aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorLudovic Courtès <ludo@gnu.org>2020-09-27 15:14:36 +0200
committerLudovic Courtès <ludo@gnu.org>2020-09-29 21:56:27 +0200
commit37283f9f3e0130e262e0e4e0dc4b260471bc485b (patch)
tree31f636067e8795c13bb34d8ac038053e3bd9c4f3
parentd367a7f3d00de20d5c6a88123297f878b3044fee (diff)
downloadguix-37283f9f3e0130e262e0e4e0dc4b260471bc485b.tar
guix-37283f9f3e0130e262e0e4e0dc4b260471bc485b.tar.gz
services: hurd-vm: Initialize the guest's SSH/Guix keys at activation time.
* gnu/services/virtualization.scm (initialize-hurd-vm-substitutes) (hurd-vm-activation): New procedures. (hurd-vm-service-type)[extensions]: Add ACTIVATION-SERVICE-TYPE extension. * doc/guix.texi (Transparent Emulation with QEMU): Mention GNU/Hurd. (The Hurd in a Virtual Machine): Explain which files are automatically installed and mention offloading.
-rw-r--r--doc/guix.texi33
-rw-r--r--gnu/services/virtualization.scm67
2 files changed, 96 insertions, 4 deletions
diff --git a/doc/guix.texi b/doc/guix.texi
index e6f04e1413..ff2e582347 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -25445,6 +25445,8 @@ emulation of program binaries built for different architectures---e.g.,
it allows you to transparently execute an ARMv7 program on an x86_64
machine. It achieves this by combining the @uref{https://www.qemu.org,
QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
+This feature only allows you to emulate GNU/Linux on a different
+architecture, but see below for GNU/Hurd support.
@defvr {Scheme Variable} qemu-binfmt-service-type
This is the type of the QEMU/binfmt service for transparent emulation.
@@ -25647,10 +25649,11 @@ If the @file{/etc/childhurd} directory does not exist, the
@code{secret-service} running in the Childhurd will be sent an empty
list of secrets.
-Typical use to populate @file{"/etc/childhurd"} with a tree of
-non-volatile secrets, like so
+By default, the service automatically populates @file{/etc/childhurd}
+with the following non-volatile secrets, unless they already exist:
@example
+/etc/childhurd/etc/guix/acl
/etc/childhurd/etc/guix/signing-key.pub
/etc/childhurd/etc/guix/signing-key.sec
/etc/childhurd/etc/ssh/ssh_host_ed25519_key
@@ -25659,8 +25662,32 @@ non-volatile secrets, like so
/etc/childhurd/etc/ssh/ssh_host_ecdsa_key.pub
@end example
-to be sent to the Childhurd, including permissions.
+These files are automatically sent to the guest Hurd VM when it boots,
+including permissions.
+@cindex childhurd, offloading
+@cindex Hurd, offloading
+Having these files in place means that only a couple of things are
+missing to allow the host to offload @code{i586-gnu} builds to the
+childhurd:
+
+@enumerate
+@item
+Authorizing the childhurd's key on the host so that the host accepts
+build results coming from the childhurd, which can be done like so:
+
+@example
+guix archive --authorize < \
+ /etc/childhurd/etc/guix/signing-key.pub
+@end example
+
+@item
+Adding the childhurd to @file{/etc/guix/machines.scm} (@pxref{Daemon
+Offload Setup}).
+@end enumerate
+
+We're working towards making that happen automatically---get in touch
+with us at @email{guix-devel@@gnu.org} to discuss it!
@end table
@end deftp
diff --git a/gnu/services/virtualization.scm b/gnu/services/virtualization.scm
index b84203ad18..c639fa3741 100644
--- a/gnu/services/virtualization.scm
+++ b/gnu/services/virtualization.scm
@@ -23,6 +23,7 @@
#:use-module (gnu bootloader grub)
#:use-module (gnu image)
#:use-module (gnu packages admin)
+ #:use-module (gnu packages package-management)
#:use-module (gnu packages ssh)
#:use-module (gnu packages virtualization)
#:use-module (gnu services base)
@@ -992,13 +993,77 @@ is added to the OS specified in CONFIG."
(shell (file-append shadow "/sbin/nologin"))
(system? #t))))
+(define (initialize-hurd-vm-substitutes)
+ "Initialize the Hurd VM's key pair and ACL and store it on the host."
+ (define run
+ (with-imported-modules '((guix build utils))
+ #~(begin
+ (use-modules (guix build utils)
+ (ice-9 match))
+
+ (define host-key
+ "/etc/guix/signing-key.pub")
+
+ (define host-acl
+ "/etc/guix/acl")
+
+ (match (command-line)
+ ((_ guest-config-directory)
+ (setenv "GUIX_CONFIGURATION_DIRECTORY"
+ guest-config-directory)
+ (invoke #+(file-append guix "/bin/guix") "archive"
+ "--generate-key")
+
+ (when (file-exists? host-acl)
+ ;; Copy the host ACL.
+ (copy-file host-acl
+ (string-append guest-config-directory
+ "/acl")))
+
+ (when (file-exists? host-key)
+ ;; Add the host key to the childhurd's ACL.
+ (let ((key (open-fdes host-key O_RDONLY)))
+ (close-fdes 0)
+ (dup2 key 0)
+ (execl #+(file-append guix "/bin/guix")
+ "guix" "archive" "--authorize"))))))))
+
+ (program-file "initialize-hurd-vm-substitutes" run))
+
+(define (hurd-vm-activation config)
+ "Return a gexp to activate the Hurd VM according to CONFIG."
+ (with-imported-modules '((guix build utils))
+ #~(begin
+ (use-modules (guix build utils))
+
+ (define secret-directory
+ #$(hurd-vm-configuration-secret-root config))
+
+ (define ssh-directory
+ (string-append secret-directory "/etc/ssh"))
+
+ (define guix-directory
+ (string-append secret-directory "/etc/guix"))
+
+ (unless (file-exists? ssh-directory)
+ ;; Generate SSH host keys under SSH-DIRECTORY.
+ (mkdir-p ssh-directory)
+ (invoke #$(file-append openssh "/bin/ssh-keygen")
+ "-A" "-f" secret-directory))
+
+ (unless (file-exists? guix-directory)
+ (invoke #$(initialize-hurd-vm-substitutes)
+ guix-directory)))))
+
(define hurd-vm-service-type
(service-type
(name 'hurd-vm)
(extensions (list (service-extension shepherd-root-service-type
hurd-vm-shepherd-service)
(service-extension account-service-type
- (const %hurd-vm-accounts))))
+ (const %hurd-vm-accounts))
+ (service-extension activation-service-type
+ hurd-vm-activation)))
(default-value (hurd-vm-configuration))
(description
"Provide a virtual machine (VM) running GNU/Hurd, also known as a