Files
chrony/cmdparse.c
Miroslav Lichvar 9b183fe98f sources: add option to limit selection of unreachable sources
Add maxunreach option to NTP sources and refclocks to specify the
maximum number of polls that the source can stay selected for
synchronization when it is unreachable (i.e. no valid sample was
received in the last 8 polls).

It is an additional requirement to having at least one sample more
recent than the oldest sample of reachable sources.

The default value is 100000. Setting the option to 0 disables selection
of unreachable sources, which matches RFC 5905.
2025-08-07 10:18:31 +02:00

458 lines
13 KiB
C

/*
chronyd/chronyc - Programs for keeping computer clocks accurate.
**********************************************************************
* Copyright (C) Richard P. Curnow 1997-2003
* Copyright (C) Miroslav Lichvar 2013-2014, 2016, 2021
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
**********************************************************************
=======================================================================
Module for parsing various forms of directive and command lines that
are common to the configuration file and to the command client.
*/
#include "config.h"
#include "sysincl.h"
#include "cmdparse.h"
#include "memory.h"
#include "nameserv.h"
#include "ntp.h"
#include "util.h"
/* ================================================== */
#define SSCANF_IN_RANGE(s, f, x, n, min, max) \
(sscanf((s), (f), (x), (n)) == 1 && *(x) >= (min) && *(x) <= (max))
/* ================================================== */
CPS_Status
CPS_ParseNTPSourceAdd(char *line, CPS_NTP_Source *src)
{
char *hostname, *cmd;
uint32_t ef_type;
int n, sel_option;
src->family = IPADDR_UNSPEC;
src->port = SRC_DEFAULT_PORT;
src->params.minpoll = SRC_DEFAULT_MINPOLL;
src->params.maxpoll = SRC_DEFAULT_MAXPOLL;
src->params.connectivity = SRC_ONLINE;
src->params.auto_offline = 0;
src->params.presend_minpoll = SRC_DEFAULT_PRESEND_MINPOLL;
src->params.burst = 0;
src->params.iburst = 0;
src->params.min_stratum = SRC_DEFAULT_MINSTRATUM;
src->params.poll_target = SRC_DEFAULT_POLLTARGET;
src->params.version = 0;
src->params.max_sources = SRC_DEFAULT_MAXSOURCES;
src->params.min_samples = SRC_DEFAULT_MINSAMPLES;
src->params.max_samples = SRC_DEFAULT_MAXSAMPLES;
src->params.max_unreach = SRC_DEFAULT_MAXUNREACH;
src->params.filter_length = 0;
src->params.interleaved = 0;
src->params.sel_options = 0;
src->params.nts = 0;
src->params.nts_port = SRC_DEFAULT_NTSPORT;
src->params.copy = 0;
src->params.ext_fields = 0;
src->params.authkey = INACTIVE_AUTHKEY;
src->params.cert_set = SRC_DEFAULT_CERTSET;
src->params.max_delay = SRC_DEFAULT_MAXDELAY;
src->params.max_delay_ratio = SRC_DEFAULT_MAXDELAYRATIO;
src->params.max_delay_dev_ratio = SRC_DEFAULT_MAXDELAYDEVRATIO;
src->params.max_delay_quant = 0.0;
src->params.min_delay = 0.0;
src->params.asymmetry = SRC_DEFAULT_ASYMMETRY;
src->params.offset = 0.0;
hostname = line;
line = CPS_SplitWord(line);
if (!*hostname)
return CPS_MissingArgument;
src->name = hostname;
/* Parse options */
for (; *line; line += n) {
cmd = line;
line = CPS_SplitWord(line);
n = 0;
if (!strcasecmp(cmd, "auto_offline")) {
src->params.auto_offline = 1;
} else if (!strcasecmp(cmd, "burst")) {
src->params.burst = 1;
} else if (!strcasecmp(cmd, "copy")) {
src->params.copy = 1;
} else if (!strcasecmp(cmd, "iburst")) {
src->params.iburst = 1;
} else if (!strcasecmp(cmd, "offline")) {
src->params.connectivity = SRC_OFFLINE;
} else if (!strcasecmp(cmd, "certset")) {
if (sscanf(line, "%"SCNu32"%n", &src->params.cert_set, &n) != 1)
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "key")) {
if (sscanf(line, "%"SCNu32"%n", &src->params.authkey, &n) != 1 ||
src->params.authkey == INACTIVE_AUTHKEY)
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "asymmetry")) {
if (sscanf(line, "%lf%n", &src->params.asymmetry, &n) != 1)
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "extfield")) {
if (sscanf(line, "%"SCNx32"%n", &ef_type, &n) != 1)
return CPS_InvalidValue;
switch (ef_type) {
case NTP_EF_EXP_MONO_ROOT:
src->params.ext_fields |= NTP_EF_FLAG_EXP_MONO_ROOT;
break;
case NTP_EF_EXP_NET_CORRECTION:
src->params.ext_fields |= NTP_EF_FLAG_EXP_NET_CORRECTION;
break;
default:
return CPS_InvalidValue;
}
} else if (!strcasecmp(cmd, "filter")) {
if (!SSCANF_IN_RANGE(line, "%d%n", &src->params.filter_length, &n, 0, INT_MAX))
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "ipv4")) {
src->family = IPADDR_INET4;
} else if (!strcasecmp(cmd, "ipv6")) {
src->family = IPADDR_INET6;
} else if (!strcasecmp(cmd, "maxdelay")) {
if (sscanf(line, "%lf%n", &src->params.max_delay, &n) != 1)
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "maxdelayratio")) {
if (sscanf(line, "%lf%n", &src->params.max_delay_ratio, &n) != 1)
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "maxdelaydevratio")) {
if (sscanf(line, "%lf%n", &src->params.max_delay_dev_ratio, &n) != 1)
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "maxdelayquant")) {
if (sscanf(line, "%lf%n", &src->params.max_delay_quant, &n) != 1)
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "maxpoll")) {
if (!SSCANF_IN_RANGE(line, "%d%n", &src->params.maxpoll, &n, -32, 32))
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "maxsamples")) {
if (!SSCANF_IN_RANGE(line, "%d%n", &src->params.max_samples, &n, 0, INT_MAX))
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "maxsources")) {
if (!SSCANF_IN_RANGE(line, "%d%n", &src->params.max_sources, &n, 1, INT_MAX))
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "maxunreach")) {
if (!SSCANF_IN_RANGE(line, "%d%n", &src->params.max_unreach, &n, 0, INT_MAX))
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "mindelay")) {
if (sscanf(line, "%lf%n", &src->params.min_delay, &n) != 1)
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "minpoll")) {
if (sscanf(line, "%d%n", &src->params.minpoll, &n) != 1)
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "minsamples")) {
if (!SSCANF_IN_RANGE(line, "%d%n", &src->params.min_samples, &n, 0, INT_MAX))
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "minstratum")) {
if (!SSCANF_IN_RANGE(line, "%d%n", &src->params.min_stratum, &n, 0, NTP_MAX_STRATUM))
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "nts")) {
src->params.nts = 1;
} else if (!strcasecmp(cmd, "ntsport")) {
if (!SSCANF_IN_RANGE(line, "%d%n", &src->params.nts_port, &n, 0, 65535))
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "offset")) {
if (sscanf(line, "%lf%n", &src->params.offset, &n) != 1)
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "port")) {
if (!SSCANF_IN_RANGE(line, "%d%n", &src->port, &n, 0, 65535))
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "polltarget")) {
if (!SSCANF_IN_RANGE(line, "%d%n", &src->params.poll_target, &n, 1, INT_MAX))
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "presend")) {
if (!SSCANF_IN_RANGE(line, "%d%n", &src->params.presend_minpoll, &n, -32, 32))
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "version")) {
if (!SSCANF_IN_RANGE(line, "%d%n", &src->params.version, &n, 1, NTP_VERSION))
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "xleave")) {
src->params.interleaved = 1;
} else if ((sel_option = CPS_GetSelectOption(cmd)) != 0) {
src->params.sel_options |= sel_option;
} else {
return CPS_InvalidOption;
}
}
return CPS_Success;
}
/* ================================================== */
int
CPS_GetSelectOption(char *option)
{
if (!strcasecmp(option, "noselect")) {
return SRC_SELECT_NOSELECT;
} else if (!strcasecmp(option, "prefer")) {
return SRC_SELECT_PREFER;
} else if (!strcasecmp(option, "require")) {
return SRC_SELECT_REQUIRE;
} else if (!strcasecmp(option, "trust")) {
return SRC_SELECT_TRUST;
}
return 0;
}
/* ================================================== */
int
CPS_ParseAllowDeny(char *line, int *all, IPAddr *ip, int *subnet_bits)
{
char *p, *net, *slash;
uint32_t a, b, c;
int bits, len, n;
p = CPS_SplitWord(line);
if (strcmp(line, "all") == 0) {
*all = 1;
net = p;
p = CPS_SplitWord(p);
} else {
*all = 0;
net = line;
}
/* Make sure there are no other arguments */
if (*p)
return 0;
/* No specified address or network means all IPv4 and IPv6 addresses */
if (!*net) {
ip->family = IPADDR_UNSPEC;
*subnet_bits = 0;
return 1;
}
slash = strchr(net, '/');
if (slash) {
if (sscanf(slash + 1, "%d%n", &bits, &len) != 1 || slash[len + 1] || bits < 0)
return 0;
*slash = '\0';
} else {
bits = -1;
}
if (UTI_StringToIP(net, ip)) {
if (bits >= 0)
*subnet_bits = bits;
else
*subnet_bits = ip->family == IPADDR_INET6 ? 128 : 32;
return 1;
}
/* Check for a shortened IPv4 network notation using only 1, 2, or 3 decimal
numbers. This is different than the numbers-and-dots notation accepted
by inet_aton()! */
a = b = c = 0;
n = sscanf(net, "%"PRIu32"%n.%"PRIu32"%n.%"PRIu32"%n", &a, &len, &b, &len, &c, &len);
if (n > 0 && !net[len]) {
if (a > 255 || b > 255 || c > 255)
return 0;
ip->family = IPADDR_INET4;
ip->addr.in4 = (a << 24) | (b << 16) | (c << 8);
if (bits >= 0)
*subnet_bits = bits;
else
*subnet_bits = n * 8;
return 1;
}
/* The last possibility is a hostname */
if (bits < 0 && DNS_Name2IPAddress(net, ip, 1) == DNS_Success) {
*subnet_bits = ip->family == IPADDR_INET6 ? 128 : 32;
return 1;
}
return 0;
}
/* ================================================== */
CPS_Status
CPS_ParseLocal(char *line, int *stratum, int *orphan, double *distance, double *activate,
double *wait_synced, double *wait_unsynced)
{
int n;
char *cmd;
*stratum = 10;
*distance = 1.0;
*activate = 0.0;
*orphan = 0;
*wait_synced = 0;
*wait_unsynced = -1.0;
while (*line) {
cmd = line;
line = CPS_SplitWord(line);
if (!strcasecmp(cmd, "stratum")) {
if (!SSCANF_IN_RANGE(line, "%d%n", stratum, &n, 1, NTP_MAX_STRATUM - 1))
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "orphan")) {
*orphan = 1;
n = 0;
} else if (!strcasecmp(cmd, "distance")) {
if (sscanf(line, "%lf%n", distance, &n) != 1)
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "activate")) {
if (sscanf(line, "%lf%n", activate, &n) != 1)
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "waitsynced")) {
if (sscanf(line, "%lf%n", wait_synced, &n) != 1)
return CPS_InvalidValue;
} else if (!strcasecmp(cmd, "waitunsynced")) {
if (sscanf(line, "%lf%n", wait_unsynced, &n) != 1)
return CPS_InvalidValue;
} else {
return CPS_InvalidOption;
}
line += n;
}
if (*wait_unsynced < 0.0)
*wait_unsynced = *orphan ? 300 : 0.0;
return CPS_Success;
}
/* ================================================== */
void
CPS_NormalizeLine(char *line)
{
char *p, *q;
int space = 1, first = 1;
/* Remove white-space at beginning and replace white-spaces with space char */
for (p = q = line; *p; p++) {
if (isspace((unsigned char)*p)) {
if (!space)
*q++ = ' ';
space = 1;
continue;
}
/* Discard comment lines */
if (first && strchr("!;#%", *p))
break;
*q++ = *p;
space = first = 0;
}
/* Strip trailing space */
if (q > line && q[-1] == ' ')
q--;
*q = '\0';
}
/* ================================================== */
char *
CPS_SplitWord(char *line)
{
char *p = line, *q = line;
/* Skip white-space before the word */
while (*q && isspace((unsigned char)*q))
q++;
/* Move the word to the beginning */
while (*q && !isspace((unsigned char)*q))
*p++ = *q++;
/* Find the next word */
while (*q && isspace((unsigned char)*q))
q++;
*p = '\0';
/* Return pointer to the next word or NUL */
return q;
}
/* ================================================== */
int
CPS_ParseKey(char *line, uint32_t *id, const char **type, char **key)
{
char *s1, *s2, *s3, *s4;
s1 = line;
s2 = CPS_SplitWord(s1);
s3 = CPS_SplitWord(s2);
s4 = CPS_SplitWord(s3);
/* Require two or three words */
if (!*s2 || *s4)
return 0;
if (sscanf(s1, "%"SCNu32, id) != 1)
return 0;
if (*s3) {
*type = s2;
*key = s3;
} else {
*type = "MD5";
*key = s2;
}
return 1;
}
/* ================================================== */
int
CPS_ParseRefid(char *line, uint32_t *ref_id)
{
int i;
for (i = *ref_id = 0; line[i] && !isspace((unsigned char)line[i]); i++) {
if (i >= 4)
return 0;
*ref_id |= (uint32_t)line[i] << (24 - i * 8);
}
return i;
}