */
	if (*cpp) {
		lsrp = *cpp;
		lsrep = lsrp + *lenp;
	} else {
		*cpp = lsrp = lsr;
		lsrep = lsrp + 44;
	}

	cp = arg;

	/*
	 * Next, decide whether we have a loose source
	 * route or a strict source route, and fill in
	 * the begining of the option.
	 */
	if (*cp == '!') {
		cp++;
		*lsrp++ = IPOPT_SSRR;
	} else
		*lsrp++ = IPOPT_LSRR;

	if (*cp != '@')
		/* return((u_int32)-1); */
		return(INADDR_NONE /* H.Naef, nexos ag */);

	lsrp++;		/* skip over length, we'll fill it in later */
	*lsrp++ = 4;

	cp++;

	sin_addr.s_addr = 0;

	for (c = 0;;) {
		if (c == ':')
			cp2 = 0;
		else for (cp2 = cp; c = *cp2; cp2++) {
			if (c == ',') {
				*cp2++ = '\0';
				if (*cp2 == '@')
					cp2++;
			} else if (c == '@') {
				*cp2++ = '\0';
			} else if (c == ':') {
				*cp2++ = '\0';
			} else
				continue;
			break;
		}
		if (!c)
			cp2 = 0;

		/* if ((tmp = inet_addr(cp)) != -1) { */
		if ((tmp = inet_addr(cp)) != INADDR_NONE /* H.Naef, nexos ag */) {
			sin_addr.s_addr = tmp;
		} else if (host = gethostbyname(cp)) {
#if	defined(h_addr)
			memcpy((caddr_t)&sin_addr,
				host->h_addr_list[0], host->h_length);
#else
			memcpy((caddr_t)&sin_addr, host->h_addr, host->h_length);
#endif
		} else {
			*cpp = cp;
			return(0);
		}
		memcpy(lsrp, (char *)&sin_addr, 4);
		lsrp += 4;
		if (cp2)
			cp = cp2;
		else
			break;
		/*
		 * Check to make sure there is space for next address
		 */
		if (lsrp + 4 > lsrep)
			/* return((u_int32)-1); */
			return(INADDR_NONE /* H.Naef, nexos ag */);
	}
	if ((*(*cpp+IPOPT_OLEN) = lsrp - *cpp) <= 7) {
		*cpp = 0;
		*lenp = 0;
		/* return((u_int32)-1); */
		return(INADDR_NONE /* H.Naef, nexos ag */);
	}
	*lsrp++ = IPOPT_NOP; /* 32 bit word align it */
	*lenp = lsrp - *cpp;
	return(sin_addr.s_addr);
}
#endif