- The minimum site code value was set to 224 in 3.1.0 to track RFC3942. This

  broke a lot of legacy site local configurations.  The new code in place will
  track site local space minimum option codes and logs a warning to encourage
  updates and exploration of site local code migration problems.  Option
  codes less than 128 in site local spaces remain inaccessible.
  [ISC-Bugs #17203]
- A possible relay agent option bug was repaired where random server
  initialization state may have been used to signal the relay agent
  information options sub-option code for the 'END' of the option space.
  [ISC-Bugs #17203]

5 files changed, 93 insertions, 3 deletions

diff --git a/RELNOTES b/RELNOTES
index d4585604..f60f5fa3 100644
--- a/RELNOTES
+++ b/RELNOTES
@@ -98,6 +98,16 @@ suggested fixes to <dhcp-users@isc.org>.
   'address' parameter (the server's local address) did not resolve to an
   IPv4 address.
 
+- The minimum site code value was set to 224 in 3.1.0 to track RFC3942.  This
+  broke a lot of legacy site local configurations.  The new code in place will
+  track site local space minimum option codes and logs a warning to encourage
+  updates and exploration of site local code migration problems.  Option
+  codes less than 128 in site local spaces remain inaccessible.
+
+- A possible relay agent option bug was repaired where random server
+  initialization state may have been used to signal the relay agent
+  information options sub-option code for the 'END' of the option space.
+
 			Changes since 4.0.0b3
 
 - The reverse dns name for PTR updates on IPv6 addresses has been fixed to
diff --git a/common/tables.c b/common/tables.c
index 46874207..9259332d 100644
--- a/common/tables.c
+++ b/common/tables.c
@@ -961,6 +961,7 @@ void initialize_common_option_spaces()
 	dhcp_universe.store_tag = putUChar;
 	dhcp_universe.get_length = getUChar;
 	dhcp_universe.store_length = putUChar;
+	dhcp_universe.site_code_min = 0;
 	dhcp_universe.end = DHO_END;
 	dhcp_universe.index = universe_count++;
 	universes [dhcp_universe.index] = &dhcp_universe;
@@ -1001,6 +1002,7 @@ void initialize_common_option_spaces()
 	nwip_universe.store_tag = putUChar;
 	nwip_universe.get_length = getUChar;
 	nwip_universe.store_length = putUChar;
+	nwip_universe.site_code_min = 0;
 	nwip_universe.end = 0;
 	code = DHO_NWIP_SUBOPTIONS;
 	nwip_universe.enc_opt = NULL;
@@ -1046,6 +1048,7 @@ void initialize_common_option_spaces()
 	fqdn_universe.store_tag = putUChar;
 	fqdn_universe.get_length = getUChar;
 	fqdn_universe.store_length = putUChar;
+	fqdn_universe.site_code_min = 0;
 	fqdn_universe.end = 0;
 	fqdn_universe.index = universe_count++;
 	code = DHO_FQDN;
@@ -1093,6 +1096,7 @@ void initialize_common_option_spaces()
         vendor_class_universe.store_tag = putULong;
 	vendor_class_universe.get_length = getUChar;
         vendor_class_universe.store_length = putUChar;
+	vendor_class_universe.site_code_min = 0;
 	vendor_class_universe.end = 0;
 	code = DHO_VIVCO_SUBOPTIONS;
 	vendor_class_universe.enc_opt = NULL;
@@ -1139,6 +1143,7 @@ void initialize_common_option_spaces()
         vendor_universe.store_tag = putULong;
 	vendor_universe.get_length = getUChar;
         vendor_universe.store_length = putUChar;
+	vendor_universe.site_code_min = 0;
 	vendor_universe.end = 0;
 	code = DHO_VIVSO_SUBOPTIONS;
 	vendor_universe.enc_opt = NULL;
@@ -1185,6 +1190,7 @@ void initialize_common_option_spaces()
         isc_universe.store_tag = putUShort;
 	isc_universe.get_length = getUShort;
         isc_universe.store_length = putUShort;
+	isc_universe.site_code_min = 0;
 	isc_universe.end = 0;
 	code = VENDOR_ISC_SUBOPTIONS;
 	isc_universe.enc_opt = NULL;
@@ -1230,6 +1236,7 @@ void initialize_common_option_spaces()
 	dhcpv6_universe.store_tag = putUShort;
 	dhcpv6_universe.get_length = getUShort;
 	dhcpv6_universe.store_length = putUShort;
+	dhcpv6_universe.site_code_min = 0;
 	/* DHCPv6 has no END option. */
 	dhcpv6_universe.end = 0x00;
 	dhcpv6_universe.index = universe_count++;
@@ -1270,6 +1277,7 @@ void initialize_common_option_spaces()
 	vsio_universe.store_tag = putULong;
 	vsio_universe.get_length = NULL;
 	vsio_universe.store_length = NULL;
+	vsio_universe.site_code_min = 0;
 	/* No END option. */
 	vsio_universe.end = 0x00;
 	code = D6O_VENDOR_OPTS;
@@ -1310,6 +1318,7 @@ void initialize_common_option_spaces()
 	isc6_universe.store_tag = putULong;
 	isc6_universe.get_length = NULL;
 	isc6_universe.store_length = NULL;
+	isc6_universe.site_code_min = 0;
 	/* No END option. */
 	isc6_universe.end = 0x00;
 	code = 2495;
@@ -1353,6 +1362,7 @@ void initialize_common_option_spaces()
 	fqdn6_universe.store_tag = NULL;
 	fqdn6_universe.get_length = NULL;
 	fqdn6_universe.store_length = NULL;
+	fqdn6_universe.site_code_min = 0;
 	fqdn6_universe.end = 0;
 	fqdn6_universe.index = universe_count++;
 	code = D6O_CLIENT_FQDN;
diff --git a/includes/tree.h b/includes/tree.h
index ef8f3baf..2df11ceb 100644
--- a/includes/tree.h
+++ b/includes/tree.h
@@ -334,7 +334,7 @@ struct universe {
 	u_int32_t (*get_length) (const unsigned char *);
 	void (*store_length) PROTO ((unsigned char *, u_int32_t));
 	int tag_size, length_size;
-	unsigned end;
+	unsigned site_code_min, end;
 	option_name_hash_t *name_hash;
 	option_code_hash_t *code_hash;
 	struct option *enc_opt;
diff --git a/server/dhcp.c b/server/dhcp.c
index 65c55860..3b8d2cb4 100644
--- a/server/dhcp.c
+++ b/server/dhcp.c
@@ -39,6 +39,10 @@
 int outstanding_pings;
 
 static char dhcp_message [256];
+static int site_code_min;
+
+static int find_min_site_code(struct universe *);
+static isc_result_t lowest_site_code(const void *, unsigned, void *);
 
 static const char *dhcp_type_names [] = { 
 	"DHCPDISCOVER",
@@ -1136,7 +1140,7 @@ void dhcpinform (packet, ms_nulltp)
 		}
 
 		options -> site_universe = u -> index;
-		options -> site_code_min = 224; /* From RFC3942 */
+		options->site_code_min = find_min_site_code(u);
 		data_string_forget (&d1, MDL);
 	} else {
 		options -> site_universe = dhcp_universe.index;
@@ -2732,7 +2736,7 @@ void ack_lease (packet, lease, offer, when, msg, ms_nulltp, hp)
 		}
 
 		state -> options -> site_universe = u -> index;
-		state -> options -> site_code_min = 224; /* From RFC3942 */
+		state->options->site_code_min = find_min_site_code(u);
 		data_string_forget (&d1, MDL);
 	} else {
 		state -> options -> site_code_min = 0;
@@ -4028,3 +4032,65 @@ get_server_source_address(struct in_addr *from,
 	}
 }
 
+/*
+ * Look for the lowest numbered site code number and
+ * apply a log warning if it is less than 224.  Do not
+ * permit site codes less than 128 (old code never did).
+ *
+ * Note that we could search option codes 224 down to 128
+ * on the hash table, but the table is (probably) smaller
+ * than that if it was declared as a standalone table with
+ * defaults.  So we traverse the option code hash.
+ */
+static int
+find_min_site_code(struct universe *u)
+{
+	if (u->site_code_min)
+		return u->site_code_min;
+
+	/*
+	 * Note that site_code_min has to be global as we can't pass an
+	 * argument through hash_foreach().  The value 224 is taken from
+	 * RFC 3942.
+	 */
+	site_code_min = 224;
+	option_code_hash_foreach(u->code_hash, lowest_site_code);
+
+	if (site_code_min < 224) {
+		log_error("WARNING: site-local option codes less than 224 have "
+			  "been deprecated by RFC3942.  You have options "
+			  "listed in site local space %s that number as low as "
+			  "%d.  Please investigate if these should be declared "
+			  "as regular options rather than site-local options, "
+			  "or migrated up past 224.",
+			  u->name, site_code_min);
+	}
+
+	/*
+	 * don't even bother logging, this is just silly, and never worked
+	 * on any old version of software.
+	 */
+	if (site_code_min < 128)
+		site_code_min = 128;
+
+	/*
+	 * Cache the determined minimum site code on the universe structure.
+	 * Note that due to the < 128 check above, a value of zero is
+	 * impossible.
+	 */
+	u->site_code_min = site_code_min;
+
+	return site_code_min;
+}
+
+static isc_result_t
+lowest_site_code(const void *key, unsigned len, void *object)
+{
+	struct option *option = object;
+
+	if (option->code < site_code_min)
+		site_code_min = option->code;
+
+	return ISC_R_SUCCESS;
+}
+
diff --git a/server/stables.c b/server/stables.c
index 3e1dffdc..a2d76c79 100644
--- a/server/stables.c
+++ b/server/stables.c
@@ -347,6 +347,8 @@ void initialize_server_option_spaces()
 	agent_universe.store_tag = putUChar;
 	agent_universe.get_length = getUChar;
 	agent_universe.store_length = putUChar;
+	agent_universe.site_code_min = 0;
+	agent_universe.end = 0;
 	universes [agent_universe.index] = &agent_universe;
 	if (!option_name_new_hash(&agent_universe.name_hash,
 				  AGENT_HASH_SIZE, MDL) ||
@@ -385,6 +387,8 @@ void initialize_server_option_spaces()
 	server_universe.tag_size = 4;
 	server_universe.store_tag = putUChar;
 	server_universe.store_length = putUChar;
+	server_universe.site_code_min = 0;
+	server_universe.end = 0;
 	server_universe.index = universe_count++;
 	universes [server_universe.index] = &server_universe;
 	if (!option_name_new_hash(&server_universe.name_hash,