summaryrefslogtreecommitdiff
path: root/guix/scripts/challenge.scm
blob: 65e2427033b9267e4458bcd1dafd002150d7ad08 (about) (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2015, 2016, 2017, 2019, 2020 Ludovic Courtès <ludo@gnu.org>
;;;
;;; This file is part of GNU Guix.
;;;
;;; GNU Guix is free software; you can redistribute it and/or modify it
;;; under the terms of the GNU General Public License as published by
;;; the Free Software Foundation; either version 3 of the License, or (at
;;; your option) any later version.
;;;
;;; GNU Guix 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 GNU Guix.  If not, see <http://www.gnu.org/licenses/>.

(define-module (guix scripts challenge)
  #:use-module (guix ui)
  #:use-module (guix scripts)
  #:use-module (guix store)
  #:use-module (guix utils)
  #:use-module (guix grafts)
  #:use-module (guix monads)
  #:use-module (guix base32)
  #:use-module (guix packages)
  #:use-module ((guix progress) #:hide (dump-port*))
  #:use-module (guix serialization)
  #:use-module (guix scripts substitute)
  #:use-module (rnrs bytevectors)
  #:autoload   (guix http-client) (http-fetch)
  #:use-module ((guix build syscalls) #:select (terminal-columns))
  #:use-module (gcrypt hash)
  #:use-module (srfi srfi-1)
  #:use-module (srfi srfi-9)
  #:use-module (srfi srfi-11)
  #:use-module (srfi srfi-26)
  #:use-module (srfi srfi-34)
  #:use-module (srfi srfi-37)
  #:use-module (ice-9 match)
  #:use-module (ice-9 vlist)
  #:use-module (ice-9 format)
  #:use-module (ice-9 ftw)
  #:use-module (web uri)
  #:export (compare-contents

            comparison-report?
            comparison-report-item
            comparison-report-result
            comparison-report-local-sha256
            comparison-report-narinfos

            comparison-report-match?
            comparison-report-mismatch?
            comparison-report-inconclusive?

            differing-files
            call-with-mismatches

            guix-challenge))

;;; Commentary:
;;;
;;; Challenge substitute servers, checking whether they provide the same
;;; binaries as those built locally.
;;;
;;; Here we completely bypass the daemon to access substitutes.  This is
;;; because we want to be able to report fine-grain information about
;;; discrepancies: We need to show the URL of the offending nar, its hash, and
;;; so on.
;;;
;;; Code:

(define ensure-store-item                         ;XXX: move to (guix ui)?
  (@@ (guix scripts size) ensure-store-item))

;; Representation of a comparison report for ITEM.
(define-record-type <comparison-report>
  (%comparison-report item result local-sha256 narinfos)
  comparison-report?
  (item         comparison-report-item)    ;string, /gnu/store/… item
  (result       comparison-report-result)  ;'match | 'mismatch | 'inconclusive
  (local-sha256 comparison-report-local-sha256)   ;bytevector | #f
  (narinfos     comparison-report-narinfos))      ;list of <narinfo>

(define-syntax comparison-report
  ;; Some sort of a an enum to make sure 'result' is correct.
  (syntax-rules (match mismatch inconclusive)
    ((_ item 'match rest ...)
     (%comparison-report item 'match rest ...))
    ((_ item 'mismatch rest ...)
     (%comparison-report item 'mismatch rest ...))
    ((_ item 'inconclusive rest ...)
     (%comparison-report item 'inconclusive rest ...))))

(define (comparison-report-predicate result)
  "Return a predicate that returns true when pass a REPORT that has RESULT."
  (lambda (report)
    (eq? (comparison-report-result report) result)))

(define comparison-report-mismatch?
  (comparison-report-predicate 'mismatch))

(define comparison-report-match?
  (comparison-report-predicate 'match))

(define comparison-report-inconclusive?
  (comparison-report-predicate 'inconclusive))

(define (locally-built? store item)
  "Return true if ITEM was built locally."
  ;; XXX: For now approximate it by checking whether there's a build log for
  ;; ITEM.  There could be false negatives, if logs have been removed.
  (->bool (log-file store item)))

(define (query-locally-built-hash item)
  "Return the hash of ITEM, a store item, if ITEM was built locally.
Otherwise return #f."
  (lambda (store)
    (guard (c ((store-protocol-error? c)
               (values #f store)))
      (if (locally-built? store item)
          (values (query-path-hash store item) store)
          (values #f store)))))

(define-syntax-rule (report args ...)
  (format (current-error-port) args ...))

(define (compare-contents items servers)
  "Challenge the substitute servers whose URLs are listed in SERVERS by
comparing the hash of the substitutes of ITEMS that they serve.  Return the
list of <comparison-report> objects.

This procedure does not authenticate narinfos from SERVERS, nor does it verify
that they are signed by an authorized public keys.  The reason is that, by
definition, we may want to target unknown servers.  Furthermore, no risk is
taken since we do not import the archives."
  (define (compare item reference)
    ;; Return a procedure to compare the hash of ITEM with REFERENCE.
    (lambda (narinfo url)
      (or (not narinfo)
          (let ((value (narinfo-hash->sha256 (narinfo-hash narinfo))))
            (bytevector=? reference value)))))

  (define (select-reference item narinfos urls)
    ;; Return a "reference" narinfo among NARINFOS.
    (match narinfos
      ((first narinfos ...)
       (match servers
         ((url urls ...)
          (if (not first)
              (select-reference item narinfos urls)
              (narinfo-hash->sha256 (narinfo-hash first))))))))

  (mlet* %store-monad ((local     (mapm %store-monad
                                        query-locally-built-hash items))
                       (remote -> (append-map (cut lookup-narinfos <> items)
                                              servers))
                       ;; No 'assert-valid-narinfo' on purpose.
                       (narinfos -> (fold (lambda (narinfo vhash)
                                            (vhash-cons (narinfo-path narinfo) narinfo
                                                        vhash))
                                          vlist-null
                                          remote)))
    (return (map (lambda (item local)
                   (match (vhash-fold* cons '() item narinfos)
                     (()                          ;no substitutes
                      (comparison-report item 'inconclusive local '()))
                     ((narinfo)
                      (if local
                          (if ((compare item local) narinfo (first servers))
                              (comparison-report item 'match
                                                 local (list narinfo))
                              (comparison-report item 'mismatch
                                                 local (list narinfo)))
                          (comparison-report item 'inconclusive
                                             local (list narinfo))))
                     ((narinfos ...)
                      (let ((reference
                             (or local (select-reference item narinfos
                                                         servers))))
                        (if (every (compare item reference) narinfos servers)
                            (comparison-report item 'match
                                               local narinfos)
                            (comparison-report item 'mismatch
                                               local narinfos))))))
                 items
                 local))))


;;;
;;; Reporting.
;;;

(define (port-sha256* port size)
  ;; Like 'port-sha256', but limited to SIZE bytes.
  (let-values (((out get) (open-sha256-port)))
    (dump-port* port out size)
    (close-port out)
    (get)))

(define (archive-contents port)
  "Return a list representing the files contained in the nar read from PORT."
  (fold-archive (lambda (file type contents result)
                  (match type
                    ((or 'regular 'executable)
                     (match contents
                       ((port . size)
                        (cons `(,file ,type ,(port-sha256* port size))
                              result))))
                    ('directory result)
                    ('symlink
                     (cons `(,file ,type ,contents) result))))
                '()
                port
                ""))

(define (store-item-contents item)
  "Return a list of files and contents for ITEM in the same format as
'archive-contents'."
  (file-system-fold (const #t)                    ;enter?
                    (lambda (file stat result)    ;leaf
                      (define short
                        (string-drop file (string-length item)))

                      (match (stat:type stat)
                        ('regular
                         (let ((size (stat:size stat))
                               (type (if (zero? (logand (stat:mode stat)
                                                        #o100))
                                         'regular
                                         'executable)))
                           (cons `(,short ,type
                                          ,(call-with-input-file file
                                             (cut port-sha256* <> size)))
                                 result)))
                        ('symlink
                         (cons `(,short symlink ,(readlink file))
                               result))))
                    (lambda (directory stat result) result)  ;down
                    (lambda (directory stat result) result)  ;up
                    (lambda (file stat result) result)       ;skip
                    (lambda (file stat errno result) result) ;error
                    '()
                    item
                    lstat))

(define (call-with-nar narinfo proc)
  "Call PROC with an input port from which it can read the nar pointed to by
NARINFO."
  (let*-values (((uri compression size)
                 (narinfo-best-uri narinfo))
                ((port response)
                 (http-fetch uri)))
    (define reporter
      (progress-reporter/file (narinfo-path narinfo) size
                              #:abbreviation (const (uri-host uri))))

    (define result
      (call-with-decompressed-port (string->symbol compression)
          (progress-report-port reporter port)
        proc))

    (close-port port)
    (erase-current-line (current-output-port))
    result))

(define (narinfo-contents narinfo)
  "Fetch the nar described by NARINFO and return a list representing the file
it contains."
  (call-with-nar narinfo archive-contents))

(define (differing-files comparison-report)
  "Return a list of files that differ among the nars and possibly the local
store item specified in COMPARISON-REPORT."
  (define contents
    (map narinfo-contents
         (comparison-report-narinfos comparison-report)))

  (define local-contents
    (and (comparison-report-local-sha256 comparison-report)
         (store-item-contents (comparison-report-item comparison-report))))

  (match (apply lset-difference equal?
                (take (delete-duplicates
                       (if local-contents
                           (cons local-contents contents)
                           contents))
                      2))
    (((files _ ...) ...)
     files)))

(define (report-differing-files comparison-report)
  "Report differences among the nars and possibly the local store item
specified in COMPARISON-REPORT."
  (match (differing-files comparison-report)
    (()
     #t)
    ((files ...)
     (format #t (N_ "  differing file:~%"
                    "  differing files:~%"
                    (length files)))
     (format #t     "~{    ~a~%~}" files))))

(define (call-with-mismatches comparison-report proc)
  "Call PROC with two directories containing the mismatching store items."
  (define local-hash
    (comparison-report-local-sha256 comparison-report))

  (define narinfos
    (comparison-report-narinfos comparison-report))

  (call-with-temporary-directory
   (lambda (directory1)
     (call-with-temporary-directory
      (lambda (directory2)
        (define narinfo1
          (if local-hash
              (find (lambda (narinfo)
                      (not (bytevector=? (narinfo-hash->sha256
                                          (narinfo-hash narinfo))
                                         local-hash)))
                    narinfos)
              (first (comparison-report-narinfos comparison-report))))

        (define narinfo2
          (and (not local-hash)
               (find (lambda (narinfo)
                       (not (eq? narinfo narinfo1)))
                     narinfos)))

        (rmdir directory1)
        (call-with-nar narinfo1 (cut restore-file <> directory1))
        (when narinfo2
          (rmdir directory2)
          (call-with-nar narinfo2 (cut restore-file <> directory2)))
        (proc directory1
              (if local-hash
                  (comparison-report-item comparison-report)
                  directory2)))))))

(define %diffoscope-command
  ;; Default external diff command.  Pass "--exclude-directory-metadata" so
  ;; that the mtime/ctime differences are ignored.
  '("diffoscope" "--exclude-directory-metadata=yes"))

(define* (report-differing-files/external comparison-report
                                          #:optional
                                          (command %diffoscope-command))
  "Run COMMAND to show the file-level differences for the mismatches in
COMPARISON-REPORT."
  (call-with-mismatches comparison-report
                        (lambda (directory1 directory2)
                          (apply system*
                                 (append command
                                         (list directory1 directory2))))))

(define* (summarize-report comparison-report
                           #:key
                           (report-differences (const #f))
                           (hash->string bytevector->nix-base32-string)
                           verbose?)
  "Write to the current error port a summary of COMPARISON-REPORT, a
<comparison-report> object.  When VERBOSE?, display matches in addition to
mismatches and inconclusive reports.  Upon mismatch, call REPORT-DIFFERENCES
with COMPARISON-REPORT."
  (define (report-hashes item local narinfos)
    (if local
        (report (G_ "  local hash: ~a~%") (hash->string local))
        (report (G_ "  no local build for '~a'~%") item))
    (for-each (lambda (narinfo)
                (report (G_ "  ~50a: ~a~%")
                        (uri->string (narinfo-best-uri narinfo))
                        (hash->string
                         (narinfo-hash->sha256 (narinfo-hash narinfo)))))
              narinfos))

  (match comparison-report
    (($ <comparison-report> item 'mismatch local (narinfos ...))
     (report (G_ "~a contents differ:~%") item)
     (report-hashes item local narinfos)
     (report-differences comparison-report))
    (($ <comparison-report> item 'inconclusive #f narinfos)
     (warning (G_ "could not challenge '~a': no local build~%") item))
    (($ <comparison-report> item 'inconclusive locals ())
     (warning (G_ "could not challenge '~a': no substitutes~%") item))
    (($ <comparison-report> item 'match local (narinfos ...))
     (when verbose?
       (report (G_ "~a contents match:~%") item)
       (report-hashes item local narinfos)))))

(define (summarize-report-list reports)
  "Display the overall summary of REPORTS."
  (let ((total         (length reports))
        (inconclusive  (count comparison-report-inconclusive? reports))
        (matches       (count comparison-report-match? reports))
        (discrepancies (count comparison-report-mismatch? reports)))
    (report (G_ "~h store items were analyzed:~%") total)
    (report (G_ "  - ~h (~,1f%) were identical~%")
            matches (* 100. (/ matches total)))
    (report (G_ "  - ~h (~,1f%) differed~%")
            discrepancies (* 100. (/ discrepancies total)))
    (report (G_ "  - ~h (~,1f%) were inconclusive~%")
            inconclusive (* 100. (/ inconclusive total)))))


;;;
;;; Command-line options.
;;;

(define (show-help)
  (display (G_ "Usage: guix challenge [PACKAGE...]
Challenge the substitutes for PACKAGE... provided by one or more servers.\n"))
  (display (G_ "
      --substitute-urls=URLS
                         compare build results with those at URLS"))
  (display (G_ "
      -v, --verbose      show details about successful comparisons"))
  (display (G_ "
          --diff=MODE    show differences according to MODE"))
  (newline)
  (display (G_ "
  -h, --help             display this help and exit"))
  (display (G_ "
  -V, --version          display version information and exit"))
  (newline)
  (show-bug-report-information))

(define %options
  (list  (option '(#\h "help") #f #f
                 (lambda args
                   (show-help)
                   (exit 0)))
         (option '(#\V "version") #f #f
                 (lambda args
                   (show-version-and-exit "guix challenge")))

         (option '("diff") #t #f
                 (lambda (opt name arg result . rest)
                   (define mode
                     (match arg
                       ("none" (const #t))
                       ("simple" report-differing-files)
                       ("diffoscope" report-differing-files/external)
                       ((and (? (cut string-prefix? "/" <>)) command)
                        (cute report-differing-files/external <>
                              (string-tokenize command)))
                       (_ (leave (G_ "~a: unknown diff mode~%") arg))))

                   (apply values
                          (alist-cons 'difference-report mode result)
                          rest)))

         (option '("substitute-urls") #t #f
                 (lambda (opt name arg result . rest)
                   (apply values
                          (alist-cons 'substitute-urls
                                      (string-tokenize arg)
                                      (alist-delete 'substitute-urls result))
                          rest)))
         (option '("verbose" #\v) #f #f
                 (lambda (opt name arg result . rest)
                   (apply values
                          (alist-cons 'verbose? #t result)
                          rest)))))

(define %default-options
  `((system . ,(%current-system))
    (substitute-urls . ,%default-substitute-urls)
    (difference-report . ,report-differing-files)))


;;;
;;; Entry point.
;;;

(define (guix-challenge . args)
  (with-error-handling
    (let* ((opts     (parse-command-line args %options (list %default-options)
                                         #:build-options? #f))
           (files    (filter-map (match-lambda
                                   (('argument . file) file)
                                   (_ #f))
                                 opts))
           (system   (assoc-ref opts 'system))
           (urls     (assoc-ref opts 'substitute-urls))
           (diff     (assoc-ref opts 'difference-report))
           (verbose? (assoc-ref opts 'verbose?)))
      (leave-on-EPIPE
       (with-store store
         ;; Disable grafts since substitute servers normally provide only
         ;; ungrafted stuff.
         (parameterize ((%graft? #f)
                        (current-terminal-columns (terminal-columns)))
           (let ((files (match files
                          (()
                           (filter (cut locally-built? store <>)
                                   (live-paths store)))
                          (x
                           files))))
             (set-build-options store
                                #:use-substitutes? #f)

             (run-with-store store
               (mlet* %store-monad ((items   (mapm %store-monad
                                                   ensure-store-item files))
                                    (reports (compare-contents items urls)))
                 (for-each (cut summarize-report <> #:verbose? verbose?
                                #:report-differences diff)
                           reports)
                 (report "\n")
                 (summarize-report-list reports)

                 (exit (cond ((any comparison-report-mismatch? reports) 2)
                             ((every comparison-report-match? reports) 0)
                             (else 1))))
               #:system system))))))))

;;; challenge.scm ends here