[master] Fixed infinite-is-reserved and lease:flags setting via omapi

Merges in rt31179.

RELNOTES

@@ -600,6 +600,13 @@ by Eric Young (eay@cryptsoft.com).
   (typically 1) in the outbound upstream packets.
   [ISC-Bugs #37426]
 
+- The server will now correctly treat a lease as reserved when the client
+  requests an infinite lease time (i.e. OxFFFFFFFF) and "infinite-is-reserved"
+  is enabled.  Prior to this the server would halt.  In addition, corrections
+  were made to the server to allow a lease's flags field to be set via omapi.
+  Prior to this, the server, depending on the host architecture,  would
+  incorrectly parse the new flags value from the omapi message.
+  [ISC-Bugs #31179]
 
 			Changes since 4.3.1b1
 

server/dhcp.c

@@ -3,7 +3,7 @@
    DHCP Protocol engine. */
 
 /*
- * Copyright (c) 2004-2015 by Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (c) 2004-2016 by Internet Systems Consortium, Inc. ("ISC")
  * Copyright (c) 1995-2003 by Internet Software Consortium
  *
  * Permission to use, copy, modify, and distribute this software for any
@@ -2909,7 +2909,17 @@ void ack_lease (packet, lease, offer, when, msg, ms_nulltp, hp)
 	memcpy (&lt -> hardware_addr.hbuf [1], packet -> raw -> chaddr,
 		sizeof packet -> raw -> chaddr);
 
-	lt -> flags = lease -> flags & ~PERSISTENT_FLAGS;
+	/*
+	 * If client has requested the lease become infinite, then it
+	 * doens't qualify for reuse even if it's younger than the
+	 * dhcp-cache-threshold.
+	 */
+	if ((lt->flags & RESERVED_LEASE) && !(lease->flags & RESERVED_LEASE)) {
+		log_debug ("Cannot reuse: lease is changing to RESERVED");
+		lease->cannot_reuse = 1;
+	}
+
+	lt->flags |= lease->flags & ~PERSISTENT_FLAGS;
 
 	/* If there are statements to execute when the lease is
 	   committed, execute them. */

server/mdb.c

@@ -3,7 +3,7 @@
    Server-specific in-memory database support. */
 
 /*
- * Copyright (c) 2011-2015 by Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (c) 2011-2016 by Internet Systems Consortium, Inc. ("ISC")
  * Copyright (c) 2004-2009 by Internet Systems Consortium, Inc. ("ISC")
  * Copyright (c) 1996-2003 by Internet Software Consortium
  *
@@ -1136,7 +1136,6 @@ int supersede_lease (comp, lease, commit, propogate, pimmediate, from_pool)
 	if (pimmediate && !commit)
 		return 0;
 #endif
-
 	/* If there is no sample lease, just do the move. */
 	if (!lease)
 		goto just_move_it;
@@ -1223,8 +1222,6 @@ int supersede_lease (comp, lease, commit, propogate, pimmediate, from_pool)
 		host_dereference (&comp -> host, MDL);
 	host_reference (&comp -> host, lease -> host, MDL);
 	comp -> hardware_addr = lease -> hardware_addr;
-	comp -> flags = ((lease -> flags & ~PERSISTENT_FLAGS) |
-			 (comp -> flags & ~EPHEMERAL_FLAGS));
 	if (comp -> scope)
 		binding_scope_dereference (&comp -> scope, MDL);
 	if (lease -> scope) {
@@ -1375,6 +1372,14 @@ int supersede_lease (comp, lease, commit, propogate, pimmediate, from_pool)
 	   timer sequence. */
 	LEASE_REMOVEP(lq, comp);
 
+	/* Now that we've done the flag-affected queue removal
+	 * we can update the new lease's flags, if there's an
+	 * existing lease */
+	if (lease) {
+		comp->flags = ((lease->flags & ~PERSISTENT_FLAGS) |
+				(comp->flags & ~EPHEMERAL_FLAGS));
+	}
+
 	/* Make the state transition. */
 	if (commit || !pimmediate)
 		make_binding_state_transition (comp);

server/omapi.c

@@ -3,7 +3,7 @@
    OMAPI object interfaces for the DHCP server. */
 
 /*
- * Copyright (c) 2012-2015 by Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (c) 2012-2016 by Internet Systems Consortium, Inc. ("ISC")
  * Copyright (c) 2004-2009 by Internet Systems Consortium, Inc. ("ISC")
  * Copyright (c) 1999-2003 by Internet Software Consortium
  *
@@ -41,6 +41,9 @@ static isc_result_t class_lookup (omapi_object_t **,
 				  omapi_object_t *, omapi_object_t *,
 				  omapi_object_type_t *);
 
+static isc_result_t update_lease_flags(struct lease* lease,
+				       omapi_typed_data_t *value);
+
 omapi_object_type_t *dhcp_type_lease;
 omapi_object_type_t *dhcp_type_pool;
 omapi_object_type_t *dhcp_type_class;
@@ -269,22 +272,7 @@ isc_result_t dhcp_lease_set_value  (omapi_object_t *h,
 		      piaddr(lease->ip_addr), old_lease_end, lease_end);
 	    return ISC_R_IOERROR;
 	} else if (!omapi_ds_strcmp(name, "flags")) {
-	    u_int8_t oldflags;
+	    return (update_lease_flags(lease, value));
-
-	    if (value->type != omapi_datatype_data)
-		return DHCP_R_INVALIDARG;
-
-	    oldflags = lease->flags;
-	    lease->flags = (value->u.buffer.value[0] & EPHEMERAL_FLAGS) |
-			   (lease->flags & ~EPHEMERAL_FLAGS);
-	    if(oldflags == lease->flags)
-		return ISC_R_SUCCESS;
-	    if (!supersede_lease(lease, NULL, 1, 1, 1, 0)) {
-		log_error("Failed to update flags for lease %s.",
-			  piaddr(lease->ip_addr));
-		return ISC_R_IOERROR;
-	    }
-	    return ISC_R_SUCCESS;
 	} else if (!omapi_ds_strcmp (name, "billing-class")) {
 	    return DHCP_R_UNCHANGED;	/* XXX carefully allow change. */
 	} else if (!omapi_ds_strcmp (name, "hardware-address")) {
@@ -321,6 +309,85 @@ isc_result_t dhcp_lease_set_value  (omapi_object_t *h,
 	return ISC_R_IOERROR;
 }
 
+/*
+ * \brief Updates the lease's flags to a given value
+ *
+ * In order to update the lease's flags, we make a copy of the
+ * lease, and update the copy's flags with the new value.
+ * We then use the updated copy as the second parameter to a
+ * call to supersede_lease().  This ensures that the lease
+ * moves between queues correctly.   This is critical when
+ * the RESERVED_LEASE flag is being changed.
+ *
+ * Note that only the EPHEMERAL flags are permitted to be changed.
+ *
+ * \param lease - pointer to the lease to update
+ * \param value - omapi data value containing the new flags value
+ *
+ * \return ISC_R_SUCCESS if the lease was successfully updated,
+ *  DHCP_R_UNCHANGED if new value would result in no change to the
+ *  lease's flags, or an appropriate status on other errors
+ */
+static isc_result_t update_lease_flags(struct lease* lease,
+				       omapi_typed_data_t *value)
+{
+	u_int8_t oldflags;
+	u_int8_t newflags;
+	struct lease* lupdate = NULL;
+	isc_result_t status;
+
+	/* Grab the requested flags value. We (the server) send flags
+	 * out as 1-byte, so we expect clients to do the same.  However
+	 * omshell, will send a network-ordered 4 byte integer if the
+	 * input is "set flags = <n>", so we'll accomdate that too. */
+	if (value->u.buffer.len == 1) {
+		newflags = value->u.buffer.value[0];
+	} else {
+		unsigned long tmp;
+
+		status = omapi_get_int_value (&tmp, value);
+		if (status != ISC_R_SUCCESS) {
+			return (status);
+		}
+
+		newflags = (u_int8_t)tmp;
+	}
+
+	/* Save off the current flags value. */
+	oldflags = lease->flags;
+
+	/* The new value must preserve all PERSISTANT_FLAGS */
+	newflags = ((lease->flags & ~EPHEMERAL_FLAGS) |
+		    (newflags & EPHEMERAL_FLAGS));
+
+	/* If there's no net change, we're done */
+	if (oldflags == newflags) {
+		return (DHCP_R_UNCHANGED);
+	}
+
+	/* Make a copy of the lease. */
+	if (!lease_copy(&lupdate, lease, MDL)) {
+		return (ISC_R_FAILURE);
+	}
+
+	/* Set the copy's flags to the new value */
+	lupdate->flags = newflags;
+
+	/* Attempt to update the lease */
+	if (!supersede_lease(lease, lupdate, 1, 1, 1, 0)) {
+		log_error("Failed to update flags for lease %s.",
+			  piaddr(lease->ip_addr));
+		status = ISC_R_FAILURE;
+	} else {
+		log_debug ("lease flags changed from  %x to %x for lease %s.",
+			   oldflags, newflags, piaddr(lease->ip_addr));
+		status = ISC_R_SUCCESS;
+	}
+
+	lease_dereference(&lupdate, MDL);
+	return (status);
+}
+
 
 isc_result_t dhcp_lease_get_value (omapi_object_t *h, omapi_object_t *id,
 				   omapi_data_string_t *name,