From 2c8e04f13670c8c7ad8c7195c305960dd1905363 Mon Sep 17 00:00:00 2001 From: "Jakob L. Kreuze" Date: Fri, 9 Aug 2019 14:24:57 -0400 Subject: remote: Build derivations appropriate for the remote's * gnu/machine/ssh.scm (machine-ssh-configuration): Add 'system' field. (managed-host-remote-eval): Pass 'system' field to 'remote-eval'. (machine-check-building-for-appropriate-system): New variable. (check-deployment-sanity): Add call to 'machine-check-building-for-appropriate-system'. * doc/guix.texi (Invoking guix deploy): Describe new 'system' field. * guix/ssh.scm (remote-system): New variable. * guix/remote.scm (remote-eval): Use result of 'remote-system' when lowering the G-Expression. (remote-eval): Add 'system' keyword argument. (trampoline): Return a rather than a . --- doc/guix.texi | 3 +++ 1 file changed, 3 insertions(+) (limited to 'doc') diff --git a/doc/guix.texi b/doc/guix.texi index 734206a4b2..a7facf4701 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -25573,6 +25573,9 @@ with an @code{environment} of @code{managed-host-environment-type}. @table @asis @item @code{host-name} +@item @code{system} +The Nix system type describing the architecture of the machine being deployed +to. This should look something like ``x86_64-linux''. @item @code{port} (default: @code{22}) @item @code{user} (default: @code{"root"}) @item @code{identity} (default: @code{#f}) -- cgit v1.2.3 From 5ea7537b9a650cfa525401c19879080a9cf42e13 Mon Sep 17 00:00:00 2001 From: "Jakob L. Kreuze" Date: Thu, 15 Aug 2019 04:05:04 -0400 Subject: machine: Allow non-root users to deploy. * doc/guix.texi (Invoking guix deploy): Add section describing prerequisites for deploying as a non-root user. * guix/remote.scm (remote-pipe-for-gexp): New optional 'become-command' argument. (%remote-eval): New optional 'become-command' argument. (remote-eval): New 'become-command' keyword argument. * guix/ssh.scm (remote-inferior): New optional 'become-command' argument. (inferior-remote-eval): New optional 'become-command' argument. (remote-authorize-signing-key): New optional 'become-command' argument. * gnu/machine/ssh.scm (machine-become-command): New variable. (managed-host-remote-eval): Invoke 'remote-eval' with the '#:become-command' keyword. (deploy-managed-host): Invoke 'remote-authorize-signing-key' with the '#:become-command' keyword. --- doc/guix.texi | 10 ++++++++++ gnu/machine/ssh.scm | 8 ++++++++ guix/remote.scm | 57 +++++++++++++++++++++++++++++++++-------------------- guix/ssh.scm | 25 ++++++++++++++++------- 4 files changed, 72 insertions(+), 28 deletions(-) (limited to 'doc') diff --git a/doc/guix.texi b/doc/guix.texi index a7facf4701..e5cec7ad25 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -25514,6 +25514,7 @@ evaluates to. As an example, @var{file} might contain a definition like this: (environment managed-host-environment-type) (configuration (machine-ssh-configuration (host-name "localhost") + (user "alice") (identity "./id_rsa") (port 2222))))) @end example @@ -25546,6 +25547,15 @@ accepts store items it receives from the coordinator: # guix archive --authorize < coordinator-public-key.txt @end example +@code{user}, in this example, specifies the name of the user account to log in +as to perform the deployment. Its default value is @code{root}, but root +login over SSH may be forbidden in some cases. To work around this, +@command{guix deploy} can log in as an unprivileged user and employ +@code{sudo} to escalate privileges. This will only work if @code{sudo} is +currently installed on the remote and can be invoked non-interactively as +@code{user}. That is: the line in @code{sudoers} granting @code{user} the +ability to use @code{sudo} must contain the @code{NOPASSWD} tag. + @deftp {Data Type} machine This is the data type representing a single machine in a heterogeneous Guix deployment. diff --git a/gnu/machine/ssh.scm b/gnu/machine/ssh.scm index 670990a633..fb15d39e61 100644 --- a/gnu/machine/ssh.scm +++ b/gnu/machine/ssh.scm @@ -101,6 +101,14 @@ one from the configuration's parameters if one was not provided." ;;; Remote evaluation. ;;; +(define (machine-become-command machine) + "Return as a list of strings the program and arguments necessary to run a +shell command with escalated privileges for MACHINE's configuration." + (if (string= "root" (machine-ssh-configuration-user + (machine-configuration machine))) + '() + '("/run/setuid-programs/sudo" "-n" "--"))) + (define (managed-host-remote-eval machine exp) "Internal implementation of 'machine-remote-eval' for MACHINE instances with an environment type of 'managed-host." diff --git a/guix/remote.scm b/guix/remote.scm index bcac64ea7a..d8124e41ab 100644 --- a/guix/remote.scm +++ b/guix/remote.scm @@ -27,6 +27,8 @@ #:use-module (guix utils) #:use-module (ssh popen) #:use-module (srfi srfi-1) + #:use-module (srfi srfi-34) + #:use-module (srfi srfi-35) #:use-module (ice-9 match) #:export (remote-eval)) @@ -41,29 +43,41 @@ ;;; ;;; Code: -(define (remote-pipe-for-gexp lowered session) - "Return a remote pipe for the given SESSION to evaluate LOWERED." +(define* (remote-pipe-for-gexp lowered session #:optional become-command) + "Return a remote pipe for the given SESSION to evaluate LOWERED. If +BECOME-COMMAND is given, use that to invoke the remote Guile REPL." (define shell-quote (compose object->string object->string)) - (apply open-remote-pipe* session OPEN_READ - (string-append (derivation-input-output-path - (lowered-gexp-guile lowered)) - "/bin/guile") - "--no-auto-compile" - (append (append-map (lambda (directory) - `("-L" ,directory)) - (lowered-gexp-load-path lowered)) - (append-map (lambda (directory) - `("-C" ,directory)) - (lowered-gexp-load-path lowered)) - `("-c" - ,(shell-quote (lowered-gexp-sexp lowered)))))) + (define repl-command + (append (or become-command '()) + (list + (string-append (derivation-input-output-path + (lowered-gexp-guile lowered)) + "/bin/guile") + "--no-auto-compile") + (append-map (lambda (directory) + `("-L" ,directory)) + (lowered-gexp-load-path lowered)) + (append-map (lambda (directory) + `("-C" ,directory)) + (lowered-gexp-load-path lowered)) + `("-c" + ,(shell-quote (lowered-gexp-sexp lowered))))) -(define (%remote-eval lowered session) + (let ((pipe (apply open-remote-pipe* session OPEN_READ repl-command))) + (when (eof-object? (peek-char pipe)) + (raise (condition + (&message + (message (format #f (G_ "failed to run '~{~a~^ ~}'") + repl-command)))))) + pipe)) + +(define* (%remote-eval lowered session #:optional become-command) "Evaluate LOWERED, a lowered gexp, in SESSION. This assumes that all the -prerequisites of EXP are already available on the host at SESSION." - (let* ((pipe (remote-pipe-for-gexp lowered session)) +prerequisites of EXP are already available on the host at SESSION. If +BECOME-COMMAND is given, use that to invoke the remote Guile REPL." + (let* ((pipe (remote-pipe-for-gexp lowered session become-command)) (result (read-repl-response pipe))) (close-port pipe) result)) @@ -92,7 +106,8 @@ result to the current output port using the (guix repl) protocol." (build-locally? #t) (system (%current-system)) (module-path %load-path) - (socket-name "/var/guix/daemon-socket/socket")) + (socket-name "/var/guix/daemon-socket/socket") + (become-command #f)) "Evaluate EXP, a gexp, on the host at SESSION, an SSH session. Ensure that all the elements EXP refers to are built and deployed to SESSION beforehand. When BUILD-LOCALLY? is true, said dependencies are built locally and sent to @@ -119,7 +134,7 @@ remote store." (built-derivations inputs) ((store-lift send-files) to-send remote #:recursive? #t) (return (close-connection remote)) - (return (%remote-eval lowered session)))) + (return (%remote-eval lowered session become-command)))) (let ((to-send (append (map (compose derivation-file-name derivation-input-derivation) inputs) @@ -128,4 +143,4 @@ remote store." ((store-lift send-files) to-send remote #:recursive? #t) (return (build-derivations remote inputs)) (return (close-connection remote)) - (return (%remote-eval lowered session))))))) + (return (%remote-eval lowered session become-command))))))) diff --git a/guix/ssh.scm b/guix/ssh.scm index 9b5ca68894..90311127a1 100644 --- a/guix/ssh.scm +++ b/guix/ssh.scm @@ -98,16 +98,27 @@ specifies; otherwise use them. Throw an error on failure." (message (format #f (G_ "SSH connection to '~a' failed: ~a~%") host (get-error session)))))))))) -(define (remote-inferior session) - "Return a remote inferior for the given SESSION." - (let ((pipe (open-remote-pipe* session OPEN_BOTH - "guix" "repl" "-t" "machine"))) +(define* (remote-inferior session #:optional become-command) + "Return a remote inferior for the given SESSION. If BECOME-COMMAND is +given, use that to invoke the remote Guile REPL." + (let* ((repl-command (append (or become-command '()) + '("guix" "repl" "-t" "machine"))) + (pipe (apply open-remote-pipe* session OPEN_BOTH repl-command))) + ;; XXX: 'channel-get-exit-status' would be better here, but hangs if the + ;; process does succeed. This doesn't reflect the documentation, so it's + ;; possible that it's a bug in guile-ssh. + (when (eof-object? (peek-char pipe)) + (raise (condition + (&message + (message (format #f (G_ "failed to run '~{~a~^ ~}'") + repl-command)))))) (port->inferior pipe))) -(define (inferior-remote-eval exp session) +(define* (inferior-remote-eval exp session #:optional become-command) "Evaluate EXP in a new inferior running in SESSION, and close the inferior -right away." - (let ((inferior (remote-inferior session))) +right away. If BECOME-COMMAND is given, use that to invoke the remote Guile +REPL." + (let ((inferior (remote-inferior session become-command))) (dynamic-wind (const #t) (lambda () -- cgit v1.2.3 From 3033d59ac9a747b42a1fa6ca6664d4fbc62ca117 Mon Sep 17 00:00:00 2001 From: "Jakob L. Kreuze" Date: Thu, 15 Aug 2019 04:06:41 -0400 Subject: machine: Automatically authorize the coordinator's signing key. * guix/ssh.scm (remote-authorize-signing-key): New variable. * gnu/machine/ssh.scm (deploy-managed-host): Authorize coordinator's signing key before any invocations of 'remote-eval'. (deploy-managed-host): Display an error if a signing key does not exist. * doc/guix.texi (Invoking guix deploy): Remove section describing manual signing key authorization. (Invoking guix deploy): Add section describing the 'authorize?' field. --- doc/guix.texi | 3 +++ gnu/machine/ssh.scm | 33 ++++++++++++++++++++++++++------- guix/ssh.scm | 23 +++++++++++++++++++++++ 3 files changed, 52 insertions(+), 7 deletions(-) (limited to 'doc') diff --git a/doc/guix.texi b/doc/guix.texi index e5cec7ad25..d80f62970d 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -25586,6 +25586,9 @@ with an @code{environment} of @code{managed-host-environment-type}. @item @code{system} The Nix system type describing the architecture of the machine being deployed to. This should look something like ``x86_64-linux''. +@item @code{authorize?} (default: @code{#t}) +If true, the coordinator's signing key will be added to the remote's ACL +keyring. @item @code{port} (default: @code{22}) @item @code{user} (default: @code{"root"}) @item @code{identity} (default: @code{#f}) diff --git a/gnu/machine/ssh.scm b/gnu/machine/ssh.scm index 4b5d5fe3a2..ac3aa3e370 100644 --- a/gnu/machine/ssh.scm +++ b/gnu/machine/ssh.scm @@ -28,13 +28,16 @@ #:use-module (guix i18n) #:use-module (guix modules) #:use-module (guix monads) + #:use-module (guix pki) #:use-module (guix records) #:use-module (guix remote) #:use-module (guix scripts system reconfigure) #:use-module (guix ssh) #:use-module (guix store) #:use-module (guix utils) + #:use-module (gcrypt pk-crypto) #:use-module (ice-9 match) + #:use-module (ice-9 textual-ports) #:use-module (srfi srfi-1) #:use-module (srfi srfi-19) #:use-module (srfi srfi-26) @@ -48,6 +51,7 @@ machine-ssh-configuration-host-name machine-ssh-configuration-build-locally? + machine-ssh-configuration-authorize? machine-ssh-configuration-port machine-ssh-configuration-user machine-ssh-configuration-session)) @@ -70,17 +74,19 @@ make-machine-ssh-configuration machine-ssh-configuration? this-machine-ssh-configuration - (host-name machine-ssh-configuration-host-name) ; string - (system machine-ssh-configuration-system) ; string - (build-locally? machine-ssh-configuration-build-locally? + (host-name machine-ssh-configuration-host-name) ; string + (system machine-ssh-configuration-system) ; string + (build-locally? machine-ssh-configuration-build-locally? ; boolean (default #t)) - (port machine-ssh-configuration-port ; integer + (authorize? machine-ssh-configuration-authorize? ; boolean + (default #t)) + (port machine-ssh-configuration-port ; integer (default 22)) - (user machine-ssh-configuration-user ; string + (user machine-ssh-configuration-user ; string (default "root")) - (identity machine-ssh-configuration-identity ; path to a private key + (identity machine-ssh-configuration-identity ; path to a private key (default #f)) - (session machine-ssh-configuration-session ; session + (session machine-ssh-configuration-session ; session (default #f))) (define (machine-ssh-session machine) @@ -359,6 +365,19 @@ the 'should-roll-back' field set to SHOULD-ROLL-BACK?" "Internal implementation of 'deploy-machine' for MACHINE instances with an environment type of 'managed-host." (maybe-raise-unsupported-configuration-error machine) + (when (machine-ssh-configuration-authorize? + (machine-configuration machine)) + (unless (file-exists? %public-key-file) + (raise (condition + (&message + (message (format #f (G_ "no signing key '~a'. \ +have you run 'guix archive --generate-key?'") + %public-key-file)))))) + (remote-authorize-signing-key (call-with-input-file %public-key-file + (lambda (port) + (string->canonical-sexp + (get-string-all port)))) + (machine-ssh-session machine))) (mlet %store-monad ((_ (check-deployment-sanity machine)) (boot-parameters (machine-boot-parameters machine))) (let* ((os (machine-operating-system machine)) diff --git a/guix/ssh.scm b/guix/ssh.scm index 90311127a1..24834c6f68 100644 --- a/guix/ssh.scm +++ b/guix/ssh.scm @@ -21,6 +21,7 @@ #:use-module (guix inferior) #:use-module (guix i18n) #:use-module ((guix utils) #:select (&fix-hint)) + #:use-module (gcrypt pk-crypto) #:use-module (ssh session) #:use-module (ssh auth) #:use-module (ssh key) @@ -40,6 +41,7 @@ remote-daemon-channel connect-to-remote-daemon remote-system + remote-authorize-signing-key send-files retrieve-files retrieve-files* @@ -300,6 +302,27 @@ the machine on the other end of SESSION." (inferior-remote-eval '(begin (use-modules (guix utils)) (%current-system)) session)) +(define (remote-authorize-signing-key key session) + "Send KEY, a canonical sexp containing a public key, over SESSION and add it +to the system ACL file if it has not yet been authorized." + (inferior-remote-eval + `(begin + (use-modules (guix build utils) + (guix pki) + (guix utils) + (gcrypt pk-crypto) + (srfi srfi-26)) + + (define acl (current-acl)) + (define key (string->canonical-sexp ,(canonical-sexp->string key))) + + (unless (authorized-key? key) + (let ((acl (public-keys->acl (cons key (acl->public-keys acl))))) + (mkdir-p (dirname %acl-file)) + (with-atomic-file-output %acl-file + (cut write-acl acl <>))))) + session)) + (define* (send-files local files remote #:key recursive? -- cgit v1.2.3 From 3967a946c6b36bdd51bd0f11b75ad1f7ef3d4674 Mon Sep 17 00:00:00 2001 From: "Jakob L. Kreuze" Date: Thu, 15 Aug 2019 04:07:19 -0400 Subject: doc: Add description of 'build-locally?'. * doc/guix.texi (Invoking guix deploy): Add section describing the 'build-locally?' field of 'managed-host-environment-type'. --- doc/guix.texi | 2 ++ 1 file changed, 2 insertions(+) (limited to 'doc') diff --git a/doc/guix.texi b/doc/guix.texi index d80f62970d..043851e418 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -25583,6 +25583,8 @@ with an @code{environment} of @code{managed-host-environment-type}. @table @asis @item @code{host-name} +@item @code{build-locally?} (default: @code{#t}) +If false, system derivations will be built on the machine being deployed to. @item @code{system} The Nix system type describing the architecture of the machine being deployed to. This should look something like ``x86_64-linux''. -- cgit v1.2.3