X-Git-Url: https://git.distorted.org.uk/~mdw/zone/blobdiff_plain/1c472e03951aeaf721c6043f5bdaf5acaf0f4941..01be91612cfa32134d22e4d8652dff0985625984:/zone.lisp

diff --git a/zone.lisp b/zone.lisp
index e83aa75..1d7e18d 100644
--- a/zone.lisp
+++ b/zone.lisp
@@ -13,27 +13,22 @@
 ;;; it under the terms of the GNU General Public License as published by
 ;;; the Free Software Foundation; either version 2 of the License, or
 ;;; (at your option) any later version.
-;;; 
+;;;
 ;;; 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
+;;;--------------------------------------------------------------------------
+;;; Packaging.
+
 (defpackage #:zone
-  (:use #:common-lisp #:mdw.base #:mdw.str #:mdw.collect #:mdw.safely)
-  (:export #:ipaddr #:string-ipaddr #:ipaddr-byte #:ipaddr-string #:ipaddrp
-	   #:integer-netmask #:ipmask #:ipmask-cidl-slash #:make-ipnet
-	     #:string-ipnet #:ipnet #:ipnet-net #:ipnet-mask #:with-ipnet
-	     #:ipnet-pretty #:ipnet-string #:ipnet-broadcast #:ipnet-hosts
-	     #:ipnet-host #:ipaddr-networkp #:ipnet-subnetp
-	   #:host-find# #:host-create #:defhost #:parse-ipaddr
-	     #:net #:net-find #:net-get-as-ipnet #:net-create #:defnet
-	     #:net-next-host #:net-host
-	   #:soa #:mx #:zone #:zone-record #:zone-subdomain
+  (:use #:common-lisp #:mdw.base #:mdw.str #:collect #:safely #:net)
+  (:export #:soa #:mx #:zone #:zone-record #:zone-subdomain
 	   #:*default-zone-source* #:*default-zone-refresh*
 	     #:*default-zone-retry* #:*default-zone-expire*
 	     #:*default-zone-min-ttl* #:*default-zone-ttl*
@@ -42,293 +37,41 @@
 	     #:defrevzone #:zone-save
 	   #:defzoneparse #:zone-parse-host
 	   #:timespec-seconds #:make-zone-serial))
+
 (in-package #:zone)
 
-(defun mask (n)
-  "Return 2^N - 1: i.e., a mask of N set bits."
-  (1- (ash 1 n)))
-(deftype u32 ()
-  "The type of unsigned 32-bit values."
-  '(unsigned-byte 32))
-(deftype ipaddr ()
-  "The type of IP (version 4) addresses."
-  'u32)
-
-(defun string-ipaddr (str &key (start 0) (end nil))
-  "Parse STR as an IP address in dotted-quad form and return the integer
-equivalent.  STR may be anything at all: it's converted as if by
-`stringify'.  The START and END arguments may be used to parse out a
-substring."
-  (setf str (stringify str))
-  (unless end
-    (setf end (length str)))
-  (let ((addr 0) (noct 0))
-    (loop
-      (let* ((pos (position #\. str :start start :end end))
-	     (i (parse-integer str :start start :end (or pos end))))
-	(unless (<= 0 i 256)
-	  (error "IP address octet out of range"))
-	(setf addr (+ (* addr 256) i))
-	(incf noct)
-	(unless pos
-	  (return))
-	(setf start (1+ pos))))
-    (unless (= noct 4)
-      (error "Wrong number of octets in IP address"))
-    addr))
-(defun ipaddr-byte (ip n)
-  "Return byte N (from most significant downwards) of an IP address."
-  (assert (<= 0 n 3))
-  (logand #xff (ash ip (* -8 (- 3 n)))))
-(defun ipaddr-string (ip)
-  "Transform the address IP into a string in dotted-quad form."
-  (check-type ip ipaddr)
-  (join-strings #\. (collecting ()
-		      (dotimes (i 4)
-			(collect (ipaddr-byte ip i))))))
-(defun ipaddrp (ip)
-  "Answer true if IP is a valid IP address in integer form."
-  (typep ip 'ipaddr))
-(defun ipaddr (ip)
-  "Convert IP to an IP address.  If it's an integer, return it unchanged;
-otherwise convert by `string-ipaddr'."
-  (typecase ip
-    (ipaddr ip)
-    (t (string-ipaddr ip))))
-
-(defun integer-netmask (i)
-  "Given an integer I, return a netmask with its I top bits set."
-  (- (ash 1 32) (ash 1 (- 32 i))))
-(defun ipmask (ip)
-  "Transform IP into a netmask.  If it's a small integer then it's converted
-by `integer-netmask'; if nil, then all-bits-set; otherwise convert using
-`ipaddr'."
-  (typecase ip
-    (null (mask 32))
-    ((integer 0 32) (integer-netmask ip))
-    (t (ipaddr ip))))
-(defun ipmask-cidl-slash (mask)
-  "Given a netmask MASK, return an integer N such that (integer-netmask N) =
-MASK, or nil if this is impossible."
-  (dotimes (i 33)
-    (when (= mask (integer-netmask i))
-      (return i))))
-
-(defun make-ipnet (net mask)
-  "Construct an IP-network object given the NET and MASK; these are
-transformed as though by `ipaddr' and `ipmask'."
-  (let ((net (ipaddr net))
-	(mask (ipmask mask)))
-    (cons (logand net mask) mask)))
-(defun string-ipnet (str &key (start 0) (end nil))
-  "Parse an IP-network from the string STR."
-  (setf str (stringify str))
-  (unless end (setf end (length str)))
-  (let ((sl (position #\/ str :start start :end end)))
-    (if sl
-	(make-ipnet (parse-ipaddr (subseq str start sl))
-		    (if (find #\. str :start (1+ sl) :end end)
-			(string-ipaddr str :start (1+ sl) :end end)
-			(integer-netmask (parse-integer str
-							:start (1+ sl)
-							:end end))))
-	(make-ipnet (parse-ipaddr (subseq str start end))
-		    (integer-netmask 32)))))
-(defun ipnet (net &optional mask)
-  "Construct an IP-network object from the given arguments.  A number of
-forms are acceptable:
-
-  * NET MASK -- as for `make-ipnet'.
-  * ADDR -- a single address (equivalent to ADDR 32)
-  * (NET . MASK|nil) -- a single-object representation.
-  * IPNET -- return an equivalent (`equal', not necessarily `eql') version."
-  (cond (mask (make-ipnet net mask))
-	((or (stringp net) (symbolp net)) (string-ipnet net))
-	(t (apply #'make-ipnet (pairify net 32)))))
-(defun ipnet-net (ipn)
-  "Return the base network address of IPN."
-  (car ipn))
-(defun ipnet-mask (ipn)
-  "Return the netmask of IPN."
-  (cdr ipn))
-(defmacro with-ipnet ((net mask) ipn &body body)
-  "Evaluate BODY with NET and MASK bound to the base address and netmask of
-IPN.  Either NET or MASK (or, less usefully, both) may be nil if not wanted."
-  (with-gensyms tmp
-    `(let ((,tmp ,ipn))
-       (let (,@(and net `((,net (ipnet-net ,tmp))))
-	     ,@(and mask `((,mask (ipnet-mask ,tmp)))))
-	 ,@body))))
-(defun ipnet-pretty (ipn)
-  "Convert IPN to a pretty cons-cell form."
-  (with-ipnet (net mask) ipn
-    (cons (ipaddr-string net)
-	  (or (ipmask-cidl-slash mask) (ipaddr-string mask)))))
-(defun ipnet-string (ipn)
-  "Convert IPN to a string."
-  (with-ipnet (net mask) ipn
-    (format nil "~A/~A"
-	    (ipaddr-string net)
-	    (or (ipmask-cidl-slash mask) (ipaddr-string mask)))))
-(defun ipnet-broadcast (ipn)
-  "Return the broadcast address for the network IPN."
-  (with-ipnet (net mask) ipn
-    (logior net (logxor (mask 32) mask))))
-(defun ipnet-hosts (ipn)
-  "Return the number of available addresses in network IPN."
-  (ash 1 (- 32 (logcount (ipnet-mask ipn)))))
-(defun ipnet-host (ipn host)
-  "Return the address of the given HOST in network IPN.  This works even with
-a non-contiguous netmask."
-  (check-type host u32)
-  (with-ipnet (net mask) ipn
-    (let ((i 0) (m 1) (a net) (h host))
-      (loop
-        (when (>= i 32)
-	  (error "Host index ~D out of range for network ~A"
-		 host (ipnet-pretty ipn)))
-        (cond ((zerop h)
-	       (return a))
-	      ((logbitp i mask)
-	       (setf h (ash h 1)))
-	      (t
-	       (setf a (logior a (logand m h)))
-	       (setf h (logandc2 h m))))
-	(setf m (ash m 1))
-	(incf i)))))
-(defun ipaddr-networkp (ip ipn)
-  "Returns true if address IP is within network IPN."
-  (with-ipnet (net mask) ipn
-    (= net (logand ip mask))))
-(defun ipnet-subnetp (ipn subn)
-  "Returns true if SUBN is a (non-strict) subnet of IPN."
-  (with-ipnet (net mask) ipn
-    (with-ipnet (subnet submask) subn
-      (and (= net (logand subnet mask))
-	   (= submask (logior mask submask))))))
-
-(defun resolve-hostname (name)
-  "Resolve a hostname to an IP address using the DNS, or return nil."
-  (let ((he (ext:lookup-host-entry name)))
-    (and he
-	 (ext:host-entry-addr he))))
-(defun canonify-hostname (name)
-  "Resolve a hostname to canonical form using the DNS, or return nil."
-  (let ((he (ext:lookup-host-entry name)))
-    (and he
-	 (ext:host-entry-name he))))
-(defun parse-ipaddr (addr)
-  "Convert the string ADDR into an IP address: tries all sorts of things:
-
-  (NET [INDEX]) -- index a network: NET is a network name defined by defnet;
-    INDEX is an index or one of the special symbols understood by net-host,
-    and defaults to :next
-  INTEGER -- an integer IP address
-  IPADDR -- an IP address in dotted-quad form
-  HOST -- a host name defined by defhost
-  DNSNAME -- a name string to look up in the DNS"
-  (cond ((listp addr)
-	 (destructuring-bind
-	     (net host)
-	     (pairify addr :next)
-	   (net-host (or (net-find net)
-			 (error "Network ~A not found" net))
-		     host)))
-	((ipaddrp addr) addr)
-	(t
-	 (setf addr (string-downcase (stringify addr)))
-	 (or (host-find addr)
-	     (and (plusp (length addr))
-		  (digit-char-p (char addr 0))
-		  (string-ipaddr addr))
-	     (resolve-hostname (stringify addr))
-	     (error "Host name ~A unresolvable" addr)))))
-
-(defvar *hosts* (make-hash-table :test #'equal)
-  "The table of known hostnames.")
-(defun host-find (name)
-  "Find a host by NAME."
-  (gethash (string-downcase (stringify name)) *hosts*))
-(defun (setf host-find) (addr name)
-  "Make NAME map to ADDR (must be an ipaddr in integer form)."
-  (setf (gethash (string-downcase (stringify name)) *hosts*) addr))
-(defun host-create (name addr)
-  "Make host NAME map to ADDR (anything acceptable to parse-ipaddr)."
-  (setf (host-find name) (parse-ipaddr addr)))
-(defmacro defhost (name addr)
-  "Main host definition macro.  Neither NAME nor ADDR is evaluated."
-  `(progn
-     (host-create ',name ',addr)
-     ',name))
-
-(defstruct (net (:predicate netp))
-  "A network structure.  Slots:
-
-NAME       The network's name, as a string
-IPNET      The network base address and mask
-HOSTS      Number of hosts in the network
-NEXT       Index of the next unassigned host"
-  name
-  ipnet
-  hosts
-  next)
-
-(defvar *networks* (make-hash-table :test #'equal)
-  "The table of known networks.")
-(defun net-find (name)
-  "Find a network by NAME."
-  (gethash (string-downcase (stringify name)) *networks*))
-(defun (setf net-find) (net name)
-  "Make NAME map to NET."
-  (setf (gethash (string-downcase (stringify name)) *networks*) net))
-(defun net-get-as-ipnet (form)
-  "Transform FORM into an ipnet.  FORM may be a network name, or something
-acceptable to the ipnet function."
-  (let ((net (net-find form)))
-    (if net (net-ipnet net)
-	(ipnet form))))
-(defun net-create (name &rest args)
-  "Construct a new network called NAME and add it to the map.  The ARGS
-describe the new network, in a form acceptable to the ipnet function."
-  (let ((ipn (apply #'ipnet args)))
-    (setf (net-find name)
-	  (make-net :name (string-downcase (stringify name))
-		    :ipnet ipn
-		    :hosts (ipnet-hosts ipn)
-		    :next 1))))
-(defmacro defnet (name &rest args)
-  "Main network definition macro.  Neither NAME nor any of the ARGS is
-evaluated."
-  `(progn
-     (net-create ',name ,@(mapcar (lambda (x) `',x) args))
-     ',name))
-(defun net-next-host (net)
-  "Given a NET, return the IP address (as integer) of the next available
-address in the network."
-  (unless (< (net-next net) (net-hosts net))
-    (error "No more hosts left in network ~A" (net-name net)))
-  (let ((next (net-next net)))
-    (incf (net-next net))
-    (net-host net next)))
-(defun net-host (net host)
-  "Return the given HOST on the NEXT.  HOST may be an index (in range, of
-course), or one of the keywords:
-:NEXT       next host, as by net-next-host
-:NET        network base address
-:BROADCAST  network broadcast address"
-  (case host
-    (:next (net-next-host net))
-    (:net (ipnet-net (net-ipnet net)))
-    (:broadcast (ipnet-broadcast (net-ipnet net)))
-    (t (ipnet-host (net-ipnet net) host))))
+;;;--------------------------------------------------------------------------
+;;; Various random utilities.
 
 (defun to-integer (x)
   "Convert X to an integer in the most straightforward way."
   (floor (rational x)))
+
+(defun from-mixed-base (base val)
+  "BASE is a list of the ranges for the `digits' of a mixed-base
+   representation.  Convert VAL, a list of digits, into an integer."
+  (do ((base base (cdr base))
+       (val (cdr val) (cdr val))
+       (a (car val) (+ (* a (car base)) (car val))))
+      ((or (null base) (null val)) a)))
+
+(defun to-mixed-base (base val)
+  "BASE is a list of the ranges for the `digits' of a mixed-base
+   representation.  Convert VAL, an integer, into a list of digits."
+  (let ((base (reverse base))
+	(a nil))
+    (loop
+      (unless base
+	(push val a)
+	(return a))
+      (multiple-value-bind (q r) (floor val (pop base))
+	(push r a)
+	(setf val q)))))
+
 (defun timespec-seconds (ts)
   "Convert a timespec TS to seconds.  A timespec may be a real count of
-seconds, or a list (COUNT UNIT): UNIT may be any of a number of obvious time
-units."
+   seconds, or a list (COUNT UNIT): UNIT may be any of a number of obvious
+   time units."
   (cond ((null ts) 0)
 	((realp ts) (floor ts))
 	((atom ts)
@@ -349,6 +92,33 @@ units."
 					 (cadr ts))))))
 	      (timespec-seconds (cddr ts))))))
 
+(defun hash-table-keys (ht)
+  "Return a list of the keys in hashtable HT."
+  (collecting ()
+    (maphash (lambda (key val) (declare (ignore val)) (collect key)) ht)))
+
+(defun iso-date (&optional time &key datep timep (sep #\ ))
+  "Construct a textual date or time in ISO format.  The TIME is the universal
+   time to convert, which defaults to now; DATEP is whether to emit the date;
+   TIMEP is whether to emit the time, and SEP (default is space) is how to
+   separate the two."
+  (multiple-value-bind
+      (sec min hr day mon yr dow dstp tz)
+      (decode-universal-time (if (or (null time) (eq time :now))
+				 (get-universal-time)
+				 time))
+    (declare (ignore dow dstp tz))
+    (with-output-to-string (s)
+      (when datep
+	(format s "~4,'0D-~2,'0D-~2,'0D" yr mon day)
+	(when timep
+	  (write-char sep s)))
+      (when timep
+	(format s "~2,'0D:~2,'0D:~2,'0D" hr min sec)))))
+
+;;;--------------------------------------------------------------------------
+;;; Zone types.
+
 (defstruct (soa (:predicate soap))
   "Start-of-authority record information."
   source
@@ -358,10 +128,12 @@ units."
   expire
   min-ttl
   serial)
+
 (defstruct (mx (:predicate mxp))
   "Mail-exchange record information."
   priority
   domain)
+
 (defstruct (zone (:predicate zonep))
   "Zone information."
   soa
@@ -369,48 +141,51 @@ units."
   name
   records)
 
+;;;--------------------------------------------------------------------------
+;;; Zone defaults.  It is intended that scripts override these.
+
+#+ecl
+(cffi:defcfun gethostname :int
+  (name :pointer)
+  (len :uint))
+
 (defvar *default-zone-source*
-  (let ((hn (unix:unix-gethostname)))
+  (let ((hn #+cmu (unix:unix-gethostname)
+	    #+clisp (unix:get-host-name)
+	    #+ecl (cffi:with-foreign-pointer-as-string (buffer 256 len)
+		    (let ((rc (gethostname buffer len)))
+		      (unless (zerop rc)
+			(error "gethostname(2) failed (rc = ~A)." rc))))))
     (and hn (concatenate 'string (canonify-hostname hn) ".")))
   "The default zone source: the current host's name.")
+
 (defvar *default-zone-refresh* (* 24 60 60)
   "Default zone refresh interval: one day.")
+
 (defvar *default-zone-admin* nil
   "Default zone administrator's email address.")
+
 (defvar *default-zone-retry* (* 60 60)
   "Default znoe retry interval: one hour.")
+
 (defvar *default-zone-expire* (* 14 24 60 60)
   "Default zone expiry time: two weeks.")
+
 (defvar *default-zone-min-ttl* (* 4 60 60)
   "Default zone minimum TTL/negative TTL: four hours.")
+
 (defvar *default-zone-ttl* (* 8 60 60)
   "Default zone TTL (for records without explicit TTLs): 8 hours.")
+
 (defvar *default-mx-priority* 50
   "Default MX priority.")
 
-(defun from-mixed-base (base val)
-  "BASE is a list of the ranges for the `digits' of a mixed-base
-representation.  Convert VAL, a list of digits, into an integer."
-  (do ((base base (cdr base))
-       (val (cdr val) (cdr val))
-       (a (car val) (+ (* a (car base)) (car val))))
-      ((or (null base) (null val)) a)))
-(defun to-mixed-base (base val)
-  "BASE is a list of the ranges for the `digits' of a mixed-base
-representation.  Convert VAL, an integer, into a list of digits."
-  (let ((base (reverse base))
-	(a nil))
-    (loop
-      (unless base
-	(push val a)
-	(return a))
-      (multiple-value-bind (q r) (floor val (pop base))
-	(push r a)
-	(setf val q)))))
+;;;--------------------------------------------------------------------------
+;;; Serial numbering.
 
 (defun make-zone-serial (name)
   "Given a zone NAME, come up with a new serial number.  This will (very
-carefully) update a file ZONE.serial in the current directory."
+   carefully) update a file ZONE.serial in the current directory."
   (let* ((file (format nil "~(~A~).serial" name))
 	 (last (with-open-file (in file
 				   :direction :input
@@ -434,11 +209,16 @@ carefully) update a file ZONE.serial in the current directory."
 	      (cons seq now)))
     (from-mixed-base '(100 100 100) (reverse (cons seq now)))))
 
+;;;--------------------------------------------------------------------------
+;;; Zone variables and structures.
+
 (defvar *zones* (make-hash-table :test #'equal)
   "Map of known zones.")
+
 (defun zone-find (name)
   "Find a zone given its NAME."
   (gethash (string-downcase (stringify name)) *zones*))
+
 (defun (setf zone-find) (zone name)
   "Make the zone NAME map to ZONE."
   (setf (gethash (string-downcase (stringify name)) *zones*) zone))
@@ -453,14 +233,17 @@ carefully) update a file ZONE.serial in the current directory."
 
 (defstruct (zone-subdomain (:conc-name zs-))
   "A subdomain.  Slightly weird.  Used internally by zone-process-records
-below, and shouldn't escape."
+   below, and shouldn't escape."
   name
   ttl
   records)
 
+;;;--------------------------------------------------------------------------
+;;; Zone infrastructure.
+
 (defun zone-process-records (rec ttl func)
   "Sort out the list of records in REC, calling FUNC for each one.  TTL is
-the default time-to-live for records which don't specify one."
+   the default time-to-live for records which don't specify one."
   (labels ((sift (rec ttl)
 	     (collecting (top sub)
 	       (loop
@@ -510,7 +293,7 @@ the default time-to-live for records which don't specify one."
 
 (defun zone-parse-host (f zname)
   "Parse a host name F: if F ends in a dot then it's considered absolute;
-otherwise it's relative to ZNAME."
+   otherwise it's relative to ZNAME."
   (setf f (stringify f))
   (cond ((string= f "@") (stringify zname))
 	((and (plusp (length f))
@@ -518,13 +301,9 @@ otherwise it's relative to ZNAME."
 	 (string-downcase (subseq f 0 (1- (length f)))))
 	(t (string-downcase (concatenate 'string f "."
 					 (stringify zname))))))
-(defun ipnet-changeable-bytes (mask)
-  "Answers how many low-order bytes of MASK are (entirely or partially)
-changeable.  This is used when constructing reverse zones."
-  (dotimes (i 4 4)
-    (when (/= (ipaddr-byte mask i) 255)
-      (return (- 4 i)))))
 (defun default-rev-zone (base bytes)
+  "Return the default reverse-zone name for the given BASE address and number
+   of fixed leading BYTES."
   (join-strings #\. (collecting ()
 		      (loop for i from (- 3 bytes) downto 0
 			    do (collect (ipaddr-byte base i)))
@@ -532,7 +311,7 @@ changeable.  This is used when constructing reverse zones."
 
 (defun zone-name-from-net (net &optional bytes)
   "Given a NET, and maybe the BYTES to use, convert to the appropriate
-subdomain of in-addr.arpa."
+   subdomain of in-addr.arpa."
   (let ((ipn (net-get-as-ipnet net)))
     (with-ipnet (net mask) ipn
       (unless bytes
@@ -542,7 +321,7 @@ subdomain of in-addr.arpa."
 			       for i from (- 4 bytes) below 4
 			       collect (logand #xff (ash net (* -8 i))))
 			    (list "in-addr.arpa"))))))
-		      
+
 (defun zone-net-from-name (name)
   "Given a NAME in the in-addr.arpa space, convert it to an ipnet."
   (let* ((name (string-downcase (stringify name)))
@@ -570,54 +349,16 @@ subdomain of in-addr.arpa."
     (setf addr (ash addr (* 8 (- 4 n))))
     (make-ipnet addr (* 8 n))))
 
-(defun zone-reverse-records (records net list bytes dom)
-  "Construct a reverse zone given a forward zone's RECORDS list, the NET that
-the reverse zone is to serve, a LIST to collect the records into, how
-many BYTES of data need to end up in the zone, and the DOM-ain suffix."
-  (dolist (zr records)
-    (when (and (eq (zr-type zr) :a)
-	       (not (zr-defsubp zr))
-	       (ipaddr-networkp (zr-data zr) net))
-      (collect (make-zone-record
-		:name (string-downcase
-		       (join-strings
-			#\.
-			(collecting ()
-			  (dotimes (i bytes)
-			    (collect (logand #xff (ash (zr-data zr)
-						       (* -8 i)))))
-			  (collect dom))))
-		:type :ptr
-		:ttl (zr-ttl zr)
-		:data (zr-name zr))
-	       list))))
-
-(defun zone-reverse (data name list)
-  "Process a :reverse record's DATA, for a domain called NAME, and add the
-records to the LIST."
-  (destructuring-bind
-      (net &key bytes zones)
-      (listify data)
-    (setf net (zone-parse-net net name))
-    (dolist (z (or (listify zones)
-		   (hash-table-keys *zones*)))
-      (zone-reverse-records (zone-records (zone-find z))
-			    net
-			    list
-			    (or bytes
-				(ipnet-changeable-bytes (ipnet-mask net)))
-			    name))))
-
 (defun zone-parse-net (net name)
-  "Given a NET, and the NAME of a domain to guess from if NET is null,
-return the ipnet for the network."
+  "Given a NET, and the NAME of a domain to guess from if NET is null, return
+   the ipnet for the network."
   (if net
       (net-get-as-ipnet net)
       (zone-net-from-name name)))
 
 (defun zone-cidr-delg-default-name (ipn bytes)
   "Given a delegated net IPN and the parent's number of changing BYTES,
-return the default deletate zone prefix."
+   return the default deletate zone prefix."
   (with-ipnet (net mask) ipn
     (join-strings #\.
 		  (reverse
@@ -628,7 +369,7 @@ return the default deletate zone prefix."
 
 (defun zone-cidr-delegation (data name ttl list)
   "Given :cidr-delegation info DATA, for a record called NAME and the current
-TTL, write lots of CNAME records to LIST."
+   TTL, write lots of CNAME records to LIST."
   (destructuring-bind
       (net &key bytes)
       (listify (car data))
@@ -643,7 +384,7 @@ TTL, write lots of CNAME records to LIST."
 	(unless (ipnet-subnetp net tnet)
 	  (error "~A is not a subnet of ~A."
 		 (ipnet-pretty tnet)
-		 (ipnet-pretty net)))		 
+		 (ipnet-pretty net)))
 	(unless tdom
 	  (setf tdom
 		(join-strings #\.
@@ -665,8 +406,9 @@ TTL, write lots of CNAME records to LIST."
 		      :ttl ttl
 		      :data (join-strings #\. (list tail tdom)))
 		     list)))))))
-						  
-	      
+
+;;;--------------------------------------------------------------------------
+;;; Zone form parsing.
 
 (defun zone-parse-head (head)
   "Parse the HEAD of a zone form.  This has the form
@@ -674,8 +416,8 @@ TTL, write lots of CNAME records to LIST."
      (NAME &key :source :admin :refresh :retry
                 :expire :min-ttl :ttl :serial)
 
-though a singleton NAME needn't be a list.  Returns the default TTL and an
-soa structure representing the zone head."
+   though a singleton NAME needn't be a list.  Returns the default TTL and an
+   soa structure representing the zone head."
   (destructuring-bind
       (zname
        &key
@@ -699,38 +441,62 @@ soa structure representing the zone head."
 		      :min-ttl (timespec-seconds min-ttl)
 		      :serial serial))))
 
-(defun hash-table-keys (ht)
-  "Return a list of the keys in hashtable HT."
-  (collecting ()
-    (maphash (lambda (key val) (declare (ignore val)) (collect key)) ht)))
-
 (defmacro defzoneparse (types (name data list
 			       &key (zname (gensym "ZNAME"))
 			            (ttl (gensym "TTL"))
 				    (defsubp (gensym "DEFSUBP")))
 			&body body)
+  "Define a new zone record type (or TYPES -- a list of synonyms is
+   permitted).  The arguments are as follows:
+
+   NAME		The name of the record to be added.
+
+   DATA		The content of the record to be added (a single object,
+		unevaluated).
+
+   LIST		A function to add a record to the zone.  See below.
+
+   ZNAME	The name of the zone being constructed.
+
+   TTL		The TTL for this record.
+
+   DEFSUBP	Whether this is the default subdomain for this entry.
+
+   You get to choose your own names for these.  ZNAME, TTL and DEFSUBP are
+   optional: you don't have to accept them if you're not interested.
+
+   The LIST argument names a function to be bound in the body to add a new
+   low-level record to the zone.  It has the prototype
+
+     (LIST &key :name :type :data :ttl :defsubp)
+
+   Except for defsubp, these default to the above arguments (even if you
+   didn't accept the arguments)."
   (setf types (listify types))
   (let* ((type (car types))
 	 (func (intern (format nil "ZONE-PARSE/~:@(~A~)" type))))
-    (with-gensyms (col tname ttype tttl tdata tdefsubp i)
-      `(progn
-	 (dolist (,i ',types)
-	   (setf (get ,i 'zone-parse) ',func))
-	 (defun ,func (,name ,data ,ttl ,col ,zname ,defsubp)
-	   (declare (ignorable ,zname ,defsubp))
-	   (flet ((,list (&key ((:name ,tname) ,name)
-			       ((:type ,ttype) ,type)
-			       ((:data ,tdata) ,data)
-			       ((:ttl ,tttl) ,ttl)
-			       ((:defsubp ,tdefsubp) nil))
-		    (collect (make-zone-record :name ,tname
-					       :type ,ttype
-					       :data ,tdata
-					       :ttl ,tttl
-					       :defsubp ,tdefsubp)
-			     ,col)))
-	     ,@body))
-	 ',type))))
+    (with-parsed-body (body decls doc) body
+      (with-gensyms (col tname ttype tttl tdata tdefsubp i)
+	`(progn
+	   (dolist (,i ',types)
+	     (setf (get ,i 'zone-parse) ',func))
+	   (defun ,func (,name ,data ,ttl ,col ,zname ,defsubp)
+	     ,@doc
+	     ,@decls
+	     (declare (ignorable ,zname ,defsubp))
+	     (flet ((,list (&key ((:name ,tname) ,name)
+				 ((:type ,ttype) ,type)
+				 ((:data ,tdata) ,data)
+				 ((:ttl ,tttl) ,ttl)
+				 ((:defsubp ,tdefsubp) nil))
+		      (collect (make-zone-record :name ,tname
+						 :type ,ttype
+						 :data ,tdata
+						 :ttl ,tttl
+						 :defsubp ,tdefsubp)
+			       ,col)))
+	       ,@body))
+	   ',type)))))
 
 (defun zone-parse-records (zone records)
   (let ((zname (zone-name zone)))
@@ -758,18 +524,18 @@ soa structure representing the zone head."
 			    (zr-defsubp zr)))))
 	  (zone-process-records records
 				(zone-default-ttl zone)
-				#'parse-record ))
+				#'parse-record))
       (setf (zone-records zone) (nconc (zone-records zone) rec)))))
 
 (defun zone-parse (zf)
   "Parse a ZONE form.  The syntax of a zone form is as follows:
 
-ZONE-FORM:
-  ZONE-HEAD ZONE-RECORD*
+   ZONE-FORM:
+     ZONE-HEAD ZONE-RECORD*
 
-ZONE-RECORD:
-  ((NAME*) ZONE-RECORD*)
-| SYM ARGS"
+   ZONE-RECORD:
+     ((NAME*) ZONE-RECORD*)
+   | SYM ARGS"
   (multiple-value-bind (zname ttl soa) (zone-parse-head (car zf))
     (let ((zone (make-zone :name zname
 			   :default-ttl ttl
@@ -778,15 +544,43 @@ ZONE-RECORD:
       (zone-parse-records zone (cdr zf))
       zone)))
 
+(defun zone-create (zf)
+  "Zone construction function.  Given a zone form ZF, construct the zone and
+   add it to the table."
+  (let* ((zone (zone-parse zf))
+	 (name (zone-name zone)))
+    (setf (zone-find name) zone)
+    name))
+
+(defmacro defzone (soa &rest zf)
+  "Zone definition macro."
+  `(zone-create '(,soa ,@zf)))
+
+(defmacro defrevzone (head &rest zf)
+  "Define a reverse zone, with the correct name."
+  (destructuring-bind
+      (net &rest soa-args)
+      (listify head)
+    (let ((bytes nil))
+      (when (and soa-args (integerp (car soa-args)))
+	(setf bytes (pop soa-args)))
+      `(zone-create '((,(zone-name-from-net net bytes) ,@soa-args) ,@zf)))))
+
+;;;--------------------------------------------------------------------------
+;;; Zone record parsers.
+
 (defzoneparse :a (name data rec :defsubp defsubp)
   ":a IPADDR"
   (rec :data (parse-ipaddr data) :defsubp defsubp))
+
 (defzoneparse :ptr (name data rec :zname zname)
   ":ptr HOST"
   (rec :data (zone-parse-host data zname)))
+
 (defzoneparse :cname (name data rec :zname zname)
   ":cname HOST"
   (rec :data (zone-parse-host data zname)))
+
 (defzoneparse :mx (name data rec :zname zname)
   ":mx ((HOST :prio INT :ip IPADDR)*)"
   (dolist (mx (listify data))
@@ -796,6 +590,7 @@ ZONE-RECORD:
       (let ((host (zone-parse-host mxname zname)))
 	(when ip (rec :name host :type :a :data (parse-ipaddr ip)))
 	(rec :data (cons host prio))))))
+
 (defzoneparse :ns (name data rec :zname zname)
   ":ns ((HOST :ip IPADDR)*)"
   (dolist (ns (listify data))
@@ -805,12 +600,14 @@ ZONE-RECORD:
       (let ((host (zone-parse-host nsname zname)))
 	(when ip (rec :name host :type :a :data (parse-ipaddr ip)))
 	(rec :data host)))))
+
 (defzoneparse :alias (name data rec :zname zname)
   ":alias (LABEL*)"
   (dolist (a (listify data))
     (rec :name (zone-parse-host a zname)
 	 :type :cname
 	 :data name)))
+
 (defzoneparse :net (name data rec)
   ":net (NETWORK*)"
   (dolist (net (listify data))
@@ -824,7 +621,7 @@ ZONE-RECORD:
       (rec :name (zone-parse-host "broadcast" name)
 	   :type :a
 	   :data (ipnet-broadcast n)))))
-  
+
 (defzoneparse (:rev :reverse) (name data rec)
   ":reverse ((NET :bytes BYTES) ZONE*)"
   (setf data (listify data))
@@ -868,7 +665,7 @@ ZONE-RECORD:
 	(unless (ipnet-subnetp net tnet)
 	  (error "~A is not a subnet of ~A."
 		 (ipnet-pretty tnet)
-		 (ipnet-pretty net)))		 
+		 (ipnet-pretty net)))
 	(unless tdom
 	  (with-ipnet (net mask) tnet
 	    (setf tdom
@@ -895,24 +692,8 @@ ZONE-RECORD:
 		 :type :cname
 		 :data (format nil "~A.~A" tail tdom))))))))
 
-(defun iso-date (&optional time &key datep timep (sep #\ ))
-  "Construct a textual date or time in ISO format.  The TIME is the universal
-time to convert, which defaults to now; DATEP is whether to emit the date;
-TIMEP is whether to emit the time, and SEP (default is space) is how to
-separate the two."
-  (multiple-value-bind
-      (sec min hr day mon yr dow dstp tz)
-      (decode-universal-time (if (or (null time) (eq time :now))
-				 (get-universal-time)
-				 time))
-    (declare (ignore dow dstp tz))
-    (with-output-to-string (s)
-      (when datep
-	(format s "~4,'0D-~2,'0D-~2,'0D" yr mon day)
-	(when timep
-	  (write-char sep s)))
-      (when timep
-	(format s "~2,'0D:~2,'0D:~2,'0D" hr min sec)))))
+;;;--------------------------------------------------------------------------
+;;; Zone file output.
 
 (defun zone-write (zone &optional (stream *standard-output*))
   "Write a ZONE's records to STREAM."
@@ -945,8 +726,8 @@ separate the two."
 ;;; Zone file `~(~A~)'
 ;;;   (generated ~A)
 
-$ORIGIN ~@0*~(~A.~)
-$TTL ~@2*~D~2%"
+$ORIGIN ~0@*~(~A.~)
+$TTL ~2@*~D~2%"
 	    (zone-name zone)
 	    (iso-date :now :datep t :timep t)
 	    (zone-default-ttl zone))
@@ -985,30 +766,9 @@ $TTL ~@2*~D~2%"
 	 (printrec zr)
 	 (format stream "~S~%" (stringify (zr-data zr))))))))
 
-(defun zone-create (zf)
-  "Zone construction function.  Given a zone form ZF, construct the zone and
-add it to the table."
-  (let* ((zone (zone-parse zf))
-	 (name (zone-name zone)))
-    (setf (zone-find name) zone)
-    name))
-(defmacro defzone (soa &rest zf)
-  "Zone definition macro."
-  `(zone-create '(,soa ,@zf)))
-(defmacro defrevzone (head &rest zf)
-  "Define a reverse zone, with the correct name."
-  (destructuring-bind
-      (net &rest soa-args)
-      (listify head)
-    (let ((bytes nil))
-      (when (and soa-args (integerp (car soa-args)))
-	(setf bytes (pop soa-args)))
-      `(zone-create '((,(zone-name-from-net net bytes) ,@soa-args) ,@zf)))))
-		       
-
 (defun zone-save (zones)
   "Write the named ZONES to files.  If no zones are given, write all the
-zones."
+   zones."
   (unless zones
     (setf zones (hash-table-keys *zones*)))
   (safely (safe)