mirror of
https://github.com/pi-hole/dnsmasq.git
synced 2025-12-19 18:28:25 +00:00
import of dnsmasq-2.6.tar.gz
This commit is contained in:
Simon Kelley
249
src/isc.c
Normal file
249
src/isc.c
Normal file
@@ -0,0 +1,249 @@
|
||||
/* dnsmasq is Copyright (c) 2000 - 2004 by Simon Kelley
|
||||
|
||||
This program is free software; you can redistribute it and/or modify
|
||||
it under the terms of the GNU General Public License as published by
|
||||
the Free Software Foundation; version 2 dated June, 1991.
|
||||
|
||||
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.
|
||||
*/
|
||||
|
||||
|
||||
/* Code in this file is based on contributions by John Volpe. */
|
||||
|
||||
#include "dnsmasq.h"
|
||||
|
||||
#ifdef HAVE_ISC_READER
|
||||
|
||||
struct isc_lease {
|
||||
char *name, *fqdn;
|
||||
time_t expires;
|
||||
struct in_addr addr;
|
||||
struct isc_lease *next;
|
||||
};
|
||||
|
||||
static struct isc_lease *leases = NULL;
|
||||
static off_t lease_file_size = (off_t)0;
|
||||
static ino_t lease_file_inode = (ino_t)0;
|
||||
static int logged_lease = 0;
|
||||
|
||||
static int next_token (char *token, int buffsize, FILE * fp)
|
||||
{
|
||||
int c, count = 0;
|
||||
char *cp = token;
|
||||
|
||||
while((c = getc(fp)) != EOF)
|
||||
{
|
||||
if (c == '#')
|
||||
do { c = getc(fp); } while (c != '\n' && c != EOF);
|
||||
|
||||
if (c == ' ' || c == '\t' || c == '\n' || c == ';')
|
||||
{
|
||||
if (count)
|
||||
break;
|
||||
}
|
||||
else if ((c != '"') && (count<buffsize-1))
|
||||
{
|
||||
*cp++ = c;
|
||||
count++;
|
||||
}
|
||||
}
|
||||
|
||||
*cp = 0;
|
||||
return count ? 1 : 0;
|
||||
}
|
||||
|
||||
void load_dhcp(char *file, char *suffix, time_t now, char *hostname)
|
||||
{
|
||||
char token[MAXTOK], *dot;
|
||||
struct in_addr host_address;
|
||||
time_t ttd, tts;
|
||||
FILE *fp;
|
||||
struct isc_lease *lease, *tmp, **up;
|
||||
struct stat statbuf;
|
||||
|
||||
if (stat(file, &statbuf) == -1)
|
||||
{
|
||||
if (!logged_lease)
|
||||
syslog(LOG_WARNING, "failed to access %s: %m", file);
|
||||
logged_lease = 1;
|
||||
return;
|
||||
}
|
||||
|
||||
logged_lease = 0;
|
||||
|
||||
if ((statbuf.st_size <= lease_file_size) &&
|
||||
(statbuf.st_ino == lease_file_inode))
|
||||
return;
|
||||
|
||||
lease_file_size = statbuf.st_size;
|
||||
lease_file_inode = statbuf.st_ino;
|
||||
|
||||
if (!(fp = fopen (file, "r")))
|
||||
{
|
||||
syslog (LOG_ERR, "failed to load %s: %m", file);
|
||||
return;
|
||||
}
|
||||
|
||||
syslog (LOG_INFO, "reading %s", file);
|
||||
|
||||
while ((next_token(token, MAXTOK, fp)))
|
||||
{
|
||||
if (strcmp(token, "lease") == 0)
|
||||
{
|
||||
hostname[0] = '\0';
|
||||
ttd = tts = (time_t)(-1);
|
||||
if (next_token(token, MAXTOK, fp) &&
|
||||
(host_address.s_addr = inet_addr(token)) != (in_addr_t) -1)
|
||||
{
|
||||
if (next_token(token, MAXTOK, fp) && *token == '{')
|
||||
{
|
||||
while (next_token(token, MAXTOK, fp) && *token != '}')
|
||||
{
|
||||
if ((strcmp(token, "client-hostname") == 0) ||
|
||||
(strcmp(token, "hostname") == 0))
|
||||
{
|
||||
if (next_token(hostname, MAXDNAME, fp))
|
||||
if (!canonicalise(hostname))
|
||||
{
|
||||
*hostname = 0;
|
||||
syslog(LOG_ERR, "bad name in %s", file);
|
||||
}
|
||||
}
|
||||
else if ((strcmp(token, "ends") == 0) ||
|
||||
(strcmp(token, "starts") == 0))
|
||||
{
|
||||
struct tm lease_time;
|
||||
int is_ends = (strcmp(token, "ends") == 0);
|
||||
if (next_token(token, MAXTOK, fp) && /* skip weekday */
|
||||
next_token(token, MAXTOK, fp) && /* Get date from lease file */
|
||||
sscanf (token, "%d/%d/%d",
|
||||
&lease_time.tm_year,
|
||||
&lease_time.tm_mon,
|
||||
&lease_time.tm_mday) == 3 &&
|
||||
next_token(token, MAXTOK, fp) &&
|
||||
sscanf (token, "%d:%d:%d:",
|
||||
&lease_time.tm_hour,
|
||||
&lease_time.tm_min,
|
||||
&lease_time.tm_sec) == 3)
|
||||
{
|
||||
/* There doesn't seem to be a universally available library function
|
||||
which converts broken-down _GMT_ time to seconds-in-epoch.
|
||||
The following was borrowed from ISC dhcpd sources, where
|
||||
it is noted that it might not be entirely accurate for odd seconds.
|
||||
Since we're trying to get the same answer as dhcpd, that's just
|
||||
fine here. */
|
||||
static int months [11] = { 31, 59, 90, 120, 151, 181,
|
||||
212, 243, 273, 304, 334 };
|
||||
time_t time = ((((((365 * (lease_time.tm_year - 1970) + /* Days in years since '70 */
|
||||
(lease_time.tm_year - 1969) / 4 + /* Leap days since '70 */
|
||||
(lease_time.tm_mon > 1 /* Days in months this year */
|
||||
? months [lease_time.tm_mon - 2]
|
||||
: 0) +
|
||||
(lease_time.tm_mon > 2 && /* Leap day this year */
|
||||
!((lease_time.tm_year - 1972) & 3)) +
|
||||
lease_time.tm_mday - 1) * 24) + /* Day of month */
|
||||
lease_time.tm_hour) * 60) +
|
||||
lease_time.tm_min) * 60) + lease_time.tm_sec;
|
||||
if (is_ends)
|
||||
ttd = time;
|
||||
else
|
||||
tts = time; }
|
||||
}
|
||||
}
|
||||
|
||||
/* missing info? */
|
||||
if (!*hostname)
|
||||
continue;
|
||||
if (ttd == (time_t)(-1))
|
||||
continue;
|
||||
|
||||
/* We use 0 as infinite in ttd */
|
||||
if ((tts != -1) && (ttd == tts - 1))
|
||||
ttd = (time_t)0;
|
||||
else if (difftime(now, ttd) > 0)
|
||||
continue;
|
||||
|
||||
if ((dot = strchr(hostname, '.')))
|
||||
{
|
||||
if (!suffix || hostname_isequal(dot+1, suffix))
|
||||
{
|
||||
syslog(LOG_WARNING,
|
||||
"Ignoring DHCP lease for %s because it has an illegal domain part",
|
||||
hostname);
|
||||
continue;
|
||||
}
|
||||
*dot = 0;
|
||||
}
|
||||
|
||||
for (lease = leases; lease; lease = lease->next)
|
||||
if (hostname_isequal(lease->name, hostname))
|
||||
{
|
||||
lease->expires = ttd;
|
||||
lease->addr = host_address;
|
||||
break;
|
||||
}
|
||||
|
||||
if (!lease && (lease = malloc(sizeof(struct isc_lease))))
|
||||
{
|
||||
lease->expires = ttd;
|
||||
lease->addr = host_address;
|
||||
lease->fqdn = NULL;
|
||||
lease->next = leases;
|
||||
if (!(lease->name = malloc(strlen(hostname)+1)))
|
||||
free(lease);
|
||||
else
|
||||
{
|
||||
leases = lease;
|
||||
strcpy(lease->name, hostname);
|
||||
if (suffix && (lease->fqdn = malloc(strlen(hostname) + strlen(suffix) + 2)))
|
||||
{
|
||||
strcpy(lease->fqdn, hostname);
|
||||
strcat(lease->fqdn, ".");
|
||||
strcat(lease->fqdn, suffix);
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
fclose(fp);
|
||||
|
||||
/* prune expired leases */
|
||||
for (lease = leases, up = &leases; lease; lease = tmp)
|
||||
{
|
||||
tmp = lease->next;
|
||||
if (lease->expires != (time_t)0 && difftime(now, lease->expires) > 0)
|
||||
{
|
||||
*up = lease->next; /* unlink */
|
||||
free(lease->name);
|
||||
if (lease->fqdn)
|
||||
free(lease->fqdn);
|
||||
free(lease);
|
||||
}
|
||||
else
|
||||
up = &lease->next;
|
||||
}
|
||||
|
||||
|
||||
/* remove all existing DHCP cache entries */
|
||||
cache_unhash_dhcp();
|
||||
|
||||
for (lease = leases; lease; lease = lease->next)
|
||||
{
|
||||
if (lease->fqdn)
|
||||
{
|
||||
cache_add_dhcp_entry(lease->fqdn, &lease->addr, lease->expires, F_REVERSE);
|
||||
cache_add_dhcp_entry(lease->name, &lease->addr, lease->expires, 0);
|
||||
}
|
||||
else
|
||||
cache_add_dhcp_entry(lease->name, &lease->addr, lease->expires, F_REVERSE);
|
||||
}
|
||||
}
|
||||
|
||||
#endif
|
||||
|
||||
Reference in New Issue
Block a user