ntpdc.c

网络时间协议NTP 源码 版本v4.2.0b 该源码用于linux平台下

		    continue;
		if (strncmp(str, cl->keyword, (unsigned)clen) == 0) {
			/*
			 * Could be extact match, could be approximate.
			 * Is exact if the length of the keyword is the
			 * same as the str.
			 */
			if (*((cl->keyword) + clen) == '\0') {
				*cmd = cl;
				return 1;
			}
			nmatch++;
			nearmatch = cl;
		}
	}

				/*
				 * See if there is more to do.  If so, go again.  Sorry about the
				 * goto, too much looking at BSD sources...
				 */
	if (clist == clist1 && clist2 != 0) {
		clist = clist2;
		goto again;
	}

				/*
				 * If we got extactly 1 near match, use it, else return number
				 * of matches.
				 */
	if (nmatch == 1) {
		*cmd = nearmatch;
		return 1;
	}
	return nmatch;
}


/*
 * getarg - interpret an argument token
 *
 * return:	 0 - failure
 *		 1 - success
 *		-1 - skip to next token
 */
static int
getarg(
	char *str,
	int code,
	arg_v *argp
	)
{
	int isneg;
	char *cp, *np;
	static const char *digits = "0123456789";

	switch (code & ~OPT) {
	    case NTP_STR:
		argp->string = str;
		break;
	    case NTP_ADD:
		if (!strcmp("-6", str)) {
			ai_fam_templ = AF_INET6;
			return -1;
		} else if (!strcmp("-4", str)) {
			ai_fam_templ = AF_INET;
			return -1;
		}
		if (!getnetnum(str, &(argp->netnum), (char *)0, 0)) {
			return 0;
		}
		break;
	    case NTP_INT:
	    case NTP_UINT:
		isneg = 0;
		np = str;
		if (*np == '-') {
			np++;
			isneg = 1;
		}

		argp->uval = 0;
		do {
			cp = strchr(digits, *np);
			if (cp == NULL) {
				(void) fprintf(stderr,
					       "***Illegal integer value %s\n", str);
				return 0;
			}
			argp->uval *= 10;
			argp->uval += (cp - digits);
		} while (*(++np) != '\0');

		if (isneg) {
			if ((code & ~OPT) == NTP_UINT) {
				(void) fprintf(stderr,
					       "***Value %s should be unsigned\n", str);
				return 0;
			}
			argp->ival = -argp->ival;
		}
		break;
	    case IP_VERSION:
		if (!strcmp("-6", str))
			argp->ival = 6 ;
		else if (!strcmp("-4", str))
			argp->ival = 4 ;
		else {
			(void) fprintf(stderr,
			    "***Version must be either 4 or 6\n");
			return 0;
		}
		break;
	}

	return 1;
}


/*
 * getnetnum - given a host name, return its net number
 *	       and (optional) full name
 */
static int
getnetnum(
	const char *hname,
	struct sockaddr_storage *num,
	char *fullhost,
	int af
	)
{
	int sockaddr_len;
	struct addrinfo hints, *ai = NULL;

	sockaddr_len = (af == AF_INET)
			   ? sizeof(struct sockaddr_in)
			   : sizeof(struct sockaddr_in6);
	memset((char *)&hints, 0, sizeof(struct addrinfo));
	hints.ai_flags = AI_CANONNAME;
#ifdef AI_ADDRCONFIG
	hints.ai_flags |= AI_ADDRCONFIG;
#endif
	
	/* decodenetnum only works with addresses */
	if (decodenetnum(hname, num)) {
		if (fullhost != 0) {
			getnameinfo((struct sockaddr *)num, sockaddr_len, 
				    fullhost, sizeof(fullhost), NULL, 0, 
				    NI_NUMERICHOST); 
		}
		return 1;
	} else if (getaddrinfo(hname, "ntp", &hints, &ai) == 0) {
		memmove((char *)num, ai->ai_addr, ai->ai_addrlen);
		if (fullhost != 0)
			(void) strcpy(fullhost, ai->ai_canonname);
		return 1;
	} else {
		(void) fprintf(stderr, "***Can't find host %s\n", hname);
		return 0;
	}
	/*NOTREACHED*/
}

/*
 * nntohost - convert network number to host name.  This routine enforces
 *	       the showhostnames setting.
 */
char *
nntohost(
	struct sockaddr_storage *netnum
	)
{
	if (!showhostnames)
	    return stoa(netnum);

	if ((netnum->ss_family == AF_INET) && ISREFCLOCKADR(netnum))
		return refnumtoa(netnum);
	return socktohost(netnum);
}


/*
 * Finally, the built in command handlers
 */

/*
 * help - tell about commands, or details of a particular command
 */
static void
help(
	struct parse *pcmd,
	FILE *fp
	)
{
	struct xcmd *xcp;
	char *cmd;
	const char *list[100];
	int word, words;     
        int row, rows;
	int col, cols;

	if (pcmd->nargs == 0) {
		words = 0;
		for (xcp = builtins; xcp->keyword != 0; xcp++) {
			if (*(xcp->keyword) != '?')
			    list[words++] = xcp->keyword;
		}
                for (xcp = opcmds; xcp->keyword != 0; xcp++)
		    list[words++] = xcp->keyword;

		qsort(
#ifdef QSORT_USES_VOID_P
		    (void *)
#else
		    (char *)
#endif
			(list), (size_t)(words), sizeof(char *), helpsort);
		col = 0;
		for (word = 0; word < words; word++) {
			int length = strlen(list[word]);
			if (col < length) {
			    col = length;
                        }
		}

		cols = SCREENWIDTH / ++col;
                rows = (words + cols - 1) / cols;

		(void) fprintf(fp, "ntpdc commands:\n");

		for (row = 0; row < rows; row++) {
                        for (word = row; word < words; word += rows) {
				(void) fprintf(fp, "%-*.*s", col, col-1, list[word]);
                        }
			(void) fprintf(fp, "\n");
		}
	} else {
		cmd = pcmd->argval[0].string;
		words = findcmd(cmd, builtins, opcmds, &xcp);
		if (words == 0) {
			(void) fprintf(stderr,
				       "Command `%s' is unknown\n", cmd);
			return;
		} else if (words >= 2) {
			(void) fprintf(stderr,
				       "Command `%s' is ambiguous\n", cmd);
			return;
		}
		(void) fprintf(fp, "function: %s\n", xcp->comment);
		printusage(xcp, fp);
	}
}


/*
 * helpsort - do hostname qsort comparisons
 */
#ifdef QSORT_USES_VOID_P
static int
helpsort(
	const void *t1,
	const void *t2
	)
{
	char const * const * name1 = (char const * const *)t1;
	char const * const * name2 = (char const * const *)t2;

	return strcmp(*name1, *name2);
}
#else
static int
helpsort(
	char **name1,
	char **name2
	)
{
	return strcmp(*name1, *name2);
}
#endif


/*
 * printusage - print usage information for a command
 */
static void
printusage(
	struct xcmd *xcp,
	FILE *fp
	)
{
	int i, opt46;

	opt46 = 0;
	(void) fprintf(fp, "usage: %s", xcp->keyword);
	for (i = 0; i < MAXARGS && xcp->arg[i] != NO; i++) {
		if (opt46 == 0 && (xcp->arg[i] & ~OPT) == NTP_ADD) {
			(void) fprintf(fp, " [ -4|-6 ]");
			opt46 = 1;
		}
		if (xcp->arg[i] & OPT)
		    (void) fprintf(fp, " [ %s ]", xcp->desc[i]);
		else
		    (void) fprintf(fp, " %s", xcp->desc[i]);
	}
	(void) fprintf(fp, "\n");
}


/*
 * timeout - set time out time
 */
static void
timeout(
	struct parse *pcmd,
	FILE *fp
	)
{
	int val;

	if (pcmd->nargs == 0) {
		val = tvout.tv_sec * 1000 + tvout.tv_usec / 1000;
		(void) fprintf(fp, "primary timeout %d ms\n", val);
	} else {
		tvout.tv_sec = pcmd->argval[0].uval / 1000;
		tvout.tv_usec = (pcmd->argval[0].uval - (tvout.tv_sec * 1000))
			* 1000;
	}
}


/*
 * my_delay - set delay for auth requests
 */
static void
my_delay(
	struct parse *pcmd,
	FILE *fp
	)
{
	int isneg;
	u_long val;

	if (pcmd->nargs == 0) {
		val = delay_time.l_ui * 1000 + delay_time.l_uf / 4294967;
		(void) fprintf(fp, "delay %lu ms\n", val);
	} else {
		if (pcmd->argval[0].ival < 0) {
			isneg = 1;
			val = (u_long)(-pcmd->argval[0].ival);
		} else {
			isneg = 0;
			val = (u_long)pcmd->argval[0].ival;
		}

		delay_time.l_ui = val / 1000;
		val %= 1000;
		delay_time.l_uf = val * 4294967;	/* 2**32/1000 */

		if (isneg)
		    L_NEG(&delay_time);
	}
}


/*
 * host - set the host we are dealing with.
 */
static void
host(
	struct parse *pcmd,
	FILE *fp
	)
{
	int i;

	if (pcmd->nargs == 0) {
		if (havehost)
		    (void) fprintf(fp, "current host is %s\n", currenthost);
		else
		    (void) fprintf(fp, "no current host\n");
		return;
	}

	i = 0;
	if (pcmd->nargs == 2) {
		if (!strcmp("-4", pcmd->argval[i].string))
			ai_fam_templ = AF_INET;
		else if (!strcmp("-6", pcmd->argval[i].string))
			ai_fam_templ = AF_INET6;
		else {
			if (havehost)
				(void) fprintf(fp,
				    "current host remains %s\n", currenthost);
			else
				(void) fprintf(fp, "still no current host\n");
			return;
		}
		i = 1;
	}
	if (openhost(pcmd->argval[i].string)) {
		(void) fprintf(fp, "current host set to %s\n", currenthost);
	} else {
		if (havehost)
		    (void) fprintf(fp,
				   "current host remains %s\n", currenthost);
		else
		    (void) fprintf(fp, "still no current host\n");
	}
}


/*
 * keyid - get a keyid to use for authenticating requests
 */
static void
keyid(
	struct parse *pcmd,
	FILE *fp
	)
{
	if (pcmd->nargs == 0) {
		if (info_auth_keyid == 0)
		    (void) fprintf(fp, "no keyid defined\n");
		else
		    (void) fprintf(fp, "keyid is %lu\n", (u_long)info_auth_keyid);
	} else {
		info_auth_keyid = pcmd->argval[0].uval;
	}
}


/*
 * keytype - get type of key to use for authenticating requests
 */
static void
keytype(
	struct parse *pcmd,
	FILE *fp
	)
{
	if (pcmd->nargs == 0)
	    fprintf(fp, "keytype is %s\n",
		    (info_auth_keytype == KEY_TYPE_MD5) ? "MD5" : "???");
	else
	    switch (*(pcmd->argval[0].string)) {
		case 'm':
		case 'M':
		    info_auth_keytype = KEY_TYPE_MD5;
		    break;

		default:
		    fprintf(fp, "keytype must be 'md5'\n");
	    }
}



/*
 * passwd - get an authentication key
 */
/*ARGSUSED*/
static void
passwd(
	struct parse *pcmd,
	FILE *fp
	)
{
	char *pass;

	if (info_auth_keyid == 0) {
		info_auth_keyid = getkeyid("Keyid: ");
		if (info_auth_keyid == 0) {
			(void)fprintf(fp, "Keyid must be defined\n");
			return;
		}
	}
	if (!interactive) {
		authusekey(info_auth_keyid, info_auth_keytype,
			   (u_char *)pcmd->argval[0].string);
		authtrust(info_auth_keyid, 1);
	} else {
		pass = getpass("MD5 Password: ");
		if (*pass == '\0')
		    (void) fprintf(fp, "Password unchanged\n");
		else {
		    authusekey(info_auth_keyid, info_auth_keytype,
			       (u_char *)pass);
		    authtrust(info_auth_keyid, 1);
		}
	}
}


/*
 * hostnames - set the showhostnames flag
 */
static void
hostnames(
	struct parse *pcmd,
	FILE *fp
	)
{
	if (pcmd->nargs == 0) {
		if (showhostnames)
		    (void) fprintf(fp, "hostnames being shown\n");
		else
		    (void) fprintf(fp, "hostnames not being shown\n");
	} else {
		if (STREQ(pcmd->argval[0].string, "yes"))
		    showhostnames = 1;
		else if (STREQ(pcmd->argval[0].string, "no"))
		    showhostnames = 0;
		else
		    (void)fprintf(stderr, "What?\n");
	}
}


/*
 * setdebug - set/change debugging level
 */
static void
setdebug(
	struct parse *pcmd,
	FILE *fp
	)
{
	if (pcmd->nargs == 0) {
		(void) fprintf(fp, "debug level is %d\n", debug);
		return;
	} else if (STREQ(pcmd->argval[0].string, "no")) {
		debug = 0;
	} else if (STREQ(pcmd->argval[0].string, "more")) {
		debug++;
	} else if (STREQ(pcmd->argval[0].string, "less")) {
		debug--;
	} else {
		(void) fprintf(fp, "What?\n");
		return;
	}
	(void) fprintf(fp, "debug level set to %d\n", debug);
}


/*
 * quit - stop this nonsense
 */
/*ARGSUSED*/
static void
quit(
	struct parse *pcmd,
	FILE *fp
	)
{
	if (havehost)
	    closesocket(sockfd);
	exit(0);
}


/*
 * version - print the current version number
 */
/*ARGSUSED*/
static void
version(
	struct parse *pcmd,
	FILE *fp
	)
{

	(void) fprintf(fp, "%s\n", Version);
	return;
}


/*
 * warning - print a warning message
 */
static void
warning(
	const char *fmt,
	const char *st1,
	const char *st2
	)
{
	(void) fprintf(stderr, "%s: ", progname);
	(void) fprintf(stderr, fmt, st1, st2);
	(void) fprintf(stderr, ": ");
	perror("");
}


/*
 * error - print a message and exit
 */
static void
error(
	const char *fmt,
	const char *st1,
	const char *st2
	)
{
	warning(fmt, st1, st2);
	exit(1);
}

/*
 * getkeyid - prompt the user for a keyid to use
 */
static u_long
getkeyid(
	const char *keyprompt
	)
{
	register char *p;
	register int c;
	FILE *fi;
	char pbuf[20];

#ifndef SYS_WINNT
	if ((fi = fdopen(open("/dev/tty", 2), "r")) == NULL)
#else
	    if ((fi = _fdopen((int)GetStdHandle(STD_INPUT_HANDLE), "r")) == NULL)
#endif /* SYS_WINNT */
		fi = stdin;
	    else
		setbuf(fi, (char *)NULL);
	fprintf(stderr, "%s", keyprompt); fflush(stderr);
	for (p=pbuf; (c = getc(fi))!='\n' && c!=EOF;) {
		if (p < &pbuf[18])
		    *p++ = (char) c;
	}
	*p = '\0';
	if (fi != stdin)
	    fclose(fi);
	return (u_int32)atoi(pbuf);
}