remote: Remove '--system' argument.
[jackhill/guix/guix.git] / gnu / machine / ssh.scm
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1;;; GNU Guix --- Functional package management for GNU
2;;; Copyright © 2019 Jakob L. Kreuze <zerodaysfordays@sdf.lonestar.org>
3;;;
4;;; This file is part of GNU Guix.
5;;;
6;;; GNU Guix is free software; you can redistribute it and/or modify it
7;;; under the terms of the GNU General Public License as published by
8;;; the Free Software Foundation; either version 3 of the License, or (at
9;;; your option) any later version.
10;;;
11;;; GNU Guix is distributed in the hope that it will be useful, but
12;;; WITHOUT ANY WARRANTY; without even the implied warranty of
13;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14;;; GNU General Public License for more details.
15;;;
16;;; You should have received a copy of the GNU General Public License
17;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.
18
19(define-module (gnu machine ssh)
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20 #:use-module (gnu machine)
21 #:autoload (gnu packages gnupg) (guile-gcrypt)
fa9edf09 22 #:use-module (gnu system)
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23 #:use-module (gnu system file-systems)
24 #:use-module (gnu system uuid)
25 #:use-module (guix diagnostics)
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26 #:use-module (guix gexp)
27 #:use-module (guix i18n)
28 #:use-module (guix modules)
29 #:use-module (guix monads)
30 #:use-module (guix records)
31 #:use-module (guix remote)
5c793753 32 #:use-module (guix scripts system reconfigure)
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33 #:use-module (guix ssh)
34 #:use-module (guix store)
fd3119db 35 #:use-module (guix utils)
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36 #:use-module (ice-9 match)
37 #:use-module (srfi srfi-19)
5c793753 38 #:use-module (srfi srfi-26)
2c8e04f1 39 #:use-module (srfi srfi-34)
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40 #:use-module (srfi srfi-35)
41 #:export (managed-host-environment-type
42
43 machine-ssh-configuration
44 machine-ssh-configuration?
45 machine-ssh-configuration
46
47 machine-ssh-configuration-host-name
d84e9b75 48 machine-ssh-configuration-build-locally?
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49 machine-ssh-configuration-port
50 machine-ssh-configuration-user
51 machine-ssh-configuration-session))
52
53;;; Commentary:
54;;;
55;;; This module implements remote evaluation and system deployment for
53f21b3f 56;;; machines that are accessible over SSH and have a known host-name. In the
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57;;; sense of the broader "machine" interface, we describe the environment for
58;;; such machines as 'managed-host.
59;;;
60;;; Code:
61
62\f
63;;;
64;;; Parameters for the SSH client.
65;;;
66
67(define-record-type* <machine-ssh-configuration> machine-ssh-configuration
68 make-machine-ssh-configuration
69 machine-ssh-configuration?
70 this-machine-ssh-configuration
d84e9b75 71 (host-name machine-ssh-configuration-host-name) ; string
2c8e04f1 72 (system machine-ssh-configuration-system) ; string
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73 (build-locally? machine-ssh-configuration-build-locally?
74 (default #t))
75 (port machine-ssh-configuration-port ; integer
76 (default 22))
77 (user machine-ssh-configuration-user ; string
78 (default "root"))
79 (identity machine-ssh-configuration-identity ; path to a private key
80 (default #f))
81 (session machine-ssh-configuration-session ; session
82 (default #f)))
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83
84(define (machine-ssh-session machine)
85 "Return the SSH session that was given in MACHINE's configuration, or create
86one from the configuration's parameters if one was not provided."
87 (maybe-raise-unsupported-configuration-error machine)
88 (let ((config (machine-configuration machine)))
89 (or (machine-ssh-configuration-session config)
90 (let ((host-name (machine-ssh-configuration-host-name config))
91 (user (machine-ssh-configuration-user config))
92 (port (machine-ssh-configuration-port config))
93 (identity (machine-ssh-configuration-identity config)))
94 (open-ssh-session host-name
95 #:user user
96 #:port port
97 #:identity identity)))))
98
99\f
100;;;
101;;; Remote evaluation.
102;;;
103
104(define (managed-host-remote-eval machine exp)
105 "Internal implementation of 'machine-remote-eval' for MACHINE instances with
106an environment type of 'managed-host."
107 (maybe-raise-unsupported-configuration-error machine)
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108 (let ((config (machine-configuration machine)))
109 (remote-eval exp (machine-ssh-session machine)
110 #:build-locally?
111 (machine-ssh-configuration-build-locally? config)
112 #:system
113 (machine-ssh-configuration-system config))))
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114
115\f
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116;;;
117;;; Safety checks.
118;;;
119
120(define (machine-check-file-system-availability machine)
121 "Raise a '&message' error condition if any of the file-systems specified in
122MACHINE's 'system' declaration do not exist on the machine."
123 (define file-systems
124 (filter (lambda (fs)
125 (and (file-system-mount? fs)
126 (not (member (file-system-type fs)
127 %pseudo-file-system-types))
128 (not (memq 'bind-mount (file-system-flags fs)))))
129 (operating-system-file-systems (machine-operating-system machine))))
130
131 (define (check-literal-file-system fs)
132 (define remote-exp
133 #~(catch 'system-error
134 (lambda ()
135 (stat #$(file-system-device fs))
136 #t)
137 (lambda args
138 (system-error-errno args))))
139
140 (mlet %store-monad ((errno (machine-remote-eval machine remote-exp)))
141 (when (number? errno)
142 (raise (condition
143 (&message
144 (message (format #f (G_ "device '~a' not found: ~a")
145 (file-system-device fs)
146 (strerror errno)))))))
147 (return #t)))
148
149 (define (check-labeled-file-system fs)
150 (define remote-exp
151 (with-imported-modules '((gnu build file-systems))
152 #~(begin
153 (use-modules (gnu build file-systems))
154 (find-partition-by-label #$(file-system-label->string
155 (file-system-device fs))))))
156
157 (mlet %store-monad ((result (machine-remote-eval machine remote-exp)))
158 (unless result
159 (raise (condition
160 (&message
161 (message (format #f (G_ "no file system with label '~a'")
162 (file-system-label->string
163 (file-system-device fs))))))))
164 (return #t)))
165
166 (define (check-uuid-file-system fs)
167 (define remote-exp
168 (with-imported-modules (source-module-closure
169 '((gnu build file-systems)
170 (gnu system uuid)))
171 #~(begin
172 (use-modules (gnu build file-systems)
173 (gnu system uuid))
174
175 (define uuid
176 (string->uuid #$(uuid->string (file-system-device fs))))
177
178 (find-partition-by-uuid uuid))))
179
180 (mlet %store-monad ((result (machine-remote-eval machine remote-exp)))
181 (unless result
182 (raise (condition
183 (&message
184 (message (format #f (G_ "no file system with UUID '~a'")
185 (uuid->string (file-system-device fs))))))))
186 (return #t)))
187
188 (mbegin %store-monad
189 (mapm %store-monad check-literal-file-system
190 (filter (lambda (fs)
191 (string? (file-system-device fs)))
192 file-systems))
193 (mapm %store-monad check-labeled-file-system
194 (filter (lambda (fs)
195 (file-system-label? (file-system-device fs)))
196 file-systems))
197 (mapm %store-monad check-uuid-file-system
198 (filter (lambda (fs)
199 (uuid? (file-system-device fs)))
200 file-systems))))
201
202(define (machine-check-initrd-modules machine)
203 "Raise a '&message' error condition if any of the modules needed by
204'needed-for-boot' file systems in MACHINE are not available in the initrd."
205 (define file-systems
206 (filter file-system-needed-for-boot?
207 (operating-system-file-systems (machine-operating-system machine))))
208
209 (define (missing-modules fs)
210 (define remote-exp
211 (let ((device (file-system-device fs)))
212 (with-imported-modules (source-module-closure
213 '((gnu build file-systems)
214 (gnu build linux-modules)
215 (gnu system uuid)))
216 #~(begin
217 (use-modules (gnu build file-systems)
218 (gnu build linux-modules)
219 (gnu system uuid))
220
221 (define dev
222 #$(cond ((string? device) device)
223 ((uuid? device) #~(find-partition-by-uuid
224 (string->uuid
225 #$(uuid->string device))))
226 ((file-system-label? device)
227 #~(find-partition-by-label
228 (file-system-label->string #$device)))))
229
230 (missing-modules dev '#$(operating-system-initrd-modules
231 (machine-operating-system machine)))))))
232 (mlet %store-monad ((missing (machine-remote-eval machine remote-exp)))
233 (return (list fs missing))))
234
235 (mlet %store-monad ((device (mapm %store-monad missing-modules file-systems)))
236 (for-each (match-lambda
237 ((fs missing)
238 (unless (null? missing)
239 (raise (condition
240 (&message
241 (message (format #f (G_ "~a missing modules ~{ ~a~}~%")
242 (file-system-device fs)
243 missing))))))))
244 device)
245 (return #t)))
246
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247(define (machine-check-building-for-appropriate-system machine)
248 "Raise a '&message' error condition if MACHINE is configured to be built
249locally and the 'system' field does not match the '%current-system' reported
250by MACHINE."
251 (let ((config (machine-configuration machine))
252 (system (remote-system (machine-ssh-session machine))))
253 (when (and (machine-ssh-configuration-build-locally? config)
254 (not (string= system (machine-ssh-configuration-system config))))
255 (raise (condition
256 (&message
257 (message (format #f (G_ "incorrect target system \
258('~a' was given, while the system reports that it is '~a')~%")
259 (machine-ssh-configuration-system config)
260 system)))))))
261 (with-monad %store-monad (return #t)))
262
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263(define (check-deployment-sanity machine)
264 "Raise a '&message' error condition if it is clear that deploying MACHINE's
265'system' declaration would fail."
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266 ;; Order is important here -- an incorrect value for 'system' will cause
267 ;; invocations of 'remote-eval' to fail.
fd3119db 268 (mbegin %store-monad
2c8e04f1 269 (machine-check-building-for-appropriate-system machine)
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270 (machine-check-file-system-availability machine)
271 (machine-check-initrd-modules machine)))
272
273\f
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274;;;
275;;; System deployment.
276;;;
277
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278(define (machine-boot-parameters machine)
279 "Monadic procedure returning a list of 'boot-parameters' for the generations
280of MACHINE's system profile, ordered from most recent to oldest."
281 (define bootable-kernel-arguments
282 (@@ (gnu system) bootable-kernel-arguments))
283
284 (define remote-exp
285 (with-extensions (list guile-gcrypt)
286 (with-imported-modules (source-module-closure '((guix config)
287 (guix profiles)))
288 #~(begin
289 (use-modules (guix config)
290 (guix profiles)
291 (ice-9 textual-ports))
292
293 (define %system-profile
294 (string-append %state-directory "/profiles/system"))
295
296 (define (read-file path)
297 (call-with-input-file path
298 (lambda (port)
299 (get-string-all port))))
300
301 (map (lambda (generation)
302 (let* ((system-path (generation-file-name %system-profile
303 generation))
304 (boot-parameters-path (string-append system-path
305 "/parameters"))
306 (time (stat:mtime (lstat system-path))))
307 (list generation
308 system-path
309 time
310 (read-file boot-parameters-path))))
311 (reverse (generation-numbers %system-profile)))))))
312
313 (mlet* %store-monad ((generations (machine-remote-eval machine remote-exp)))
314 (return
315 (map (lambda (generation)
316 (match generation
317 ((generation system-path time serialized-params)
318 (let* ((params (call-with-input-string serialized-params
319 read-boot-parameters))
320 (root (boot-parameters-root-device params))
321 (label (boot-parameters-label params)))
322 (boot-parameters
323 (inherit params)
324 (label
325 (string-append label " (#"
326 (number->string generation) ", "
327 (let ((time (make-time time-utc 0 time)))
328 (date->string (time-utc->date time)
329 "~Y-~m-~d ~H:~M"))
330 ")"))
331 (kernel-arguments
332 (append (bootable-kernel-arguments system-path root)
333 (boot-parameters-kernel-arguments params))))))))
334 generations))))
335
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336(define (deploy-managed-host machine)
337 "Internal implementation of 'deploy-machine' for MACHINE instances with an
338environment type of 'managed-host."
339 (maybe-raise-unsupported-configuration-error machine)
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340 (mlet %store-monad ((_ (check-deployment-sanity machine))
341 (boot-parameters (machine-boot-parameters machine)))
d97ce204 342 (let* ((os (machine-operating-system machine))
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343 (eval (cut machine-remote-eval machine <>))
344 (menu-entries (map boot-parameters->menu-entry boot-parameters))
345 (bootloader-configuration (operating-system-bootloader os))
346 (bootcfg (operating-system-bootcfg os menu-entries)))
347 (mbegin %store-monad
348 (switch-to-system eval os)
349 (upgrade-shepherd-services eval os)
350 (install-bootloader eval bootloader-configuration bootcfg)))))
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351
352\f
353;;;
354;;; Environment type.
355;;;
356
357(define managed-host-environment-type
358 (environment-type
359 (machine-remote-eval managed-host-remote-eval)
360 (deploy-machine deploy-managed-host)
361 (name 'managed-host-environment-type)
53f21b3f 362 (description "Provisioning for machines that are accessible over SSH
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363and have a known host-name. This entails little more than maintaining an SSH
364connection to the host.")))
365
366(define (maybe-raise-unsupported-configuration-error machine)
367 "Raise an error if MACHINE's configuration is not an instance of
368<machine-ssh-configuration>."
369 (let ((config (machine-configuration machine))
370 (environment (environment-type-name (machine-environment machine))))
371 (unless (and config (machine-ssh-configuration? config))
372 (raise (condition
373 (&message
374 (message (format #f (G_ "unsupported machine configuration '~a'
375for environment of type '~a'")
376 config
377 environment))))))))