[bug#41018] [PATCH] gnu: Add AutoSSH service.

[bug#41018] [PATCH] gnu: Add AutoSSH service.

[pinoaffe]

* doc/guix.texi: Add documentation.
* gnu/services/ssh.scm (<autossh-configuration>): New record type.
  (mpd-service-type): New service type.
---
 doc/guix.texi        |  75 +++++++++++++++++++++++++++++
 gnu/services/ssh.scm | 109 ++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 183 insertions(+), 1 deletion(-)

diff --git a/doc/guix.texi b/doc/guix.texi
index c571010bc8..f88859c584 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -78,6 +78,7 @@ Copyright @copyright{} 2020 Jack Hill@*
 Copyright @copyright{} 2020 Naga Malleswari@*
 Copyright @copyright{} 2020 Brice Waegeneire@*
 Copyright @copyright{} 2020 R Veera Kumar@*
+Copyright @copyright{} 2020 pinoaffe@*
 
 Permission is granted to copy, distribute and/or modify this document
 under the terms of the GNU Free Documentation License, Version 1.3 or
@@ -14378,6 +14379,80 @@ Whether to enable password-based authentication.
 @end table
 @end deftp
 
+@deffn {Scheme Procedure} autossh-service [@var{config}]
+Run the AutoSSH service with the given @var{config},
+a @code{<autossh-configuration>} object.
+
+AutoSSH is a program that runs a copy of @code{ssh} and monitors it,
+restarting it as necessary should it die or stop passing traffic.
+AutoSSH can be run manually from the commandline by passing arguments
+to the binary @code{autossh} from the package @code{autossh},
+but it can also be run as a guix service. This latter usecase is documented here.
+
+AutoSSH can be used to forward local traffic to a remote machine using an SSH tunnel,
+and it respects the @file{~/.ssh/config} of the user it is run as.
+
+For example, to specify a service running autossh as the user @code{pino}
+and forwarding all local connections to port @code{8081} to @code{remote:8081}
+using an SSH tunnel, add this call to the operating system's @code{services} field:
+
+@lisp
+(autossh (autossh-configuration
+          (user "pino")
+          (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
+@end lisp
+@end deffn
+
+@deftp {Data Type} autossh-configuration
+This data type represents the configuration of an AutoSSH service.
+
+@table @asis
+
+@item @code{user} (default @code{"autossh"})
+The user as which the AutoSSH service is to be run.
+This assumes that the specified user exists.
+
+@item @code{poll} (default @code{600})
+Specifies the connection poll time in seconds.
+
+@item @code{first-poll} (default @code{#f})
+Specifies how long autossh waits before the first connection test in seconds.
+After this first test, polling is resumed at the pace defined in @code{poll}.
+When set to @code{#f}, the first poll is not treated specially and
+will also use the connection poll specified in @code{poll}
+
+@item @code{gate-time} (default @code{30})
+Specifies (in seconds) how long an SSH connection must be active
+before it is considered successful.
+
+@item @code{log-level} (default @code{1})
+The log level, corresponding to the levels used by syslog
+(so @code{0} is the most silent while @code{7} is the chattiest.)
+
+@item @code{max-start} (default @code{#f})
+The maximum number of times SSH may be (re)started before AutoSSH exits.
+When set to @code{#f}, no maximum is configured and AutoSSH may restart indefinitely.
+
+@item @code{message} (default @code{""})
+The message to append to the echo message sent when testing connections.
+
+@item @code{port} (default @code{"0"})
+The ports used for monitoring the connection. When set to @code{"0"},
+monitoring is disabled. When set to @code{"n"} where @code{n} is a positive integer,
+ports @code{n} and @code{n+1} are used for monitoring the connection, such that
+port @code{n} is the base monitoring port and @code{n+1} is the echo port.
+When set to @code{"n:m"} where @code{n} and @code{m} are positive integers,
+the ports @code{n} and @code{n+1} are used for monitoring the connection, such
+that port @code{n} is the base monitoring port and @code{m} is the echo port.
+
+@item @code{ssh-options} (default @code{'()})
+The list of commandline arguments to pass to ssh when it is run.
+Options @code{-f} and @code{-M ....} are reserved for AutoSSH
+and may cause undefined behaviour.
+
+@end table
+@end deftp
+
 @defvr {Scheme Variable} %facebook-host-aliases
 This variable contains a string for use in @file{/etc/hosts}
 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}).  Each
diff --git a/gnu/services/ssh.scm b/gnu/services/ssh.scm
index d2dbb8f80d..ec0150b3a2 100644
--- a/gnu/services/ssh.scm
+++ b/gnu/services/ssh.scm
@@ -4,6 +4,7 @@
 ;;; Copyright © 2016 Julien Lepiller <julien@lepiller.eu>
 ;;; Copyright © 2017 Clément Lassieur <clement@lassieur.org>
 ;;; Copyright © 2019 Ricardo Wurmus <rekado@elephly.net>
+;;; Copyright © 2020 pinoaffe <pinoaffe@airmail.cc>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -45,7 +46,12 @@
             dropbear-configuration
             dropbear-configuration?
             dropbear-service-type
-            dropbear-service))
+            dropbear-service
+
+            autossh-configuration
+            autossh-configuration?
+            autossh-service-type
+            autossh-service))
 
 ;;; Commentary:
 ;;;
@@ -628,4 +634,105 @@ daemon} with the given @var{config}, a @code{<dropbear-configuration>}
 object."
   (service dropbear-service-type config))
 
+\f
+;;;
+;;; AutoSSH.
+;;;
+
+
+(define-record-type* <autossh-configuration>
+  autossh-configuration make-autossh-configuration
+  autossh-configuration?
+  (user            autossh-configuration-user
+                   (default "autossh"))
+  (poll            autossh-configuration-poll
+                   (default 600))
+  (first-poll      autossh-configuration-first-poll
+                   (default #f))
+  (gate-time       autossh-configuration-gate-time
+                   (default 30))
+  (log-level       autossh-configuration-log-level
+                   (default 1))
+  (max-start       autossh-configuration-max-start
+                   (default #f))
+  (message         autossh-configuration-message
+                   (default ""))
+  (port            autossh-configuration-port
+                   (default "0"))
+  (ssh-options     autossh-configuration-ssh-options
+                   (default '())))
+
+(define (autossh-file-name config file)
+  "Return a path in /var/run/autossh/ that is writable
+   by @code{user} from @code{config}."
+  (string-append "/var/run/autossh/"
+                 (autossh-configuration-user config)
+                 "/" file))
+
+(define (autossh-shepherd-service config)
+  (shepherd-service
+   (documentation "Automatically set up ssh connections (and keep them alive).")
+   (provision '(autossh))
+   (start #~(make-forkexec-constructor
+             (list #$(file-append autossh "/bin/autossh")
+                   #$@(autossh-configuration-ssh-options config))
+             #:user #$(autossh-configuration-user config)
+             #:group (passwd:gid (getpw #$(autossh-configuration-user config)))
+             #:pid-file #$(autossh-file-name config "pid")
+             #:log-file #$(autossh-file-name config "log")
+             #:environment-variables
+             '(#$(string-append "AUTOSSH_PIDFILE="
+                                (autossh-file-name config "pid"))
+               #$(string-append "AUTOSSH_LOGFILE="
+                                (autossh-file-name config "log"))
+               #$(string-append "AUTOSSH_POLL="
+                                (number->string
+                                 (autossh-configuration-poll config)))
+               #$(string-append "AUTOSSH_FIRST_POLL="
+                                (number->string
+                                 (or
+                                  (autossh-configuration-first-poll config)
+                                  (autossh-configuration-poll config))))
+               #$(string-append "AUTOSSH_GATETIME="
+                                (number->string
+                                 (autossh-configuration-gate-time config)))
+               #$(string-append "AUTOSSH_LOGLEVEL="
+                                (number->string
+                                 (autossh-configuration-log-level config)))
+               #$(string-append "AUTOSSH_MAXSTART="
+                                (number->string
+                                 (or (autossh-configuration-max-start config)
+                                     -1)))
+               #$(string-append "AUTOSSH_MESSAGE="
+                                (autossh-configuration-message config))
+               #$(string-append "AUTOSSH_PORT="
+                                (autossh-configuration-port config)))))
+   (stop #~(make-kill-destructor))))
+
+(define (autossh-service-activation config)
+  (with-imported-modules '((guix build utils))
+    #~(begin
+        (use-modules (guix build utils))
+        (define %user
+          (getpw #$(autossh-configuration-user config)))
+        (let ((directory #$(autossh-file-name config "")))
+          (mkdir-p directory)
+          (chown directory (passwd:uid %user) (passwd:gid %user))))))
+
+(define autossh-service-type
+  (service-type
+   (name 'autossh)
+   (description "Automatically set up ssh connections (and keep them alive).")
+   (extensions
+    (list (service-extension shepherd-root-service-type
+                             (compose list autossh-shepherd-service))
+          (service-extension activation-service-type
+                             autossh-service-activation)))
+   (default-value (autossh-configuration))))
+
+(define* (autossh-service #:optional (config (autossh-configuration)))
+  "Run autossh with the given @var{config}, a @code{<autossh-configuration>}
+object."
+  (service autossh-service-type config))
+
 ;;; ssh.scm ends here
-- 
2.26.2

[bug#41018] [PATCH] gnu: Add AutoSSH service.

[Oleg Pykhalov]

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Hi,

Thank you for the patch!

pinoaffe <pinoaffe@airmail.cc> writes:

> * doc/guix.texi: Add documentation.
> * gnu/services/ssh.scm (<autossh-configuration>): New record type.
>   (mpd-service-type): New service type.
> ---
>  doc/guix.texi        |  75 +++++++++++++++++++++++++++++
>  gnu/services/ssh.scm | 109 ++++++++++++++++++++++++++++++++++++++++++-
>  2 files changed, 183 insertions(+), 1 deletion(-)
>
> diff --git a/doc/guix.texi b/doc/guix.texi
> index c571010bc8..f88859c584 100644
> --- a/doc/guix.texi
> +++ b/doc/guix.texi

[…]

> +@lisp
> +(autossh (autossh-configuration
> +          (user "pino")
> +          (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
> +@end lisp
> +@end deffn

--8<---------------cut here---------------start------------->8---
(service autossh-service-type
         (autossh-configuration
          (user "pino")
          (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
--8<---------------cut here---------------end--------------->8---

[…]

> diff --git a/gnu/services/ssh.scm b/gnu/services/ssh.scm
> index d2dbb8f80d..ec0150b3a2 100644
> --- a/gnu/services/ssh.scm
> +++ b/gnu/services/ssh.scm

[…]

> +(define (autossh-service-activation config)
> +  (with-imported-modules '((guix build utils))
> +    #~(begin
> +        (use-modules (guix build utils))
> +        (define %user
> +          (getpw #$(autossh-configuration-user config)))
> +        (let ((directory #$(autossh-file-name config "")))
> +          (mkdir-p directory)
> +          (chown directory (passwd:uid %user) (passwd:gid %user))))))

I cannot start the service in a testing vm because of log file is owner
by root.  The following fixes this.


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diff --git a/gnu/services/ssh.scm b/gnu/services/ssh.scm
index ec0150b3a2..c111437b1a 100644
--- a/gnu/services/ssh.scm
+++ b/gnu/services/ssh.scm
@@ -715,9 +715,12 @@ object."
         (use-modules (guix build utils))
         (define %user
           (getpw #$(autossh-configuration-user config)))
-        (let ((directory #$(autossh-file-name config "")))
+        (let* ((directory #$(autossh-file-name config ""))
+               (log (string-append directory "/log")))
           (mkdir-p directory)
-          (chown directory (passwd:uid %user) (passwd:gid %user))))))
+          (chown directory (passwd:uid %user) (passwd:gid %user))
+          (call-with-output-file log (const #t))
+          (chown log (passwd:uid %user) (passwd:gid %user))))))
 
 (define autossh-service-type
   (service-type

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Also, why don't you put the log in /var/log directory?

Oleg.

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[bug#41018] [PATCH] gnu: Add AutoSSH service.

[pinoaffe]

> I cannot start the service in a testing vm because of log file is
> owner by root.  The following fixes this.
Thanks, I'll submit a modified patch

> Also, why don't you put the log in /var/log directory?
No particular reason, I simply replicated behavior I saw in some other
services. Should I change this?

[bug#41018] [PATCH] gnu: Add AutoSSH service.

[Oleg Pykhalov]

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pinoaffe <pinoaffe@airmail.cc> writes:

>> I cannot start the service in a testing vm because of log file is
>> owner by root.  The following fixes this.
> Thanks, I'll submit a modified patch

OK, then I could push it to master.

>> Also, why don't you put the log in /var/log directory?
> No particular reason, I simply replicated behavior I saw in some other
> services. Should I change this?

Depending on how much those logs are useful.  I don't know.  I'm OK with
either /var/run or /var/log, but /var/run will be removed after reboot.

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[bug#41018] [PATCH v2] gnu: Add AutoSSH service.

[pinoaffe]

* doc/guix.texi: Add documentation.
* gnu/services/ssh.scm (<autossh-configuration>): New record type.
  (mpd-service-type): New service type.
---
 doc/guix.texi        |  75 +++++++++++++++++++++++++++++
 gnu/services/ssh.scm | 112 ++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 186 insertions(+), 1 deletion(-)

diff --git a/doc/guix.texi b/doc/guix.texi
index c571010bc8..f88859c584 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -78,6 +78,7 @@ Copyright @copyright{} 2020 Jack Hill@*
 Copyright @copyright{} 2020 Naga Malleswari@*
 Copyright @copyright{} 2020 Brice Waegeneire@*
 Copyright @copyright{} 2020 R Veera Kumar@*
+Copyright @copyright{} 2020 pinoaffe@*
 
 Permission is granted to copy, distribute and/or modify this document
 under the terms of the GNU Free Documentation License, Version 1.3 or
@@ -14378,6 +14379,80 @@ Whether to enable password-based authentication.
 @end table
 @end deftp
 
+@deffn {Scheme Procedure} autossh-service [@var{config}]
+Run the AutoSSH service with the given @var{config},
+a @code{<autossh-configuration>} object.
+
+AutoSSH is a program that runs a copy of @code{ssh} and monitors it,
+restarting it as necessary should it die or stop passing traffic.
+AutoSSH can be run manually from the commandline by passing arguments
+to the binary @code{autossh} from the package @code{autossh},
+but it can also be run as a guix service. This latter usecase is documented here.
+
+AutoSSH can be used to forward local traffic to a remote machine using an SSH tunnel,
+and it respects the @file{~/.ssh/config} of the user it is run as.
+
+For example, to specify a service running autossh as the user @code{pino}
+and forwarding all local connections to port @code{8081} to @code{remote:8081}
+using an SSH tunnel, add this call to the operating system's @code{services} field:
+
+@lisp
+(autossh (autossh-configuration
+          (user "pino")
+          (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
+@end lisp
+@end deffn
+
+@deftp {Data Type} autossh-configuration
+This data type represents the configuration of an AutoSSH service.
+
+@table @asis
+
+@item @code{user} (default @code{"autossh"})
+The user as which the AutoSSH service is to be run.
+This assumes that the specified user exists.
+
+@item @code{poll} (default @code{600})
+Specifies the connection poll time in seconds.
+
+@item @code{first-poll} (default @code{#f})
+Specifies how long autossh waits before the first connection test in seconds.
+After this first test, polling is resumed at the pace defined in @code{poll}.
+When set to @code{#f}, the first poll is not treated specially and
+will also use the connection poll specified in @code{poll}
+
+@item @code{gate-time} (default @code{30})
+Specifies (in seconds) how long an SSH connection must be active
+before it is considered successful.
+
+@item @code{log-level} (default @code{1})
+The log level, corresponding to the levels used by syslog
+(so @code{0} is the most silent while @code{7} is the chattiest.)
+
+@item @code{max-start} (default @code{#f})
+The maximum number of times SSH may be (re)started before AutoSSH exits.
+When set to @code{#f}, no maximum is configured and AutoSSH may restart indefinitely.
+
+@item @code{message} (default @code{""})
+The message to append to the echo message sent when testing connections.
+
+@item @code{port} (default @code{"0"})
+The ports used for monitoring the connection. When set to @code{"0"},
+monitoring is disabled. When set to @code{"n"} where @code{n} is a positive integer,
+ports @code{n} and @code{n+1} are used for monitoring the connection, such that
+port @code{n} is the base monitoring port and @code{n+1} is the echo port.
+When set to @code{"n:m"} where @code{n} and @code{m} are positive integers,
+the ports @code{n} and @code{n+1} are used for monitoring the connection, such
+that port @code{n} is the base monitoring port and @code{m} is the echo port.
+
+@item @code{ssh-options} (default @code{'()})
+The list of commandline arguments to pass to ssh when it is run.
+Options @code{-f} and @code{-M ....} are reserved for AutoSSH
+and may cause undefined behaviour.
+
+@end table
+@end deftp
+
 @defvr {Scheme Variable} %facebook-host-aliases
 This variable contains a string for use in @file{/etc/hosts}
 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}).  Each
diff --git a/gnu/services/ssh.scm b/gnu/services/ssh.scm
index d2dbb8f80d..c111437b1a 100644
--- a/gnu/services/ssh.scm
+++ b/gnu/services/ssh.scm
@@ -4,6 +4,7 @@
 ;;; Copyright © 2016 Julien Lepiller <julien@lepiller.eu>
 ;;; Copyright © 2017 Clément Lassieur <clement@lassieur.org>
 ;;; Copyright © 2019 Ricardo Wurmus <rekado@elephly.net>
+;;; Copyright © 2020 pinoaffe <pinoaffe@airmail.cc>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -45,7 +46,12 @@
             dropbear-configuration
             dropbear-configuration?
             dropbear-service-type
-            dropbear-service))
+            dropbear-service
+
+            autossh-configuration
+            autossh-configuration?
+            autossh-service-type
+            autossh-service))
 
 ;;; Commentary:
 ;;;
@@ -628,4 +634,108 @@ daemon} with the given @var{

[bug#41018] [PATCH v2] gnu: Add AutoSSH service.

[Oleg Pykhalov]

[-- Attachment #1: Type: text/plain, Size: 1636 bytes --]

pinoaffe <pinoaffe@airmail.cc> writes:

> * doc/guix.texi: Add documentation.
> * gnu/services/ssh.scm (<autossh-configuration>): New record type.
>   (mpd-service-type): New service type.
> ---
>  doc/guix.texi        |  75 +++++++++++++++++++++++++++++
>  gnu/services/ssh.scm | 112 ++++++++++++++++++++++++++++++++++++++++++-
>  2 files changed, 186 insertions(+), 1 deletion(-)

[…]

>  ;;; Commentary:
>  ;;;
> @@ -628,4 +634,108 @@ daemon} with the given @var{

The patch is truncated on the hunk above.  Could you resend it, please?

Also not related, just for to notice you.  I receive delivery errors
from Gmail to your email address:
--8<---------------cut here---------------start------------->8---
** Delivery incomplete **

There was a temporary problem delivering your message to
pinoaffe@airmail.cc. Gmail will retry for 47 more hours. You'll be
notified if the delivery fails permanently.

The response from the remote server was:
454 4.7.0 TLS not available due to local problem

Reporting-MTA: dns; googlemail.com
Received-From-MTA: dns; go.wigust@gmail.com
Arrival-Date: Sun, 03 May 2020 08:52:44 -0700 (PDT)
X-Original-Message-ID: <871ro1kocb.fsf@gmail.com>

Final-Recipient: rfc822; pinoaffe@airmail.cc
Action: delayed
Status: 4.7.0
Remote-MTA: dns; mx1.cock.li. (37.120.193.125, the server for the domain airmail.cc.)
Diagnostic-Code: smtp; 454 4.7.0 TLS not available due to local problem
Last-Attempt-Date: Mon, 04 May 2020 09:44:16 -0700 (PDT)
Will-Retry-Until: Wed, 06 May 2020 08:52:44 -0700 (PDT)
--8<---------------cut here---------------end--------------->8---

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[bug#41018] [PATCH v2 try 2] gnu: Add AutoSSH service.

[pinoaffe]

* doc/guix.texi: Add documentation.
* gnu/services/ssh.scm (<autossh-configuration>): New record type.
  (mpd-service-type): New service type.
---
 doc/guix.texi        |  75 +++++++++++++++++++++++++++++
 gnu/services/ssh.scm | 112 ++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 186 insertions(+), 1 deletion(-)

diff --git a/doc/guix.texi b/doc/guix.texi
index c571010bc8..f88859c584 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -78,6 +78,7 @@ Copyright @copyright{} 2020 Jack Hill@*
 Copyright @copyright{} 2020 Naga Malleswari@*
 Copyright @copyright{} 2020 Brice Waegeneire@*
 Copyright @copyright{} 2020 R Veera Kumar@*
+Copyright @copyright{} 2020 pinoaffe@*
 
 Permission is granted to copy, distribute and/or modify this document
 under the terms of the GNU Free Documentation License, Version 1.3 or
@@ -14378,6 +14379,80 @@ Whether to enable password-based authentication.
 @end table
 @end deftp
 
+@deffn {Scheme Procedure} autossh-service [@var{config}]
+Run the AutoSSH service with the given @var{config},
+a @code{<autossh-configuration>} object.
+
+AutoSSH is a program that runs a copy of @code{ssh} and monitors it,
+restarting it as necessary should it die or stop passing traffic.
+AutoSSH can be run manually from the commandline by passing arguments
+to the binary @code{autossh} from the package @code{autossh},
+but it can also be run as a guix service. This latter usecase is documented here.
+
+AutoSSH can be used to forward local traffic to a remote machine using an SSH tunnel,
+and it respects the @file{~/.ssh/config} of the user it is run as.
+
+For example, to specify a service running autossh as the user @code{pino}
+and forwarding all local connections to port @code{8081} to @code{remote:8081}
+using an SSH tunnel, add this call to the operating system's @code{services} field:
+
+@lisp
+(autossh (autossh-configuration
+          (user "pino")
+          (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
+@end lisp
+@end deffn
+
+@deftp {Data Type} autossh-configuration
+This data type represents the configuration of an AutoSSH service.
+
+@table @asis
+
+@item @code{user} (default @code{"autossh"})
+The user as which the AutoSSH service is to be run.
+This assumes that the specified user exists.
+
+@item @code{poll} (default @code{600})
+Specifies the connection poll time in seconds.
+
+@item @code{first-poll} (default @code{#f})
+Specifies how long autossh waits before the first connection test in seconds.
+After this first test, polling is resumed at the pace defined in @code{poll}.
+When set to @code{#f}, the first poll is not treated specially and
+will also use the connection poll specified in @code{poll}
+
+@item @code{gate-time} (default @code{30})
+Specifies (in seconds) how long an SSH connection must be active
+before it is considered successful.
+
+@item @code{log-level} (default @code{1})
+The log level, corresponding to the levels used by syslog
+(so @code{0} is the most silent while @code{7} is the chattiest.)
+
+@item @code{max-start} (default @code{#f})
+The maximum number of times SSH may be (re)started before AutoSSH exits.
+When set to @code{#f}, no maximum is configured and AutoSSH may restart indefinitely.
+
+@item @code{message} (default @code{""})
+The message to append to the echo message sent when testing connections.
+
+@item @code{port} (default @code{"0"})
+The ports used for monitoring the connection. When set to @code{"0"},
+monitoring is disabled. When set to @code{"n"} where @code{n} is a positive integer,
+ports @code{n} and @code{n+1} are used for monitoring the connection, such that
+port @code{n} is the base monitoring port and @code{n+1} is the echo port.
+When set to @code{"n:m"} where @code{n} and @code{m} are positive integers,
+the ports @code{n} and @code{n+1} are used for monitoring the connection, such
+that port @code{n} is the base monitoring port and @code{m} is the echo port.
+
+@item @code{ssh-options} (default @code{'()})
+The list of commandline arguments to pass to ssh when it is run.
+Options @code{-f} and @code{-M ....} are reserved for AutoSSH
+and may cause undefined behaviour.
+
+@end table
+@end deftp
+
 @defvr {Scheme Variable} %facebook-host-aliases
 This variable contains a string for use in @file{/etc/hosts}
 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}).  Each
diff --git a/gnu/services/ssh.scm b/gnu/services/ssh.scm
index d2dbb8f80d..c111437b1a 100644
--- a/gnu/services/ssh.scm
+++ b/gnu/services/ssh.scm
@@ -4,6 +4,7 @@
 ;;; Copyright © 2016 Julien Lepiller <julien@lepiller.eu>
 ;;; Copyright © 2017 Clément Lassieur <clement@lassieur.org>
 ;;; Copyright © 2019 Ricardo Wurmus <rekado@elephly.net>
+;;; Copyright © 2020 pinoaffe <pinoaffe@airmail.cc>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -45,7 +46,12 @@
             dropbear-configuration
             dropbear-configuration?
             dropbear-service-type
-            dropbear-service))
+            dropbear-service
+
+            autossh-configuration
+            autossh-configuration?
+            autossh-service-type
+            autossh-service))
 
 ;;; Commentary:
 ;;;
@@ -628,4 +634,108 @@ daemon} with the given @var{config}, a @code{<dropbear-configuration>}
 object."
   (service dropbear-service-type config))
 
+\f
+;;;
+;;; AutoSSH.
+;;;
+
+
+(define-record-type* <autossh-configuration>
+  autossh-configuration make-autossh-configuration
+  autossh-configuration?
+  (user            autossh-configuration-user
+                   (default "autossh"))
+  (poll            autossh-configuration-poll
+                   (default 600))
+  (first-poll      autossh-configuration-first-poll
+                   (default #f))
+  (gate-time       autossh-configuration-gate-time
+                   (default 30))
+  (log-level       autossh-configuration-log-level
+                   (default 1))
+  (max-start       autossh-configuration-max-start
+                   (default #f))
+  (message         autossh-configuration-message
+                   (default ""))
+  (port            autossh-configuration-port
+                   (default "0"))
+  (ssh-options     autossh-configuration-ssh-options
+                   (default '())))
+
+(define (autossh-file-name config file)
+  "Return a path in /var/run/autossh/ that is writable
+   by @code{user} from @code{config}."
+  (string-append "/var/run/autossh/"
+                 (autossh-configuration-user config)
+                 "/" file))
+
+(define (autossh-shepherd-service config)
+  (shepherd-service
+   (documentation "Automatically set up ssh connections (and keep them alive).")
+   (provision '(autossh))
+   (start #~(make-forkexec-constructor
+             (list #$(file-append autossh "/bin/autossh")
+                   #$@(autossh-configuration-ssh-options config))
+             #:user #$(autossh-configuration-user config)
+             #:group (passwd:gid (getpw #$(autossh-configuration-user config)))
+             #:pid-file #$(autossh-file-name config "pid")
+             #:log-file #$(autossh-file-name config "log")
+             #:environment-variables
+             '(#$(string-append "AUTOSSH_PIDFILE="
+                                (autossh-file-name config "pid"))
+               #$(string-append "AUTOSSH_LOGFILE="
+                                (autossh-file-name config "log"))
+               #$(string-append "AUTOSSH_POLL="
+                                (number->string
+                                 (autossh-configuration-poll config)))
+               #$(string-append "AUTOSSH_FIRST_POLL="
+                                (number->string
+                                 (or
+                                  (autossh-configuration-first-poll config)
+                                  (autossh-configuration-poll config))))
+               #$(string-append "AUTOSSH_GATETIME="
+                                (number->string
+                                 (autossh-configuration-gate-time config)))
+               #$(string-append "AUTOSSH_LOGLEVEL="
+                                (number->string
+                                 (autossh-configuration-log-level config)))
+               #$(string-append "AUTOSSH_MAXSTART="
+                                (number->string
+                                 (or (autossh-configuration-max-start config)
+                                     -1)))
+               #$(string-append "AUTOSSH_MESSAGE="
+                                (autossh-configuration-message config))
+               #$(string-append "AUTOSSH_PORT="
+                                (autossh-configuration-port config)))))
+   (stop #~(make-kill-destructor))))
+
+(define (autossh-service-activation config)
+  (with-imported-modules '((guix build utils))
+    #~(begin
+        (use-modules (guix build utils))
+        (define %user
+          (getpw #$(autossh-configuration-user config)))
+        (let* ((directory #$(autossh-file-name config ""))
+               (log (string-append directory "/log")))
+          (mkdir-p directory)
+          (chown directory (passwd:uid %user) (passwd:gid %user))
+          (call-with-output-file log (const #t))
+          (chown log (passwd:uid %user) (passwd:gid %user))))))
+
+(define autossh-service-type
+  (service-type
+   (name 'autossh)
+   (description "Automatically set up ssh connections (and keep them alive).")
+   (extensions
+    (list (service-extension shepherd-root-service-type
+                             (compose list autossh-shepherd-service))
+          (service-extension activation-service-type
+                             autossh-service-activation)))
+   (default-value (autossh-configuration))))
+
+(define* (autossh-service #:optional (config (autossh-configuration)))
+  "Run autossh with the given @var{config}, a @code{<autossh-configuration>}
+object."
+  (service autossh-service-type config))
+
 ;;; ssh.scm ends here
-- 
2.26.2

[bug#41018] [PATCH v2 try 2] gnu: Add AutoSSH service.

[Oleg Pykhalov]

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pinoaffe <pinoaffe@airmail.cc> writes:

> * doc/guix.texi: Add documentation.
> * gnu/services/ssh.scm (<autossh-configuration>): New record type.
>   (mpd-service-type): New service type.
> ---

Not mpd-service-type. :-)  Changed to:
--8<---------------cut here---------------start------------->8---
gnu: Add AutoSSH service.

* gnu/services/ssh.scm (<autossh-configuration>): New record type.
(autossh-service-type): New variable.
(autossh-service-activation, autossh-file-name): New procedures.
* doc/guix.texi (Networking Services): Document this.
--8<---------------cut here---------------end--------------->8---

[…]

> +@lisp
> +(autossh (autossh-configuration
> +          (user "pino")
> +          (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
> +@end lisp
> +@end deffn
…
> +(define* (autossh-service #:optional (config (autossh-configuration)))
> +  "Run autossh with the given @var{config}, a @code{<autossh-configuration>}
> +object."
> +  (service autossh-service-type config))
> +

Procedures like this ‘autossh-service’ are deprecated. I removed it and
updated documentation accordingly.  Pushed to master with those changes.

Oleg.

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