;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2016, 2017, 2018, 2019 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2016, 2017, 2018, 2019, 2020 Ludovic Courtès <ludo@gnu.org>
;;;
;;; This file is part of GNU Guix.
;;;
#:use-module (guix store)
#:use-module (guix inferior)
#:use-module (guix i18n)
- #:use-module ((guix utils) #:select (&fix-hint))
+ #:use-module ((guix diagnostics)
+ #:select (info &fix-hint formatted-message))
+ #:use-module ((guix progress)
+ #:select (progress-bar
+ erase-current-line current-terminal-columns))
#:use-module (gcrypt pk-crypto)
#:use-module (ssh session)
#:use-module (ssh auth)
#:use-module (ice-9 match)
#:use-module (ice-9 format)
#:use-module (ice-9 binary-ports)
+ #:use-module (ice-9 vlist)
#:export (open-ssh-session
+ authenticate-server*
+
remote-inferior
remote-daemon-channel
connect-to-remote-daemon
retrieve-files*
remote-store-host
- report-guile-error
- report-module-error))
+ report-guile-error))
;;; Commentary:
;;;
(define %compression
"zlib@openssh.com,zlib")
+(define (host-key->type+key host-key)
+ "Destructure HOST-KEY, an OpenSSH host key string, and return two values:
+its key type as a symbol, and the actual base64-encoded string."
+ (define (type->symbol type)
+ (and (string-prefix? "ssh-" type)
+ (string->symbol (string-drop type 4))))
+
+ (match (string-tokenize host-key)
+ ((type key x)
+ (values (type->symbol type) key))
+ ((type key)
+ (values (type->symbol type) key))))
+
+(define (authenticate-server* session key)
+ "Make sure the server for SESSION has the given KEY, where KEY is a string
+such as \"ssh-ed25519 AAAAC3Nz… root@example.org\". Raise an exception if the
+actual key does not match."
+ (let-values (((server) (get-server-public-key session))
+ ((type key) (host-key->type+key key)))
+ (unless (and (or (not (get-key-type server))
+ (eq? (get-key-type server) type))
+ (string=? (public-key->string server) key))
+ ;; Key mismatch: something's wrong. XXX: It could be that the server
+ ;; provided its Ed25519 key when we where expecting its RSA key. XXX:
+ ;; Guile-SSH 0.10.1 doesn't know about ed25519 keys and 'get-key-type'
+ ;; returns #f in that case.
+ (raise (formatted-message (G_ "server at '~a' returned host key \
+'~a' of type '~a' instead of '~a' of type '~a'~%")
+ (session-get session 'host)
+ (public-key->string server)
+ (get-key-type server)
+ key type)))))
+
(define* (open-ssh-session host #:key user port identity
- (compression %compression))
+ host-key
+ (compression %compression)
+ (timeout 3600))
"Open an SSH session for HOST and return it. IDENTITY specifies the file
name of a private key to use for authenticating with the host. When USER,
PORT, or IDENTITY are #f, use default values or whatever '~/.ssh/config'
-specifies; otherwise use them. Throw an error on failure."
+specifies; otherwise use them.
+
+When HOST-KEY is true, it must be a string like \"ssh-ed25519 AAAAC3Nz…
+root@example.org\"; the server is authenticated and an error is raised if its
+host key is different from HOST-KEY.
+
+Install TIMEOUT as the maximum time in seconds after which a read or write
+operation on a channel of the returned session is considered as failing.
+
+Throw an error on failure."
(let ((session (make-session #:user user
#:identity identity
#:host host
#:timeout 10 ;seconds
;; #:log-verbosity 'protocol
+ ;; Prevent libssh from reading
+ ;; ~/.ssh/known_hosts when the caller provides
+ ;; a HOST-KEY to match against.
+ #:knownhosts (and host-key "/dev/null")
+
;; We need lightweight compression when
;; exchanging full archives.
#:compression compression
- #:compression-level 3)))
+ #:compression-level 3
+
+ ;; Speed up RPCs by creating sockets with
+ ;; TCP_NODELAY.
+ #:nodelay #t)))
;; Honor ~/.ssh/config.
(session-parse-config! session)
(match (connect! session)
('ok
+ (if host-key
+ ;; Make sure the server's key is what we expect.
+ (authenticate-server* session host-key)
+
+ ;; Authenticate against ~/.ssh/known_hosts.
+ (match (authenticate-server session)
+ ('ok #f)
+ (reason
+ (raise (formatted-message (G_ "failed to authenticate \
+server at '~a': ~a")
+ (session-get session 'host)
+ reason)))))
+
;; Use public key authentication, via the SSH agent if it's available.
(match (userauth-public-key/auto! session)
('success
+ (session-set! session 'timeout timeout)
session)
(x
- (disconnect! session)
- (raise (condition
- (&message
- (message (format #f (G_ "SSH authentication failed for '~a': ~a~%")
- host (get-error session)))))))))
+ (match (userauth-gssapi! session)
+ ('success
+ (session-set! session 'timeout timeout)
+ session)
+ (x
+ (disconnect! session)
+ (raise (condition
+ (&message
+ (message (format #f (G_ "SSH authentication failed for '~a': ~a~%")
+ host (get-error session)))))))))))
(x
;; Connection failed or timeout expired.
- (raise (condition
- (&message
- (message (format #f (G_ "SSH connection to '~a' failed: ~a~%")
- host (get-error session))))))))))
+ (raise (formatted-message (G_ "SSH connection to '~a' failed: ~a~%")
+ host (get-error session)))))))
(define* (remote-inferior session #:optional become-command)
"Return a remote inferior for the given SESSION. If BECOME-COMMAND is
(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))))))
+ (let ((status (channel-get-exit-status pipe)))
+ (close-port pipe)
+ (raise (formatted-message (G_ "remote command '~{~a~^ ~}' failed \
+with status ~a")
+ repl-command status))))
(port->inferior pipe)))
(define* (inferior-remote-eval exp session #:optional become-command)
;; <https://bugs.gnu.org/26976>.)
(close-inferior inferior)))))
+(define (remote-run exp session)
+ "Run EXP in a new process in SESSION and return a remote pipe.
+
+Unlike 'inferior-remote-eval', this is used for side effects and may
+communicate over stdout/stdin as it sees fit. EXP is typically a loop that
+processes data from stdin and/or sends data to stdout. The assumption is that
+EXP never returns or calls 'primitive-exit' when it's done."
+ (define pipe
+ (open-remote-pipe* session OPEN_BOTH
+ "guix" "repl" "-t" "machine"))
+
+ (match (read pipe)
+ (('repl-version _ ...)
+ #t)
+ ((? eof-object?)
+ (close-port pipe)
+ (raise (formatted-message
+ (G_ "failed to start 'guix repl' on '~a'")
+ (session-get session 'host)))))
+
+ ;; Disable buffering so 'guix repl' does not read more than what's really
+ ;; sent to itself.
+ (write '(setvbuf (current-input-port) 'none) pipe)
+ (force-output pipe)
+
+ ;; Read the reply and subsequent newline.
+ (read pipe) (get-u8 pipe)
+
+ (write exp pipe)
+ (force-output pipe)
+
+ ;; From now on, we stop following the inferior protocol.
+ pipe)
+
(define* (remote-daemon-channel session
#:optional
(socket-name
(_
(primitive-exit 1)))))))
- (open-remote-pipe* session OPEN_BOTH
- ;; Sort-of shell-quote REDIRECT.
- "guile" "-c"
- (object->string
- (object->string redirect))))
+ (remote-run redirect session))
(define* (connect-to-remote-daemon session
#:optional
(consume-input (current-input-port))
(list 'protocol-error (nix-protocol-error-message c))))
(with-store store
+ (write '(importing)) ;we're ready
+ (force-output)
+
(setvbuf (current-input-port) 'none)
(import-paths store (current-input-port))
'(success))))
(lambda args
- (cons 'error args))))))
+ (cons 'error args))))
+ (primitive-exit 0)))
- (open-remote-pipe session
- (string-join
- `("guile" "-c"
- ,(object->string (object->string import))))
- OPEN_BOTH))
+ (remote-run import session))
(define* (store-export-channel session files
#:key recursive?)
;; remote store.
(define export
`(begin
- (eval-when (load expand eval)
- (unless (resolve-module '(guix) #:ensure #f)
- (write `(module-error))
- (exit 7)))
-
(use-modules (guix) (srfi srfi-1)
(srfi srfi-26) (srfi srfi-34))
(guard (c ((nix-connection-error? c)
(write `(connection-error ,(nix-connection-error-file c)
- ,(nix-connection-error-code c))))
+ ,(nix-connection-error-code c)))
+ (primitive-exit 1))
((nix-protocol-error? c)
(write `(protocol-error ,(nix-protocol-error-status c)
- ,(nix-protocol-error-message c))))
+ ,(nix-protocol-error-message c)))
+ (primitive-exit 2))
(else
- (write `(exception))))
+ (write `(exception))
+ (primitive-exit 3)))
(with-store store
(let* ((files ',files)
(invalid (remove (cut valid-path? store <>)
(setvbuf (current-output-port) 'none)
(export-paths store files (current-output-port)
- #:recursive? ,recursive?))))))
+ #:recursive? ,recursive?)
+ (primitive-exit 0))))))
- (open-remote-input-pipe session
- (string-join
- `("guile" "-c"
- ,(object->string
- (object->string export))))))
+ (remote-run export session))
(define (remote-system session)
"Return the system type as expected by Nix, usually ARCHITECTURE-KERNEL, of
session
become-command))
+(define (prepare-to-send store host log-port items)
+ "Notify the user that we're about to send ITEMS to HOST. Return three
+values allowing 'notify-send-progress' to track the state of this transfer."
+ (let* ((count (length items))
+ (sizes (fold (lambda (item result)
+ (vhash-cons item
+ (path-info-nar-size
+ (query-path-info store item))
+ result))
+ vlist-null
+ items))
+ (total (vlist-fold (lambda (pair result)
+ (match pair
+ ((_ . size) (+ size result))))
+ 0
+ sizes)))
+ (info (N_ "sending ~a store item (~h MiB) to '~a'...~%"
+ "sending ~a store items (~h MiB) to '~a'...~%" count)
+ count
+ (inexact->exact (round (/ total (expt 2. 20))))
+ host)
+
+ (values log-port sizes total 0)))
+
+(define (notify-transfer-progress item port sizes total sent)
+ "Notify the user that we've already transferred SENT bytes out of TOTAL.
+Use SIZES to determine the size of ITEM, which is about to be sent."
+ (define (display-bar %)
+ (erase-current-line port)
+ (format port "~3@a% ~a"
+ (inexact->exact (round (* 100. (/ sent total))))
+ (progress-bar % (- (max (current-terminal-columns) 5) 5)))
+ (force-output port))
+
+ (unless (zero? total)
+ (let ((% (* 100. (/ sent total))))
+ (match (vhash-assoc item sizes)
+ (#f
+ (display-bar %)
+ (values port sizes total sent))
+ ((_ . size)
+ (display-bar %)
+ (values port sizes total (+ sent size)))))))
+
+(define (notify-transfer-completion port . args)
+ "Notify the user that the transfer has completed."
+ (apply notify-transfer-progress "" port args) ;display the 100% progress bar
+ (erase-current-line port)
+ (force-output port))
+
(define* (send-files local files remote
#:key
recursive?
(remove (cut valid-path? store <>)
',files)))
session))
- (count (length missing))
- (sizes (map (lambda (item)
- (path-info-nar-size (query-path-info local item)))
- missing))
- (port (store-import-channel session)))
- (format log-port (N_ "sending ~a store item (~h MiB) to '~a'...~%"
- "sending ~a store items (~h MiB) to '~a'...~%" count)
- count
- (inexact->exact (round (/ (reduce + 0 sizes) (expt 2. 20))))
- (session-get session 'host))
+ (port (store-import-channel session))
+ (host (session-get session 'host)))
+ ;; Make sure everything alright on the remote side.
+ (match (read port)
+ (('importing)
+ #t)
+ (sexp
+ (handle-import/export-channel-error sexp remote)))
;; Send MISSING in topological order.
- (export-paths local missing port)
+ (let ((tty? (isatty? log-port)))
+ (export-paths local missing port
+ #:start (cut prepare-to-send local host log-port <>)
+ #:progress (if tty? notify-transfer-progress (const #f))
+ #:finish (if tty? notify-transfer-completion (const #f))))
;; Tell the remote process that we're done. (In theory the end-of-archive
;; mark of 'export-paths' would be enough, but in practice it's not.)
(&message
(message (format #f fmt args ...))))))))
+(define (handle-import/export-channel-error sexp remote)
+ "Report an error corresponding to SEXP, the EOF object or an sexp read from
+REMOTE."
+ (match sexp
+ ((? eof-object?)
+ (report-guile-error (remote-store-host remote)))
+ (('connection-error file code . _)
+ (raise-error (G_ "failed to connect to '~A' on remote host '~A': ~a")
+ file (remote-store-host remote) (strerror code)))
+ (('invalid-items items . _)
+ (raise-error (N_ "no such item on remote host '~A':~{ ~a~}"
+ "no such items on remote host '~A':~{ ~a~}"
+ (length items))
+ (remote-store-host remote) items))
+ (('protocol-error status message . _)
+ (raise-error (G_ "protocol error on remote host '~A': ~a")
+ (remote-store-host remote) message))
+ (_
+ (raise-error (G_ "failed to retrieve store items from '~a'")
+ (remote-store-host remote)))))
+
(define* (retrieve-files* files remote
#:key recursive? (log-port (current-error-port))
(import (const #f)))
(import port))
(lambda ()
(close-port port))))
- ((? eof-object?)
- (report-guile-error (remote-store-host remote)))
- (('module-error . _)
- (report-module-error (remote-store-host remote)))
- (('connection-error file code . _)
- (raise-error (G_ "failed to connect to '~A' on remote host '~A': ~a")
- file (remote-store-host remote) (strerror code)))
- (('invalid-items items . _)
- (raise-error (N_ "no such item on remote host '~A':~{ ~a~}"
- "no such items on remote host '~A':~{ ~a~}"
- (length items))
- (remote-store-host remote) items))
- (('protocol-error status message . _)
- (raise-error (G_ "protocol error on remote host '~A': ~a")
- (remote-store-host remote) message))
- (_
- (raise-error (G_ "failed to retrieve store items from '~a'")
- (remote-store-host remote))))))
+ (sexp
+ (handle-import/export-channel-error sexp remote)))))
(define* (retrieve-files local files remote
#:key recursive? (log-port (current-error-port)))
check.")
host)))
-(define (report-module-error host)
- "Report an error about missing Guix modules on HOST."
- ;; TRANSLATORS: Leave "Guile" untranslated.
- (raise-error (G_ "Guile modules not found on remote host '~A'") host
- (=> (G_ "Make sure @code{GUILE_LOAD_PATH} includes Guix'
-own module directory. Run @command{ssh ~A env | grep GUILE_LOAD_PATH} to
-check.")
- host)))
+(define (report-inferior-exception exception host)
+ "Report EXCEPTION, an &inferior-exception that occurred on HOST."
+ (raise-error (G_ "exception occurred on remote host '~A': ~s")
+ host (inferior-exception-arguments exception)))
;;; ssh.scm ends here
HCoop / jackhill / guix / guix.git / blobdiff