From 3da4cc02e3a32b2b7567ebba2bad2b685b77c052 Mon Sep 17 00:00:00 2001
From: Michael Tremer <michael.tremer@ipfire.org>
Date: Wed, 7 May 2014 12:16:57 +0200
Subject: [PATCH] dnsmasq: Update ISC dhcpd reader patch.

---
 ...-support-to-read-ISC-DHCP-lease-file.patch | 99 +++++++++----------
 1 file changed, 49 insertions(+), 50 deletions(-)

diff --git a/src/patches/dnsmasq-2.70-Add-support-to-read-ISC-DHCP-lease-file.patch b/src/patches/dnsmasq-2.70-Add-support-to-read-ISC-DHCP-lease-file.patch
index 88eb6a217e..3194e1f229 100644
--- a/src/patches/dnsmasq-2.70-Add-support-to-read-ISC-DHCP-lease-file.patch
+++ b/src/patches/dnsmasq-2.70-Add-support-to-read-ISC-DHCP-lease-file.patch
@@ -1,18 +1,3 @@
-From b3c0d11d8bcf810b8f50f695ea36c8183fa4791a Mon Sep 17 00:00:00 2001
-From: Michael Tremer <michael.tremer@ipfire.org>
-Date: Mon, 28 Apr 2014 00:51:13 +0200
-Subject: [PATCH] Add support to read ISC DHCP lease file.
-
----
- Makefile      |   2 +-
- src/cache.c   |  13 +++-
- src/dnsmasq.c |   5 ++
- src/dnsmasq.h |   5 ++
- src/isc.c     | 234 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
- src/option.c  |   2 +-
- 6 files changed, 256 insertions(+), 5 deletions(-)
- create mode 100644 src/isc.c
-
 diff --git a/Makefile b/Makefile
 index 292c8bd..5e0cdbe 100644
 --- a/Makefile
@@ -110,10 +95,10 @@ index 3032546..a40b2a9 100644
 +#endif
 diff --git a/src/isc.c b/src/isc.c
 new file mode 100644
-index 0000000..565e4e2
+index 0000000..5106442
 --- /dev/null
 +++ b/src/isc.c
-@@ -0,0 +1,234 @@
+@@ -0,0 +1,251 @@
 +/* dnsmasq is Copyright (c) 2014 John Volpe, Simon Kelley and
 +     Michael Tremer
 +
@@ -148,11 +133,14 @@ index 0000000..565e4e2
 +	struct isc_dhcp_lease* next;
 +};
 +
-+static struct isc_dhcp_lease* dhcp_lease_new() {
++static struct isc_dhcp_lease* dhcp_lease_new(const char* hostname) {
 +	struct isc_dhcp_lease* lease = whine_malloc(sizeof(*lease));
 +
-+	lease->name = NULL;
-+	lease->fqdn = NULL;
++	lease->name = strdup(hostname);
++	if (daemon->domain_suffix) {
++		asprintf(&lease->fqdn, "%s.%s", hostname, daemon->domain_suffix);
++	}
++	lease->expires = 0;
 +	lease->next = NULL;
 +
 +	return lease;
@@ -193,34 +181,42 @@ index 0000000..565e4e2
 +	return count ? 1 : 0;
 +}
 +
++static long get_utc_offset() {
++	time_t t = time(NULL);
++	struct tm* time_struct = localtime(&t);
++
++	return time_struct->tm_gmtoff;
++}
++
 +static time_t parse_lease_time(const char* token_date, const char* token_time) {
 +	time_t time = (time_t)(-1);
 +	struct tm lease_time;
 +
-+	static const int months[11] = {31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334};
-+
 +	if (sscanf(token_date, "%d/%d/%d", &lease_time.tm_year, &lease_time.tm_mon, &lease_time.tm_mday) == 3) {
++		lease_time.tm_year -= 1900;
++		lease_time.tm_mon -= 1;
++
 +		if (sscanf(token_time, "%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. */
-+			time = ((((((365 * (lease_time.tm_year - 1970) +
-+				(lease_time.tm_year - 1969) / 4 +
-+				(lease_time.tm_mon > 1 ? months[lease_time.tm_mon - 2] : 0) +
-+				(lease_time.tm_mon > 2 && !((lease_time.tm_year - 1972) & 3 )) +
-+				(lease_time.tm_mday - 1)) * 24) +
-+				 lease_time.tm_hour) * 60) +
-+				 lease_time.tm_mon) * 60) +
-+				 lease_time.tm_sec;
++			time = mktime(&lease_time) + get_utc_offset();
 +		}
 +	}
 +
 +	return time;
 +}
 +
++static struct isc_dhcp_lease* find_lease(const char* hostname, struct isc_dhcp_lease* leases) {
++	struct isc_dhcp_lease* lease = leases;
++
++	while (lease) {
++		if (strcmp(hostname, lease->name) == 0) {
++			return lease;
++		}
++		lease = lease->next;
++	}
++
++	return NULL;
++}
++
 +static off_t lease_file_size = (off_t)0;
 +static ino_t lease_file_inode = (ino_t)0;
 +
@@ -306,20 +302,26 @@ index 0000000..565e4e2
 +						*dot = 0;
 +					}
 +
-+					struct isc_dhcp_lease* lease = dhcp_lease_new();
-+					lease->name = strdup(hostname);
-+					lease->addr = host_address;
-+					lease->expires = time_ends;
-+					lease->next = NULL;
++					// Search for an existing lease in the list
++					// with the given host name and update the data
++					// if needed.
++					struct isc_dhcp_lease* lease = find_lease(hostname, leases);
 +
-+					if (daemon->domain_suffix) {
-+						asprintf(&lease->fqdn, "%s.%s", hostname, daemon->domain_suffix);
-+					}
++					// If no lease already exists, we create a new one
++					// and append it to the list.
++					if (!lease) {
++						lease = dhcp_lease_new(hostname);
 +
-+					if (!leases)
++						lease->next = leases;
 +						leases = lease;
-+					else
-+						leases->next = lease;
++					}
++
++					// Only update more recent leases.
++					if (lease->expires > time_ends)
++						continue;
++
++					lease->addr = host_address;
++					lease->expires = time_ends;
 +				}
 +			}
 +		}
@@ -361,6 +363,3 @@ index daa728f..d16c982 100644
      case 'l':  /* --dhcp-leasefile */
        daemon->lease_file = opt_string_alloc(arg);
        break;
--- 
-1.9.0
-
-- 
2.39.5