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1 | ;;; -*-lisp-*- |
2 | ;;; | |
9c44003b MW |
3 | ;;; Network (numbering) tools |
4 | ;;; | |
5 | ;;; (c) 2006 Straylight/Edgeware | |
6 | ;;; | |
7 | ||
8 | ;;;----- Licensing notice --------------------------------------------------- | |
9 | ;;; | |
10 | ;;; This program is free software; you can redistribute it and/or modify | |
11 | ;;; it under the terms of the GNU General Public License as published by | |
12 | ;;; the Free Software Foundation; either version 2 of the License, or | |
13 | ;;; (at your option) any later version. | |
7fff3797 | 14 | ;;; |
9c44003b MW |
15 | ;;; This program is distributed in the hope that it will be useful, |
16 | ;;; but WITHOUT ANY WARRANTY; without even the implied warranty of | |
17 | ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
18 | ;;; GNU General Public License for more details. | |
7fff3797 | 19 | ;;; |
9c44003b MW |
20 | ;;; You should have received a copy of the GNU General Public License |
21 | ;;; along with this program; if not, write to the Free Software Foundation, | |
22 | ;;; Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
23 | ||
9c44003b MW |
24 | (in-package #:net) |
25 | ||
26 | ;;;-------------------------------------------------------------------------- | |
32ebbe9b | 27 | ;;; Various random utilities. |
9c44003b | 28 | |
32ebbe9b | 29 | (declaim (inline mask)) |
9c44003b MW |
30 | (defun mask (n) |
31 | "Return 2^N - 1: i.e., a mask of N set bits." | |
32 | (1- (ash 1 n))) | |
33 | ||
32ebbe9b MW |
34 | (defun find-first-bit-transition |
35 | (mask &optional (low 0) (high (integer-length mask))) | |
36 | "Find the first (lowest bit-position) transition in MASK within the bounds. | |
9c44003b | 37 | |
32ebbe9b MW |
38 | The LOW bound is inclusive; the high bound is exclusive. A transition is |
39 | a change from zero to one, or vice-versa. The return value is the | |
40 | upper (exclusive) bound on the initial run, and the lower (inclusive) | |
41 | bound on the new run. | |
9c44003b | 42 | |
32ebbe9b MW |
43 | If there is no transition within the bounds, then return HIGH." |
44 | ||
45 | ;; Arrange that the initial run is ones. | |
46 | (unless (logbitp low mask) (setf mask (lognot mask))) | |
47 | ||
48 | ;; Now, note that MASK + 2^LOW is identical to MASK in all bit positions | |
49 | ;; except for (a) the run of one bits starting at LOW, and (b) the zero bit | |
50 | ;; just above it. So MASK xor (MASK + 2^LOW) is zero except for these | |
51 | ;; bits; so all we need now is to find the position of its most significant | |
52 | ;; set bit. | |
53 | (let ((pos (1- (integer-length (logxor mask (+ mask (ash 1 low))))))) | |
54 | (if (<= low pos high) pos high))) | |
9c44003b MW |
55 | |
56 | (defun count-low-zero-bits (n) | |
57 | "Return the number of low-order zero bits in the integer N." | |
32ebbe9b MW |
58 | (cond ((zerop n) nil) |
59 | ((oddp n) 0) | |
60 | (t (find-first-bit-transition n)))) | |
61 | ||
62 | (declaim (inline round-down)) | |
63 | (defun round-down (n step) | |
64 | "Return the largest multiple of STEP not greater than N." | |
65 | (* step (floor n step))) | |
66 | ||
67 | (declaim (inline round-up)) | |
68 | (defun round-up (n step) | |
69 | "Return the smallest multiple of STEP not less than N." | |
70 | (* step (ceiling n step))) | |
71 | ||
72 | (defgeneric extract-class-name (object) | |
73 | (:documentation "Turn OBJECT into a class name.") | |
74 | (:method ((instance standard-object)) | |
75 | (extract-class-name (class-of instance))) | |
76 | (:method ((class standard-class)) | |
77 | (class-name class)) | |
78 | (:method ((name symbol)) | |
79 | name)) | |
80 | ||
81 | (defclass savable-object () | |
82 | ()) | |
83 | (defmethod make-load-form ((object savable-object) &optional environment) | |
84 | (make-load-form-saving-slots object :environment environment)) | |
85 | ||
86 | ;;;-------------------------------------------------------------------------- | |
87 | ;;; Parsing primitives for addresses. | |
88 | ||
89 | (defun parse-partial-address | |
90 | (str | |
91 | &key (start 0) (end nil) (delim #\.) | |
92 | (width 8) (radix 10) (min 1) (max 32) (shiftp t) | |
93 | (what "address")) | |
94 | "Parse a partial address from STR, which should be a sequence of integers | |
95 | in the given RADIX, separated by the DELIM character, with each integer | |
96 | N_i in the interval 0 <= N_i < 2^WIDTH. If the sequence is N_1, N_2, ..., | |
97 | N_k, then the basic partial address BPA is the sum | |
98 | ||
99 | SUM_{1<=i<=k} 2^{WIDTH (k-i)} N_i | |
100 | ||
101 | If SHIFTP is true (the default) then let OFFSET be the smallest multiple | |
102 | of WIDTH not less than MAX - k WIDTH; otherwise, let OFFSET be zero. The | |
103 | partial address PA is BPA 2^SHIFT. | |
104 | ||
105 | The return values are: PA, OFFSET, k WIDTH + OFFSET; i.e., the partial | |
106 | address, and (inclusive) lower and (exclusive) upper bounds on the bits | |
107 | specified by STR." | |
108 | ||
109 | (setf-default end (length str)) | |
110 | (let ((addr 0) (nbits 0) (limit (ash 1 width))) | |
111 | (when (< start end) | |
112 | (loop | |
113 | (when (>= nbits max) | |
114 | (error "Too many elements in ~A" what)) | |
115 | (let* ((pos (position delim str :start start :end end)) | |
116 | (w (parse-integer str :radix radix | |
117 | :start start :end (or pos end)))) | |
118 | (unless (and (<= 0 w) (< w limit)) | |
119 | (error "Element out of range in ~A" what)) | |
120 | (setf addr (logior (ash addr width) w)) | |
121 | (incf nbits width) | |
122 | (unless pos (return)) | |
123 | (setf start (1+ pos))))) | |
124 | (when (< nbits min) | |
125 | (error "Not enough elements in ~A" what)) | |
126 | (if shiftp | |
127 | (let* ((top (round-up max width)) | |
128 | (shift (- top nbits))) | |
129 | (values (ash addr shift) shift top)) | |
130 | (values addr 0 nbits)))) | |
9c44003b MW |
131 | |
132 | ;;;-------------------------------------------------------------------------- | |
32ebbe9b MW |
133 | ;;; Simple messing about with IP addresses. |
134 | ||
135 | (export 'ipaddr) | |
136 | (export 'ipaddr-addr) | |
137 | (defclass ipaddr (savable-object) | |
138 | () | |
139 | (:documentation | |
140 | "Base class for IP addresses.")) | |
141 | ||
142 | (export 'ipaddr-family) | |
6a26c716 MW |
143 | (defgeneric ipaddr-family (addr) |
144 | (:documentation "Return the address family of ADDR, as a keyword.")) | |
32ebbe9b MW |
145 | |
146 | (export 'family-addrclass) | |
147 | (defgeneric family-addrclass (family) | |
6a26c716 | 148 | (:documentation "Convert the keyword FAMILY into an `ipaddr' subclass.") |
32ebbe9b MW |
149 | (:method ((af symbol)) nil)) |
150 | ||
151 | (export 'ipaddr-width) | |
152 | (defgeneric ipaddr-width (class) | |
6a26c716 MW |
153 | (:documentation "Return the width, in bits, of addresses from CLASS. |
154 | ||
155 | Alternatively, the CLASS may be given as an example object.") | |
32ebbe9b MW |
156 | (:method ((object t)) (ipaddr-width (extract-class-name object)))) |
157 | ||
158 | (export 'ipaddr-comparable-p) | |
159 | (defgeneric ipaddr-comparable-p (addr-a addr-b) | |
6a26c716 | 160 | (:documentation "Is it meaningful to compare ADDR-A and ADDR-B?") |
32ebbe9b MW |
161 | (:method ((addr-a ipaddr) (addr-b ipaddr)) |
162 | (eq (class-of addr-a) (class-of addr-b)))) | |
163 | ||
164 | (defun guess-address-class (str &key (start 0) (end nil)) | |
6a26c716 MW |
165 | "Return a class name for the address in (the given substring of) STR. |
166 | ||
167 | This ought to be an extension point for additional address families, but | |
168 | it isn't at the moment." | |
a2267e14 MW |
169 | (cond ((position #\: str :start start :end end) 'ip6addr) |
170 | (t 'ip4addr))) | |
32ebbe9b MW |
171 | |
172 | (defgeneric parse-partial-ipaddr (class str &key start end min max) | |
6a26c716 MW |
173 | (:documentation |
174 | "Parse (a substring of) STR into a partial address of the given CLASS. | |
175 | ||
176 | Returns three values: the parsed address fragment, as an integer; and the | |
177 | low and high bit positions covered by the response. | |
178 | ||
179 | The CLASS may instead be an example object of the required class. The MIN | |
180 | and MAX arguments bound the number of bits acceptable in the response; the | |
181 | result is shifted so that the most significant component of the returned | |
182 | address is in the same component as bit position MAX.") | |
32ebbe9b MW |
183 | (:method ((object t) str &rest keywords) |
184 | (apply #'parse-partial-ipaddr (extract-class-name object) str keywords))) | |
9c44003b | 185 | |
e1528fd6 | 186 | (export 'string-ipaddr) |
9c44003b | 187 | (defun string-ipaddr (str &key (start 0) (end nil)) |
32ebbe9b | 188 | "Parse STR into an address; guess what kind is intended by the user. |
f4e0c48f MW |
189 | |
190 | STR may be anything at all: it's converted as if by `stringify'. | |
191 | The START and END arguments may be used to parse out a substring." | |
9c44003b | 192 | (setf str (stringify str)) |
32ebbe9b MW |
193 | (let* ((class (guess-address-class str :start start :end end)) |
194 | (width (ipaddr-width class))) | |
195 | (make-instance class :addr | |
196 | (parse-partial-ipaddr class str | |
197 | :start start :end end | |
198 | :min width :max width)))) | |
199 | ||
200 | (export 'integer-ipaddr) | |
201 | (defgeneric integer-ipaddr (int like) | |
202 | (:documentation "Convert INT into an address of type indicated by LIKE. | |
203 | ||
204 | Specifically, if LIKE is an address object, then use its type; if it's | |
205 | a class, then use it directly; if it's a symbol, then use the class it | |
206 | names.") | |
207 | (:method (int (like t)) (integer-ipaddr int (class-of like))) | |
208 | (:method (int (like symbol)) | |
209 | (make-instance (or (family-addrclass like) like) :addr int)) | |
210 | (:method (int (like standard-class)) (make-instance like :addr int))) | |
9c44003b | 211 | |
e1528fd6 | 212 | (export 'ipaddr-string) |
32ebbe9b | 213 | (defgeneric ipaddr-string (ip) |
6a26c716 | 214 | (:documentation "Transform the address IP into a numeric textual form.")) |
32ebbe9b MW |
215 | |
216 | (defmethod print-object ((addr ipaddr) stream) | |
217 | (print-unreadable-object (addr stream :type t) | |
218 | (write-string (ipaddr-string addr) stream))) | |
9c44003b | 219 | |
e1528fd6 | 220 | (export 'ipaddrp) |
9c44003b MW |
221 | (defun ipaddrp (ip) |
222 | "Answer true if IP is a valid IP address in integer form." | |
223 | (typep ip 'ipaddr)) | |
224 | ||
32ebbe9b MW |
225 | (defun ipaddr (ip &optional like) |
226 | "Convert IP to an IP address, of type similar to LIKE. | |
f4e0c48f | 227 | |
32ebbe9b MW |
228 | If it's an IP address, just return it unchanged; If it's an integer, |
229 | capture it; otherwise convert by `string-ipaddr'." | |
9c44003b MW |
230 | (typecase ip |
231 | (ipaddr ip) | |
32ebbe9b | 232 | (integer (integer-ipaddr ip like)) |
9c44003b MW |
233 | (t (string-ipaddr ip)))) |
234 | ||
32ebbe9b MW |
235 | (export 'ipaddr-rrtype) |
236 | (defgeneric ipaddr-rrtype (addr) | |
237 | (:documentation "Return the proper resource record type for ADDR.")) | |
238 | ||
9c44003b MW |
239 | ;;;-------------------------------------------------------------------------- |
240 | ;;; Netmasks. | |
241 | ||
e1528fd6 | 242 | (export 'integer-netmask) |
32ebbe9b MW |
243 | (defun integer-netmask (n i) |
244 | "Given an integer I, return an N-bit netmask with its I top bits set." | |
245 | (- (ash 1 n) (ash 1 (- n i)))) | |
9c44003b | 246 | |
e1528fd6 | 247 | (export 'ipmask-cidl-slash) |
32ebbe9b | 248 | (defun ipmask-cidl-slash (width mask) |
f4e0c48f MW |
249 | "Given a netmask MASK, try to compute a prefix length. |
250 | ||
32ebbe9b MW |
251 | Return an integer N such that (integer-netmask WIDTH N) = MASK, or nil if |
252 | this is impossible." | |
253 | (let* ((low (logxor mask (mask width))) | |
254 | (bits (integer-length low))) | |
255 | (and (= low (mask bits)) (- width bits)))) | |
256 | ||
257 | (export 'ipmask) | |
258 | (defgeneric ipmask (addr mask) | |
259 | (:documentation "Convert MASK into a suitable netmask for ADDR.") | |
260 | (:method ((addr ipaddr) (mask null)) | |
261 | (mask (ipaddr-width addr))) | |
262 | (:method ((addr ipaddr) (mask integer)) | |
263 | (let ((w (ipaddr-width addr))) | |
264 | (if (<= 0 mask w) | |
265 | (integer-netmask w mask) | |
b496b60f | 266 | (error "Prefix length out of range."))))) |
32ebbe9b MW |
267 | |
268 | (export 'mask-ipaddr) | |
269 | (defun mask-ipaddr (addr mask) | |
270 | "Apply the MASK to the ADDR, returning the base address." | |
271 | (integer-ipaddr (logand mask (ipaddr-addr addr)) addr)) | |
9c44003b MW |
272 | |
273 | ;;;-------------------------------------------------------------------------- | |
274 | ;;; Networks: pairing an address and netmask. | |
275 | ||
e1528fd6 | 276 | (export 'ipnet) |
32ebbe9b MW |
277 | (export 'ipnet-net) |
278 | (export 'ipnet-mask) | |
279 | (defclass ipnet (savable-object) | |
280 | () | |
281 | (:documentation "Base class for IP networks.")) | |
9c44003b | 282 | |
32ebbe9b MW |
283 | (export 'ipnet-family) |
284 | (defgeneric ipnet-family (ipn) | |
6a26c716 | 285 | (:documentation "Return the address family of IPN, as a keyword.") |
32ebbe9b | 286 | (:method ((ipn ipnet)) (ipaddr-family (ipnet-net ipn)))) |
9c44003b | 287 | |
32ebbe9b MW |
288 | (export 'ipnet-addr) |
289 | (defun ipnet-addr (ipn) | |
290 | "Return the base network address of IPN as a raw integer." | |
291 | (ipaddr-addr (ipnet-net ipn))) | |
9c44003b | 292 | |
32ebbe9b MW |
293 | (export 'ipaddr-ipnet) |
294 | (defgeneric ipaddr-ipnet (addr mask) | |
295 | (:documentation "Construct an `ipnet' object given a base ADDR and MASK.")) | |
296 | ||
297 | (export 'make-ipnet) | |
298 | (defun make-ipnet (net mask) | |
6a26c716 MW |
299 | "Construct an IP-network object given the NET and MASK. |
300 | ||
301 | These are transformed as though by `ipaddr' and `ipmask'." | |
32ebbe9b MW |
302 | (let* ((net (ipaddr net)) |
303 | (mask (ipmask net mask))) | |
304 | (ipaddr-ipnet (mask-ipaddr net mask) mask))) | |
9c44003b | 305 | |
e1528fd6 | 306 | (export 'with-ipnet) |
32ebbe9b | 307 | (defmacro with-ipnet ((net addr mask) ipn &body body) |
f4e0c48f MW |
308 | "Evaluate the BODY with components of IPN in scope. |
309 | ||
32ebbe9b MW |
310 | The NET is bound to the underlying network base address, as an `ipaddr'; |
311 | ADDR is bound to the integer value of this address; and MASK is bound to | |
312 | the netmask, again as an integer. Any (or all) of these may be nil if not | |
313 | wanted." | |
9c44003b MW |
314 | (with-gensyms tmp |
315 | `(let ((,tmp ,ipn)) | |
316 | (let (,@(and net `((,net (ipnet-net ,tmp)))) | |
32ebbe9b | 317 | ,@(and addr `((,addr (ipnet-addr ,tmp)))) |
9c44003b MW |
318 | ,@(and mask `((,mask (ipnet-mask ,tmp))))) |
319 | ,@body)))) | |
320 | ||
32ebbe9b MW |
321 | (export 'ipnet-width) |
322 | (defun ipnet-width (ipn) | |
323 | "Return the underlying bit width of the addressing system." | |
324 | (ipaddr-width (ipnet-net ipn))) | |
9c44003b | 325 | |
e1528fd6 | 326 | (export 'ipnet-string) |
9c44003b MW |
327 | (defun ipnet-string (ipn) |
328 | "Convert IPN to a string." | |
32ebbe9b | 329 | (with-ipnet (net nil mask) ipn |
9c44003b MW |
330 | (format nil "~A/~A" |
331 | (ipaddr-string net) | |
32ebbe9b MW |
332 | (or (ipmask-cidl-slash (ipnet-width ipn) mask) |
333 | (ipaddr-string (make-instance (class-of net) :addr mask)))))) | |
334 | ||
335 | (defmethod print-object ((ipn ipnet) stream) | |
336 | (print-unreadable-object (ipn stream :type t) | |
337 | (write-string (ipnet-string ipn) stream))) | |
338 | ||
6343e7bf | 339 | (defun parse-subnet (class width max str &key (start 0) (end nil) (slashp t)) |
6a26c716 MW |
340 | "Parse a subnet description from (a substring of) STR. |
341 | ||
342 | Suppose we have a parent network, with a prefix length of MAX. The WIDTH | |
343 | gives the overall length of addresses of the appropriate class, i.e., | |
344 | (ipaddr-width WIDTH), but in fact callers have already computed this for | |
345 | their own reasons. | |
346 | ||
347 | Parse (the designated substring of) STR to construct the base address of a | |
348 | subnet. The string should have the form BASE/MASK, where the MASK is | |
349 | either a literal bitmask (in the usual syntax for addresses) or an integer | |
350 | prefix length. An explicit prefix length is expected to cover the entire | |
351 | address including the parent prefix: an error is signalled if the prefix | |
352 | isn't long enough to cover any of the subnet. A mask is parsed relative | |
353 | to the end of the parent address, just as the subnet base address is. | |
354 | ||
355 | Returns the relative base address and mask as two integer values." | |
356 | ||
32ebbe9b | 357 | (setf-default end (length str)) |
6343e7bf | 358 | (let ((sl (and slashp (position #\/ str :start start :end end)))) |
32ebbe9b MW |
359 | (multiple-value-bind (addr lo hi) |
360 | (parse-partial-ipaddr class str :max max | |
361 | :start start :end (or sl end)) | |
362 | (let* ((present (integer-netmask hi (- hi lo))) | |
363 | (mask (cond ((not sl) | |
364 | present) | |
365 | ((every #'digit-char-p (subseq str (1+ sl) end)) | |
366 | (let ((length (parse-integer str | |
367 | :start (1+ sl) | |
368 | :end end))) | |
369 | (unless (>= length (- width max)) | |
370 | (error "Mask doesn't reach subnet boundary")) | |
371 | (integer-netmask max (- length (- width max))))) | |
372 | (t | |
373 | (parse-partial-ipaddr class str :max max | |
374 | :start (1+ sl) :end end))))) | |
375 | (unless (zerop (logandc2 mask present)) | |
376 | (error "Mask selects bits not present in base address")) | |
377 | (values addr mask))))) | |
378 | ||
6343e7bf MW |
379 | (defun check-subipnet (base-ipn sub-addr sub-mask) |
380 | "Verify that SUB-NET/SUB-MASK is an appropriate subnet of BASE-IPN. | |
32ebbe9b | 381 | |
6343e7bf MW |
382 | The BASE-IPN is an `ipnet'; SUB-ADDR and SUB-MASK are plain integers. If |
383 | the subnet is invalid (i.e., the subnet disagrees with its putative parent | |
384 | over some of the fixed address bits) then an error is signalled; otherwise | |
385 | return the combined base address (as an `ipaddr') and mask (as an | |
386 | integer)." | |
32ebbe9b | 387 | (with-ipnet (base-net base-addr base-mask) base-ipn |
6343e7bf | 388 | (let* ((common (logand base-mask sub-mask)) |
32ebbe9b MW |
389 | (base-overlap (logand base-addr common)) |
390 | (sub-overlap (logand sub-addr common)) | |
391 | (full-mask (logior base-mask sub-mask))) | |
6343e7bf | 392 | (unless (or (zerop sub-overlap) (= sub-overlap base-overlap)) |
32ebbe9b | 393 | (error "Subnet doesn't match base network")) |
6343e7bf MW |
394 | (values (integer-ipaddr (logand full-mask (logior base-addr sub-addr)) |
395 | base-net) | |
396 | full-mask)))) | |
32ebbe9b MW |
397 | |
398 | (export 'string-ipnet) | |
399 | (defun string-ipnet (str &key (start 0) (end nil)) | |
6a26c716 MW |
400 | "Parse an IP network description from the string STR. |
401 | ||
402 | A network description has the form ADDRESS/MASK, where the ADDRESS is a | |
403 | base address in numeric form, and the MASK is either a netmask in the same | |
404 | form, or an integer prefix length." | |
32ebbe9b MW |
405 | (setf str (stringify str)) |
406 | (setf-default end (length str)) | |
407 | (let ((addr-class (guess-address-class str :start start :end end))) | |
408 | (multiple-value-bind (addr mask) | |
409 | (let ((width (ipaddr-width addr-class))) | |
410 | (parse-subnet addr-class width width str | |
411 | :start start :end end)) | |
412 | (make-ipnet (make-instance addr-class :addr addr) | |
413 | (make-instance addr-class :addr mask))))) | |
414 | ||
6343e7bf MW |
415 | (defun parse-subipnet (ipn str &key (start 0) (end nil) (slashp t)) |
416 | "Parse STR as a subnet of IPN. | |
417 | ||
6a26c716 MW |
418 | This is mostly a convenience interface over `parse-subnet'; we compute |
419 | various of the parameters from IPN rather than requiring them to be passed | |
420 | in explicitly. | |
421 | ||
422 | Returns two values: the combined base address, as an `ipnaddr' and | |
423 | combined mask, as an integer." | |
424 | ||
32ebbe9b MW |
425 | (let* ((addr-class (extract-class-name (ipnet-net ipn))) |
426 | (width (ipaddr-width addr-class)) | |
427 | (max (- width | |
428 | (or (ipmask-cidl-slash width (ipnet-mask ipn)) | |
429 | (error "Base network has complex netmask"))))) | |
430 | (multiple-value-bind (addr mask) | |
6343e7bf MW |
431 | (parse-subnet addr-class width max (stringify str) |
432 | :start start :end end :slashp slashp) | |
433 | (check-subipnet ipn addr mask)))) | |
434 | ||
435 | (export 'string-subipnet) | |
436 | (defun string-subipnet (ipn str &key (start 0) (end nil)) | |
6a26c716 MW |
437 | "Parse an IP subnet from a parent net IPN and a suffix string STR. |
438 | ||
439 | The (substring of) STR is expected to have the form ADDRESS/MASK, where | |
440 | ADDRESS is a relative subnet base address, and MASK is either a relative | |
441 | subnet mask or a (full) prefix length. Returns the resulting ipnet. If | |
442 | the relative base address overlaps with the existing subnet (because the | |
443 | base network's prefix length doesn't cover a whole number of components), | |
444 | then the subnet base must either agree in the overlapping portion with the | |
445 | parent base address or be zero. | |
446 | ||
447 | For example, if IPN is the network 172.29.0.0/16, then `199/24' or | |
448 | `199/255' both designate the subnet 172.29.199.0/24. Similarly, starting | |
449 | from 2001:ba8:1d9:8000::/52, then `8042/ffff' and `42/64' both designate | |
450 | the network 2001:ba8:1d9:8042::/64." | |
451 | ||
6343e7bf MW |
452 | (multiple-value-bind (addr mask) |
453 | (parse-subipnet ipn str :start start :end end) | |
454 | (ipaddr-ipnet addr mask))) | |
32ebbe9b MW |
455 | |
456 | (defun ipnet (net) | |
457 | "Construct an IP-network object from the given argument. | |
458 | ||
459 | A number of forms are acceptable: | |
460 | ||
461 | * ADDR -- a single address, equivalent to (ADDR . N). | |
462 | * (NET . MASK|nil) -- a single-object representation. | |
463 | * IPNET -- return an equivalent (`equal', not necessarily `eql') | |
464 | version." | |
465 | (typecase net | |
466 | (ipnet net) | |
467 | ((or string symbol) (string-ipnet net)) | |
468 | (t (apply #'make-ipnet (pairify net nil))))) | |
9c44003b | 469 | |
e1528fd6 | 470 | (export 'ipnet-broadcast) |
32ebbe9b MW |
471 | (defgeneric ipnet-broadcast (ipn) |
472 | (:documentation "Return the broadcast address for the network IPN. | |
473 | ||
474 | Returns nil if there isn't one.")) | |
9c44003b | 475 | |
e1528fd6 | 476 | (export 'ipnet-hosts) |
9c44003b MW |
477 | (defun ipnet-hosts (ipn) |
478 | "Return the number of available addresses in network IPN." | |
32ebbe9b MW |
479 | (ash 1 (- (ipnet-width ipn) (logcount (ipnet-mask ipn))))) |
480 | ||
481 | (defstruct host-map | |
482 | "An internal object used by `ipnet-index-host' and `ipnet-host-index'. | |
483 | ||
484 | Our objective is to be able to convert between flat host indices and a | |
485 | possibly crazy non-flat host space. We record the underlying IPNET for | |
486 | convenience, and a list of byte-specifications for the runs of zero bits | |
487 | in the netmask, in ascending order." | |
488 | ipnet | |
489 | bytes) | |
490 | ||
491 | (export 'ipnet-host-map) | |
492 | (defun ipnet-host-map (ipn) | |
493 | "Work out how to enumerate the variable portion of IPN. | |
494 | ||
495 | Returns an object which can be passed to `ipnet-index-host' and | |
496 | `ipnet-host-index'." | |
497 | (let* ((mask (ipnet-mask ipn)) (bytes nil) (i 0) | |
498 | (len (integer-length mask)) (width (ipnet-width ipn))) | |
499 | (when (logbitp i mask) (setf i (find-first-bit-transition mask i))) | |
500 | (loop | |
501 | (unless (< i len) (return)) | |
502 | (let ((next (find-first-bit-transition mask i width))) | |
503 | (push (byte (- next i) i) bytes) | |
504 | (setf i (find-first-bit-transition mask next width)))) | |
505 | (when (< len width) (push (byte (- width len) len) bytes)) | |
506 | (make-host-map :ipnet ipn :bytes (nreverse bytes)))) | |
507 | ||
508 | (export 'ipnet-index-host) | |
509 | (defun ipnet-index-host (map host) | |
510 | "Convert a HOST index to its address." | |
511 | (let* ((ipn (host-map-ipnet map)) | |
512 | (addr (logand (ipnet-addr ipn) (ipnet-mask ipn)))) | |
513 | (dolist (byte (host-map-bytes map)) | |
514 | (setf (ldb byte addr) host | |
515 | host (ash host (- (byte-size byte))))) | |
516 | (unless (zerop host) | |
517 | (error "Host index out of range.")) | |
518 | (integer-ipaddr addr (ipnet-net ipn)))) | |
519 | ||
520 | (export 'ipnet-host-index) | |
521 | (defun ipnet-host-index (map addr) | |
522 | "Convert an ADDR into a host index." | |
523 | (let ((addr (ipaddr-addr addr)) | |
524 | (host 0) (offset 0)) | |
525 | (dolist (byte (host-map-bytes map)) | |
526 | (setf host (logior host | |
527 | (ash (ldb byte addr) offset)) | |
528 | offset (+ offset (byte-size byte)))) | |
529 | host)) | |
530 | ||
531 | (export 'ipnet-index-bounds) | |
532 | (defun ipnet-index-bounds (map start end) | |
533 | "Return host-index bounds corresponding to the given bit-position bounds." | |
534 | (flet ((hack (frob-map good-byte tweak-addr) | |
535 | (dolist (byte (funcall frob-map (host-map-bytes map))) | |
536 | (let* ((low (byte-position byte)) | |
537 | (high (+ low (byte-size byte))) | |
538 | (good (funcall good-byte low high))) | |
539 | (when good | |
540 | (return-from hack | |
541 | (ipnet-host-index map | |
542 | (ipaddr (funcall tweak-addr | |
543 | (ash 1 good)) | |
544 | (ipnet-net | |
545 | (host-map-ipnet map)))))))) | |
546 | (error "No variable bits in range."))) | |
547 | (values (hack #'identity | |
548 | (lambda (low high) | |
549 | (and (< start high) (max start low))) | |
550 | #'identity) | |
551 | (hack #'reverse | |
552 | (lambda (low high) | |
553 | (and (>= end low) (min end high))) | |
554 | #'1-)))) | |
9c44003b | 555 | |
e1528fd6 | 556 | (export 'ipnet-host) |
9c44003b | 557 | (defun ipnet-host (ipn host) |
f4e0c48f MW |
558 | "Return the address of the given HOST in network IPN. |
559 | ||
88867b1a MW |
560 | The HOST may be a an integer index into the network (this works even with |
561 | a non-contiguous netmask) or a string or symbolic suffix (as for | |
562 | `string-subnet')." | |
563 | (etypecase host | |
564 | (integer | |
565 | (ipnet-index-host (ipnet-host-map ipn) host)) | |
566 | ((or symbol string) | |
567 | (multiple-value-bind (addr mask) | |
568 | (parse-subipnet ipn host :slashp nil) | |
569 | (unless (= mask (mask (ipaddr-width addr))) | |
570 | (error "Host address incomplete")) | |
571 | addr)))) | |
9c44003b | 572 | |
e1528fd6 | 573 | (export 'ipaddr-networkp) |
9c44003b | 574 | (defun ipaddr-networkp (ip ipn) |
32ebbe9b MW |
575 | "Returns true if numeric address IP is within network IPN." |
576 | (with-ipnet (nil addr mask) ipn | |
577 | (= addr (logand ip mask)))) | |
9c44003b | 578 | |
e1528fd6 | 579 | (export 'ipnet-subnetp) |
9c44003b MW |
580 | (defun ipnet-subnetp (ipn subn) |
581 | "Returns true if SUBN is a (non-strict) subnet of IPN." | |
32ebbe9b MW |
582 | (with-ipnet (net addr mask) ipn |
583 | (with-ipnet (subnet subaddr submask) subn | |
584 | (and (ipaddr-comparable-p net subnet) | |
585 | (= addr (logand subaddr mask)) | |
9c44003b MW |
586 | (= submask (logior mask submask)))))) |
587 | ||
32ebbe9b MW |
588 | (export 'ipnet-overlapp) |
589 | (defun ipnet-overlapp (ipn-a ipn-b) | |
590 | "Returns true if IPN-A and IPN-B have any addresses in common." | |
591 | (with-ipnet (net-a addr-a mask-a) ipn-a | |
592 | (with-ipnet (net-b addr-b mask-b) ipn-b | |
593 | ||
594 | ;; In the case of an overlap, we explicitly construct a common | |
595 | ;; address. If this fails, we know that the networks don't overlap | |
596 | ;; after all. | |
597 | (flet ((narrow (addr-a mask-a addr-b mask-b) | |
598 | ;; Narrow network A towards B, by setting bits in A's base | |
599 | ;; address towards which A is indifferent, but B is not; | |
600 | ;; return the resulting base address. This address is still | |
601 | ;; within network A, since we only set bits to which A is | |
602 | ;; indifferent. | |
603 | (logior addr-a (logand addr-b (logandc2 mask-a mask-b))))) | |
604 | ||
605 | (and (ipaddr-comparable-p net-a net-b) | |
606 | (= (narrow addr-a mask-a addr-b mask-b) | |
607 | (narrow addr-b mask-b addr-a mask-a))))))) | |
608 | ||
609 | (export 'ipnet-changeable-bits) | |
610 | (defun ipnet-changeable-bits (width mask) | |
611 | "Work out the number of changeable bits in a network, given its MASK. | |
612 | ||
613 | This is a conservative estimate in the case of noncontiguous masks. The | |
614 | WIDTH is the total width of an address." | |
615 | ||
616 | ;; We bisect the address. If the low-order bits are changeable then we | |
617 | ;; recurse on them; otherwise we look at the high-order bits. A mask M of | |
618 | ;; width W is changeable if it's not all-ones, i.e., if M /= 2^W. If the | |
619 | ;; top half is changeable then we don't need to look at the bottom half. | |
620 | (labels ((recurse (width mask offset) | |
621 | (if (= width 1) | |
622 | (if (zerop mask) (1+ offset) offset) | |
623 | (let* ((lowwidth (floor width 2)) | |
624 | (highwidth (- width lowwidth)) | |
625 | (highmask (ash mask (- lowwidth)))) | |
626 | (if (logbitp highwidth (1+ highmask)) | |
627 | (recurse lowwidth | |
628 | (logand mask (mask lowwidth)) | |
629 | offset) | |
630 | (recurse highwidth highmask (+ offset lowwidth))))))) | |
631 | (recurse width mask 0))) | |
9c44003b MW |
632 | |
633 | ;;;-------------------------------------------------------------------------- | |
32ebbe9b MW |
634 | ;;; Reverse lookups. |
635 | ||
636 | (export 'reverse-domain-component-width) | |
637 | (defgeneric reverse-domain-component-width (ipaddr) | |
638 | (:documentation "Return the component width for splitting IPADDR.")) | |
639 | ||
640 | (export 'reverse-domain-component-radix) | |
641 | (defgeneric reverse-domain-radix (ipaddr) | |
642 | (:documentation "Return the radix for representing IPADDR components.")) | |
643 | ||
644 | (export 'reverse-domain-component-suffix) | |
645 | (defgeneric reverse-domain-suffix (ipaddr) | |
646 | (:documentation "Return the reverse-lookup domain suffix for IPADDR.")) | |
647 | ||
648 | (export 'reverse-domain-fragment) | |
649 | (defgeneric reverse-domain-fragment (ipaddr start end &key partialp) | |
650 | (:documentation | |
651 | "Return a portion of an IPADDR's reverse-resolution domain name. | |
652 | ||
653 | Specifically, return the portion of the name which covers the bits of an | |
654 | IPADDR between bits START (inclusive) and END (exclusive). Address | |
655 | components which are only partially within the given bounds are included | |
656 | unless PARTIALP is nil.") | |
657 | (:method ((ipaddr ipaddr) start end &key (partialp t)) | |
658 | ||
659 | (let ((addr (ipaddr-addr ipaddr)) | |
660 | (comp-width (reverse-domain-component-width ipaddr)) | |
661 | (radix (reverse-domain-radix ipaddr))) | |
662 | ||
663 | (with-output-to-string (out) | |
664 | (do ((i (funcall (if partialp #'round-down #'round-up) | |
665 | start comp-width) | |
666 | (+ i comp-width)) | |
667 | (limit (funcall (if partialp #'round-up #'round-down) | |
668 | end comp-width)) | |
669 | (sep nil t)) | |
670 | ((>= i limit)) | |
671 | (format out "~:[~;.~]~(~vR~)" | |
672 | sep radix (ldb (byte comp-width i) addr))))))) | |
673 | ||
674 | (export 'reverse-domain) | |
675 | (defgeneric reverse-domain (ipaddr-or-ipn &optional prefix-len) | |
676 | (:documentation "Return a reverse-resolution domain name for IPADDR-OR-IPN. | |
677 | ||
678 | If PREFIX-LEN is nil then it defaults to the length of the network's fixed | |
679 | prefix.") | |
680 | (:method ((ipn ipnet) &optional prefix-len) | |
681 | (let* ((addr (ipnet-net ipn)) | |
682 | (mask (ipnet-mask ipn)) | |
683 | (width (ipaddr-width addr))) | |
684 | (concatenate 'string | |
685 | (reverse-domain-fragment | |
686 | addr | |
687 | (if prefix-len | |
688 | (- width prefix-len) | |
689 | (ipnet-changeable-bits width mask)) | |
690 | width | |
691 | :partialp nil) | |
692 | "." | |
693 | (reverse-domain-suffix addr)))) | |
694 | (:method ((addr ipaddr) &optional prefix-len) | |
695 | (let* ((width (ipaddr-width addr))) | |
696 | (reverse-domain (make-ipnet addr (mask width)) | |
697 | (or prefix-len width))))) | |
9c44003b MW |
698 | |
699 | ;;;-------------------------------------------------------------------------- | |
700 | ;;; Network names and specifiers. | |
701 | ||
e1528fd6 | 702 | (export 'net) |
32ebbe9b MW |
703 | (export 'net-name) |
704 | (export 'net-ipnets) | |
705 | (defclass net () | |
706 | ((name :type string :initarg :name :reader net-name) | |
707 | (ipnets :type list :initarg :ipnets :initform nil :accessor net-ipnets) | |
708 | (next :type unsigned-byte :initform 1 :accessor net-next))) | |
709 | ||
710 | (defmethod print-object ((net net) stream) | |
711 | (print-unreadable-object (net stream :type t) | |
712 | (format stream "~A~@[ = ~{~A~^, ~}~]" | |
713 | (net-name net) | |
714 | (mapcar #'ipnet-string (net-ipnets net))))) | |
9c44003b MW |
715 | |
716 | (defvar *networks* (make-hash-table :test #'equal) | |
717 | "The table of known networks.") | |
718 | ||
e1528fd6 | 719 | (export 'net-find) |
9c44003b MW |
720 | (defun net-find (name) |
721 | "Find a network by NAME." | |
722 | (gethash (string-downcase (stringify name)) *networks*)) | |
9c44003b MW |
723 | (defun (setf net-find) (net name) |
724 | "Make NAME map to NET." | |
725 | (setf (gethash (string-downcase (stringify name)) *networks*) net)) | |
726 | ||
32ebbe9b MW |
727 | (export 'net-must-find) |
728 | (defun net-must-find (name) | |
729 | (or (net-find name) | |
730 | (error "Unknown network ~A." name))) | |
731 | ||
732 | (defun net-ipnet (net family) | |
733 | (find family (net-ipnets net) :key #'ipnet-family)) | |
734 | (defun (setf net-ipnet) (ipnet net family) | |
735 | (assert (eq (ipnet-family ipnet) family)) | |
736 | (let ((ipns (net-ipnets net))) | |
737 | (if (find family ipns :key #'ipnet-family) | |
738 | (nsubstitute ipnet family ipns :key #'ipnet-family) | |
739 | (setf (net-ipnets net) (cons ipnet ipns))))) | |
740 | ||
741 | (defun process-net-form (name addr subnets) | |
f4e0c48f MW |
742 | "Unpack a net-form. |
743 | ||
32ebbe9b MW |
744 | A net-form looks like (NAME ADDR [SUBNET ...]) where: |
745 | ||
746 | * NAME is the name for the network. | |
747 | ||
748 | * ADDR is the subnet address (acceptable to `string-subipnet'); at | |
749 | top-level, this is a plain network address (acceptable to | |
750 | `string-ipnet'). Alternatively (for compatibility) the ADDR for a | |
751 | non-top-level network can be an integer number of addresses to | |
752 | allocate to this subnet; the subnet's base address is implicitly just | |
753 | past the previous subnet's limit address (or, for the first subnet, | |
754 | it's the parent network's base address). This won't work at all well | |
755 | if your subnets have crazy netmasks. | |
756 | ||
757 | * The SUBNETs are further net-forms, of the same form, whose addresses | |
758 | are interpreted relative to the parent network's address. | |
759 | ||
760 | The return value is a list of items of the form (NAME . IPNET)." | |
761 | ||
762 | (labels ((process-subnets (subnets parent) | |
763 | (let ((finger (ipnet-addr parent)) | |
764 | (list nil)) | |
765 | (dolist (subnet subnets list) | |
766 | (destructuring-bind (name addr &rest subs) subnet | |
767 | (let ((net (etypecase addr | |
768 | (integer | |
769 | (when (or (> (count-low-zero-bits addr) | |
770 | (count-low-zero-bits finger)) | |
771 | (not (zerop (logand addr | |
772 | (1- addr))))) | |
773 | (error "Bad subnet size for ~A." name)) | |
774 | (make-ipnet | |
775 | (ipaddr finger (ipnet-net parent)) | |
776 | (ipaddr (- (ash 1 (ipnet-width parent)) | |
777 | addr) | |
778 | (ipnet-net parent)))) | |
779 | ((or string symbol) | |
780 | (string-subipnet parent addr))))) | |
781 | ||
782 | (unless (ipnet-subnetp parent net) | |
783 | (error "Network `~A' (~A) falls outside parent ~A." | |
784 | name (ipnet-string net) (ipnet-string parent))) | |
785 | ||
786 | (dolist (entry list nil) | |
787 | (let ((ipn (cdr entry))) | |
788 | (when (ipnet-overlapp ipn net) | |
789 | (error "Network `~A' (~A) overlaps `~A' (~A)." | |
790 | name (ipnet-string net) | |
791 | (car entry) (ipnet-string ipn))))) | |
792 | ||
793 | (setf finger | |
794 | (1+ (logior | |
795 | (ipnet-addr net) | |
796 | (logxor (ipnet-mask net) | |
797 | (1- (ash 1 (ipnet-width net))))))) | |
798 | ||
799 | (when name | |
800 | (push (cons name net) list)) | |
801 | ||
802 | (when subs | |
803 | (setf list (nconc (process-subnets subs net) | |
804 | list))))))))) | |
805 | ||
806 | (let* ((top (string-ipnet addr)) | |
807 | (list (nreverse (process-subnets subnets top)))) | |
808 | (when name (push (cons name top) list)) | |
809 | list))) | |
9c44003b | 810 | |
e1528fd6 | 811 | (export 'net-create) |
9c44003b | 812 | (defun net-create (name net) |
f4e0c48f MW |
813 | "Construct a new network called NAME and add it to the map. |
814 | ||
32ebbe9b MW |
815 | The NET describes the new network, in a form acceptable to the `ipnet' |
816 | function. A named network may have multiple addresses with different | |
817 | families: each `net-create' call adds a new family, or modifies the net's | |
818 | address in an existing family." | |
819 | (let ((ipn (ipnet net)) | |
820 | (net (net-find name))) | |
821 | (if net | |
822 | (progn (setf (net-ipnet net (ipnet-family ipn)) ipn) net) | |
823 | (setf (net-find name) | |
824 | (make-instance 'net | |
825 | :name (string-downcase (stringify name)) | |
826 | :ipnets (list ipn)))))) | |
9c44003b | 827 | |
e1528fd6 | 828 | (export 'defnet) |
9c44003b | 829 | (defmacro defnet (name net &rest subnets) |
f4e0c48f MW |
830 | "Main network definition macro. |
831 | ||
832 | None of the arguments is evaluated." | |
9c44003b | 833 | `(progn |
32ebbe9b MW |
834 | ,@(mapcar (lambda (item) |
835 | (let ((name (car item)) (ipn (cdr item))) | |
836 | `(net-create ',name ',ipn))) | |
837 | (process-net-form name net subnets)) | |
838 | ',name)) | |
839 | ||
8d531634 MW |
840 | (defun filter-by-family (func form family) |
841 | "Handle a family-switch form. | |
842 | ||
843 | Here, FUNC is a function of two arguments ITEM and FAMILY. FORM is either | |
844 | a list of the form ((FAMILY . ITEM) ...), or an ITEM which is directly | |
845 | acceptable to FUNC. Return a list of the resulting outputs of FUNC." | |
846 | ||
847 | (if (and (listp form) | |
848 | (every (lambda (clause) | |
849 | (and (listp clause) | |
850 | (family-addrclass (car clause)))) | |
851 | form)) | |
852 | (mapcan (lambda (clause) | |
853 | (let ((fam (car clause))) | |
854 | (and (or (eq family t) | |
855 | (eq family fam)) | |
856 | (list (funcall func (cdr clause) fam))))) | |
857 | form) | |
858 | (list (funcall func form family)))) | |
859 | ||
32ebbe9b MW |
860 | (export 'net-parse-to-ipnets) |
861 | (defun net-parse-to-ipnets (form &optional (family t)) | |
6a26c716 MW |
862 | "Parse FORM into a list of ipnet objects. |
863 | ||
864 | The FORM can be any of the following. | |
865 | ||
866 | * NAME -- a named network, established using `net-create' or `defnet' | |
867 | ||
868 | * IPNET -- a network, in a form acceptable to `ipnet' | |
869 | ||
870 | * ((FAMILY . FORM) ...) -- a sequence of networks, filtered by FAMILY" | |
871 | ||
32ebbe9b MW |
872 | (flet ((hack (form family) |
873 | (let* ((form (if (and (consp form) | |
874 | (endp (cdr form))) | |
875 | (car form) | |
876 | form)) | |
877 | (net (net-find form)) | |
878 | (ipns (if net (net-ipnets net) | |
879 | (list (ipnet form))))) | |
880 | (if (eq family t) ipns | |
881 | (remove family ipns | |
882 | :key #'ipnet-family | |
883 | :test-not #'eq))))) | |
8d531634 | 884 | (let* ((ipns (apply #'append (filter-by-family #'hack form family))) |
32ebbe9b MW |
885 | (merged (reduce (lambda (ipns ipn) |
886 | (if (find (ipnet-family ipn) ipns | |
887 | :key #'ipnet-family) | |
888 | ipns | |
889 | (cons ipn ipns))) | |
890 | ipns | |
891 | :initial-value nil))) | |
892 | (or merged (error "No matching addresses."))))) | |
9c44003b | 893 | |
e1528fd6 | 894 | (export 'net-host) |
32ebbe9b MW |
895 | (defun net-host (net-form host &optional (family t)) |
896 | "Return the given HOST on the NET, as an anonymous `host' object. | |
f4e0c48f | 897 | |
88867b1a MW |
898 | HOST may be an index (in range, of course), a suffix (as a symbol or |
899 | string, as for `string-subnet'), or one of the keywords: | |
2f1d381d | 900 | |
32ebbe9b MW |
901 | :next next host, as by net-next-host |
902 | :net network base address | |
903 | :broadcast network broadcast address | |
904 | ||
905 | If FAMILY is not `t', then only return an address with that family; | |
906 | otherwise return all available addresses." | |
907 | (flet ((hosts (ipns host) | |
908 | (mapcar (lambda (ipn) (ipnet-host ipn host)) | |
88867b1a MW |
909 | (if (integerp host) |
910 | (remove host ipns :key #'ipnet-hosts :test #'>=) | |
911 | ipns)))) | |
32ebbe9b MW |
912 | (let* ((net (and (typep net-form '(or string symbol)) |
913 | (net-find net-form))) | |
914 | (ipns (net-parse-to-ipnets net-form family)) | |
915 | (addrs (case host | |
916 | (:next | |
917 | (if net | |
918 | (prog1 (hosts ipns (net-next net)) | |
919 | (incf (net-next net))) | |
920 | (error "Can't use `:next' without a named net."))) | |
921 | (:net (mapcar #'ipnet-net ipns)) | |
922 | (:broadcast (remove nil (mapcar #'ipnet-broadcast ipns))) | |
923 | (t (hosts ipns host))))) | |
924 | (unless addrs | |
925 | (error "No networks have that address.")) | |
926 | (make-instance 'host :addrs addrs)))) | |
927 | ||
928 | ;;;-------------------------------------------------------------------------- | |
929 | ;;; Host names and specifiers. | |
930 | ||
931 | (export 'host) | |
932 | (export 'host-name) | |
933 | (export 'host-addrs) | |
934 | (defclass host () | |
935 | ((name :type (or string null) :initform nil | |
936 | :initarg :name :reader host-name) | |
937 | (addrs :type list :initarg :addrs :initform nil :accessor host-addrs))) | |
938 | ||
939 | (defmethod print-object ((host host) stream) | |
940 | (print-unreadable-object (host stream :type t) | |
941 | (format stream "~:[<anonymous>~;~@*~A~]~@[ = ~{~A~^, ~}~]" | |
942 | (host-name host) | |
943 | (mapcar #'ipaddr-string (host-addrs host))))) | |
944 | ||
945 | (defvar *hosts* (make-hash-table :test #'equal) | |
946 | "The table of known hostnames.") | |
947 | ||
948 | (export 'host-find) | |
949 | (defun host-find (name) | |
950 | "Find a host by NAME." | |
951 | (gethash (string-downcase (stringify name)) *hosts*)) | |
952 | (defun (setf host-find) (addr name) | |
953 | "Make NAME map to ADDR (must be an ipaddr in integer form)." | |
954 | (setf (gethash (string-downcase (stringify name)) *hosts*) addr)) | |
955 | ||
956 | (defun merge-addresses (addrs-a addrs-b) | |
957 | (append (remove-if (lambda (addr) | |
958 | (member (ipaddr-family addr) addrs-b | |
959 | :key #'ipaddr-family)) | |
960 | addrs-a) | |
961 | addrs-b)) | |
962 | ||
963 | (export 'host-parse) | |
964 | (defun host-parse (addr &optional (family t)) | |
965 | "Convert the ADDR into a (possibly anonymous) `host' object. | |
966 | ||
967 | The ADDR can be one of a number of different things. | |
968 | ||
969 | HOST a host name defined using `defhost' | |
970 | ||
971 | (NET INDEX) a particular host in a network | |
972 | ||
973 | IPADDR an address form acceptable to `ipnet' | |
974 | ||
975 | ((FAMILY . ADDR) ...) the above, restricted to a particular address | |
976 | FAMILY (i.e., one of the keywords `:ipv4', | |
977 | etc.)" | |
978 | ||
979 | (labels ((filter-addresses (addrs family) | |
980 | (make-instance 'host | |
981 | :addrs (if (eq family t) addrs | |
982 | (remove family addrs | |
983 | :key #'ipaddr-family | |
984 | :test-not #'eq)))) | |
985 | (host-addresses (host family) | |
986 | (if (eq family t) host | |
987 | (filter-addresses (host-addrs host) family))) | |
988 | (hack (addr family) | |
989 | (let* ((form (listify addr)) | |
990 | (indic (car form)) | |
991 | (host (and (null (cdr form)) | |
992 | (host-find indic)))) | |
993 | (cond (host | |
994 | (host-addresses host family)) | |
995 | ((and (consp (cdr form)) | |
996 | (endp (cddr form))) | |
997 | (net-host (car form) (cadr form) family)) | |
998 | (t | |
999 | (filter-addresses (list (ipaddr indic)) family)))))) | |
8d531634 MW |
1000 | (let* ((list (filter-by-family #'hack addr family)) |
1001 | (host (if (and list (cdr list)) | |
1002 | (make-instance 'host | |
1003 | :addrs (reduce #'merge-addresses | |
1004 | (mapcar #'host-addrs | |
1005 | (reverse list)) | |
1006 | :initial-value nil)) | |
1007 | (car list)))) | |
32ebbe9b MW |
1008 | (unless (host-addrs host) |
1009 | (error "No matching addresses.")) | |
1010 | host))) | |
1011 | ||
1012 | (export 'host-create) | |
1013 | (defun host-create (name addr) | |
1014 | "Make host NAME map to ADDR (anything acceptable to `host-parse')." | |
1015 | (let ((existing (host-find name)) | |
1016 | (new (host-parse addr))) | |
1017 | (if (not existing) | |
1018 | (setf (host-find name) | |
1019 | (make-instance 'host | |
1020 | :name (string-downcase (stringify name)) | |
1021 | :addrs (host-addrs new))) | |
1022 | (progn | |
1023 | (setf (host-addrs existing) | |
1024 | (merge-addresses (host-addrs existing) (host-addrs new))) | |
1025 | existing)))) | |
1026 | ||
1027 | (export 'defhost) | |
1028 | (defmacro defhost (name addr) | |
1029 | "Main host definition macro. Neither NAME nor ADDR is evaluated." | |
1030 | `(progn | |
1031 | (host-create ',name ',addr) | |
1032 | ',name)) | |
9c44003b MW |
1033 | |
1034 | ;;;----- That's all, folks -------------------------------------------------- |