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Fix date format in manual pages.
2017-06-03 19:27:30 +00:00
.Dd October 5, 2015
Rewrite init(8).
2015-07-24 00:24:49 +00:00
.Dt INIT 8
.Os
.Sh NAME
.Nm init
.Nd system initialization
.Sh SYNOPSIS
.Nm init
.Op Fl \-target Ns "=" Ns Ar init-target
Refactor kernel command line parsing.
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.Op Fl \-
.Op Ar chain-init ...
Rewrite init(8).
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.Sh DESCRIPTION
.Nm
is the first program run after system startup and is responsible for
initializing the operating system and starting the specified
.Ar init-target .
This is normally a login screen, a root shell, or a dedicated special purpose
program.
.Pp
The
.Xr kernel 7
starts the system in a temporary environment with a root filesystem
backed by system memory and extracts the
.Xr initrd 7
Correct manpage spacing per roff(7) convention. roff(7) dictates that "Each sentence should terminate at the end of an input line." Instead of doing this, Sortix manpages (incorrectly) used double-spaces to separate sentences. Additionally, fix a few small typos.
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into it.
The kernel runs the
Rewrite init(8).
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.Pa /sbin/init
Correct manpage spacing per roff(7) convention. roff(7) dictates that "Each sentence should terminate at the end of an input line." Instead of doing this, Sortix manpages (incorrectly) used double-spaces to separate sentences. Additionally, fix a few small typos.
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program of the system memory root filesystem as the first process.
If the system is on bootable cdrom, then the initrd will be a fully functional
system and
Rewrite init(8).
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.Nm
Correct manpage spacing per roff(7) convention. roff(7) dictates that "Each sentence should terminate at the end of an input line." Instead of doing this, Sortix manpages (incorrectly) used double-spaces to separate sentences. Additionally, fix a few small typos.
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will start a live environment or an operating system installer.
If the system is installed on a harddisk, then the initrd is a minimal system
made with
Rewrite init(8).
2015-07-24 00:24:49 +00:00
.Xr update-initrd 8
Correct manpage spacing per roff(7) convention. roff(7) dictates that "Each sentence should terminate at the end of an input line." Instead of doing this, Sortix manpages (incorrectly) used double-spaces to separate sentences. Additionally, fix a few small typos.
2017-02-15 21:56:28 +00:00
that will search for the actual root filesystem and chain init it.
The next stage init will recognize it as the intended system and complete the
system startup.
Rewrite init(8).
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.Ss Initialization Target
.Nm
first determines its target from the
.Fl \-target
option if specified or
.Pa /etc/init/target
Correct manpage spacing per roff(7) convention. roff(7) dictates that "Each sentence should terminate at the end of an input line." Instead of doing this, Sortix manpages (incorrectly) used double-spaces to separate sentences. Additionally, fix a few small typos.
2017-02-15 21:56:28 +00:00
otherwise.
Supported targets are:
Rewrite init(8).
2015-07-24 00:24:49 +00:00
.Pp
.Bl -tag -width "single-user" -compact -offset indent
Refactor init(8) chain-merge target and add merge target. The chain-merge target now invokes the /sysmerge init(8) with the merge target, which now mounts the mountpoints. This change allows having a /boot partition for the purpose of sysupgrade(8).
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.It Sy chain
Rewrite init(8).
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mount real root filesystem and run its
Refactor init(8) chain-merge target and add merge target. The chain-merge target now invokes the /sysmerge init(8) with the merge target, which now mounts the mountpoints. This change allows having a /boot partition for the purpose of sysupgrade(8).
2016-08-21 21:03:33 +00:00
.Nm .
.It Sy chain-merge
like
.Sy chain
but run
.Pa /sysmerge/sbin/init
with the
.Sy merge
target.
.It Sy merge
finish a
Add sysinstall(8), sysmerge(8), and sysupgrade(8).
2016-02-18 21:16:02 +00:00
.Xr sysmerge 8
Refactor init(8) chain-merge target and add merge target. The chain-merge target now invokes the /sysmerge init(8) with the merge target, which now mounts the mountpoints. This change allows having a /boot partition for the purpose of sysupgrade(8).
2016-08-21 21:03:33 +00:00
upgrade and then execute the real
.Nm
with its default target.
.It Sy multi-user
Rewrite init(8).
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boot to
Refactor init(8) chain-merge target and add merge target. The chain-merge target now invokes the /sysmerge init(8) with the merge target, which now mounts the mountpoints. This change allows having a /boot partition for the purpose of sysupgrade(8).
2016-08-21 21:03:33 +00:00
.Xr login 8 .
.It Sy single-user
boot to root shell without password (not secure).
.It Sy sysinstall
boot to operating system installer (not secure).
.It Sy sysupgrade
boot to operating system upgrader (not secure).
Rewrite init(8).
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.El
.Pp
It is a full system compromise if unauthenticated users are able to boot the
Correct manpage spacing per roff(7) convention. roff(7) dictates that "Each sentence should terminate at the end of an input line." Instead of doing this, Sortix manpages (incorrectly) used double-spaces to separate sentences. Additionally, fix a few small typos.
2017-02-15 21:56:28 +00:00
wrong target.
The kernel command line can specify the path to
.Nm
and its arguments.
Unprivileged users can change the kernel command line from the bootloader
command line if it hasn't been password protected.
Likewise unprivileged users can use their own replacement bootloader by booting
a portable device under their control if the firmware configuration has not been
Rewrite init(8).
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password protected.
.Ss Partition Creation
.Nm
will scan every block device for valid partition tables and create the
corresponding partition devices in
.Pa /dev .
.Ss Chain Initialization
Refactor init(8) chain-merge target and add merge target. The chain-merge target now invokes the /sysmerge init(8) with the merge target, which now mounts the mountpoints. This change allows having a /boot partition for the purpose of sysupgrade(8).
2016-08-21 21:03:33 +00:00
The
.Sy chain
target mounts the root filesystem as in
Rewrite init(8).
2015-07-24 00:24:49 +00:00
.Pa /etc/fstab
Add support for multiple mount points to init(8).
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(see
Refactor kernel command line parsing.
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.Xr fstab 5 )
and runs the next
Add support for multiple mount points to init(8).
2016-02-15 14:09:21 +00:00
.Nm
Correct manpage spacing per roff(7) convention. roff(7) dictates that "Each sentence should terminate at the end of an input line." Instead of doing this, Sortix manpages (incorrectly) used double-spaces to separate sentences. Additionally, fix a few small typos.
2017-02-15 21:56:28 +00:00
program.
This is used by
Add support for multiple mount points to init(8).
2016-02-15 14:09:21 +00:00
.Xr update-initrd 8
to make a bootstrap
.Xr initrd 7 .
Rewrite init(8).
2015-07-24 00:24:49 +00:00
.Pp
Add support for multiple mount points to init(8).
2016-02-15 14:09:21 +00:00
Every block device and partition is scanned to determine if it is the root
Correct manpage spacing per roff(7) convention. roff(7) dictates that "Each sentence should terminate at the end of an input line." Instead of doing this, Sortix manpages (incorrectly) used double-spaces to separate sentences. Additionally, fix a few small typos.
2017-02-15 21:56:28 +00:00
filesystem.
It is checked for consistency if necessary.
It is mounted at
Rewrite init(8).
2015-07-24 00:24:49 +00:00
.Pa /tmp/fs.XXXXXX
and the
.Pa /dev
filesystem directory is bound at
.Pa /tmp/fs.XXXXXX/dev .
.Pp
Finally the
.Pa /sbin/init
Refactor kernel command line parsing.
2017-02-25 22:25:53 +00:00
program (or
.Ar chain-init
if specified) of the target root filesystem is run inside a chroot.
Rewrite init(8).
2015-07-24 00:24:49 +00:00
.Ss Configuration
Once the
.Nm
of the real root filesystem runs, it will process basic configuration files and
apply them:
.Pp
.Bl -tag -width "/etc/videomode" -compact -offset indent
.It Pa /etc/hostname
set hostname (see
.Xr hostname 5 )
.It Pa /etc/kblayout
set keyboard layout (see
.Xr kblayout 5 )
.It Pa /etc/videomode
set graphics resolution (see
.Xr videomode 5 )
.El
Document that init(8) mounts the filesystems of fstab(5). Remove --help and --version in favor of the init(8) manual page.
2016-08-20 01:17:29 +00:00
.Ss Mountpoints
.Nm
mounts all the filesystems according to
.Xr fstab 5 .
Seed kernel entropy with randomness from the previous boot. The bootloader will now load the /boot/random.seed file if it exists, in which case the kernel will use it as the initial kernel entropy. The kernel warns if no random seed was loaded, unless the --no-random-seed option was given. This option is used for live environments that inherently have no prior secret state. The kernel initializes its entropy pool from the random seed as of the first things, so randomness is available very early on. init(8) will emit a fresh /boot/random.seed file on boot to avoid the same entropy being used twice. init(8) also writes out /boot/random.seed on system shutdown where the system has the most entropy. init(8) will warn if writing the file fails, except if /boot is a real-only filesystem, and keeping such state is impossible. The system administrator is then responsible for ensuring the bootloader somehow passes a fresh random seed on the next boot. /boot/random.seed must be owned by the root user and root group and must have file permissions 600 to avoid unprivileged users can read it. The file is passed to the kernel by the bootloader as a multiboot module with the command line --random-seed. If no random seed is loaded, the kernel attempts a poor quality fallback where it seeds the kernel arc4random(3) continuously with the current time. The timing variance may provide some effective entropy. There is no real kernel entropy gathering yet. The read of the CMOS real time clock is moved to an early point in the kernel boot, so the current time is available as fallback entropy. The kernel access of the random seed module is supposed to be infallible and happens before the kernel log is set up, but there is not yet a failsafe API for mapping single pages in the early kernel. sysupgrade(8) creates /boot/random.seed if it's absent as a temporary compatibility measure for people upgrading from the 1.0 release. The GRUB port will need to be upgraded with support for /boot/random.seed in the 10_sortix script. Installation with manual bootloader configuration will need to load the random seed with the --random-seed command line. With GRUB, this can be done with: module /boot/random.seed --random-seed
2016-08-20 00:27:33 +00:00
.Ss Random Seed
.Nm
will write 256 bytes of randomness to
.Pa /boot/random.seed ,
which serves as the initial entropy for the
.Xr kernel 7
Correct manpage spacing per roff(7) convention. roff(7) dictates that "Each sentence should terminate at the end of an input line." Instead of doing this, Sortix manpages (incorrectly) used double-spaces to separate sentences. Additionally, fix a few small typos.
2017-02-15 21:56:28 +00:00
on the next boot.
The file is also written on system shutdown where the system has the most
entropy.
Refactor init(8) chain-merge target and add merge target. The chain-merge target now invokes the /sysmerge init(8) with the merge target, which now mounts the mountpoints. This change allows having a /boot partition for the purpose of sysupgrade(8).
2016-08-21 21:03:33 +00:00
.Ss Merge
The
.Sy merge
target completes a delayed system upgrade by invoking the
.Xr sysmerge 8
at
.Pa /sysmerge/sbin/sysmerge
with the
.Ar --booting
Correct manpage spacing per roff(7) convention. roff(7) dictates that "Each sentence should terminate at the end of an input line." Instead of doing this, Sortix manpages (incorrectly) used double-spaces to separate sentences. Additionally, fix a few small typos.
2017-02-15 21:56:28 +00:00
option.
If the upgrade succeeds, the temporary
Refactor init(8) chain-merge target and add merge target. The chain-merge target now invokes the /sysmerge init(8) with the merge target, which now mounts the mountpoints. This change allows having a /boot partition for the purpose of sysupgrade(8).
2016-08-21 21:03:33 +00:00
.Nm
deinitializes the system and invokes the real (now upgraded)
.Nm
which will restart system initialization in the normal fashion.
Rewrite init(8).
2015-07-24 00:24:49 +00:00
.Ss Session
Finally
.Nm
Correct manpage spacing per roff(7) convention. roff(7) dictates that "Each sentence should terminate at the end of an input line." Instead of doing this, Sortix manpages (incorrectly) used double-spaces to separate sentences. Additionally, fix a few small typos.
2017-02-15 21:56:28 +00:00
will start the target program according to its initialization target.
This will be a login screen, a root shell, or something else.
If the process exits abnormally
Rewrite init(8).
2015-07-24 00:24:49 +00:00
.Nm
will automatically restart it.
.Nm
Correct manpage spacing per roff(7) convention. roff(7) dictates that "Each sentence should terminate at the end of an input line." Instead of doing this, Sortix manpages (incorrectly) used double-spaces to separate sentences. Additionally, fix a few small typos.
2017-02-15 21:56:28 +00:00
will exit with the same exit status as the process if it exits normally.
The kernel decides whether to power off, reboot or halt based on this exit
status.
Rewrite init(8).
2015-07-24 00:24:49 +00:00
.Sh ENVIRONMENT
.Nm
sets the following environment variables.
.Bl -tag -width "INIT_PID"
.It Ev HOME
root's home directory
.It Ev INIT_PID
.Nm Ns 's
process id
.It Ev LOGNAME
root
.It Ev PATH
.Pa /bin:/sbin
.It Ev SHELL
root's shell
.It Ev TERM
sortix
.It Ev USER
root
.El
.Sh FILES
Seed kernel entropy with randomness from the previous boot. The bootloader will now load the /boot/random.seed file if it exists, in which case the kernel will use it as the initial kernel entropy. The kernel warns if no random seed was loaded, unless the --no-random-seed option was given. This option is used for live environments that inherently have no prior secret state. The kernel initializes its entropy pool from the random seed as of the first things, so randomness is available very early on. init(8) will emit a fresh /boot/random.seed file on boot to avoid the same entropy being used twice. init(8) also writes out /boot/random.seed on system shutdown where the system has the most entropy. init(8) will warn if writing the file fails, except if /boot is a real-only filesystem, and keeping such state is impossible. The system administrator is then responsible for ensuring the bootloader somehow passes a fresh random seed on the next boot. /boot/random.seed must be owned by the root user and root group and must have file permissions 600 to avoid unprivileged users can read it. The file is passed to the kernel by the bootloader as a multiboot module with the command line --random-seed. If no random seed is loaded, the kernel attempts a poor quality fallback where it seeds the kernel arc4random(3) continuously with the current time. The timing variance may provide some effective entropy. There is no real kernel entropy gathering yet. The read of the CMOS real time clock is moved to an early point in the kernel boot, so the current time is available as fallback entropy. The kernel access of the random seed module is supposed to be infallible and happens before the kernel log is set up, but there is not yet a failsafe API for mapping single pages in the early kernel. sysupgrade(8) creates /boot/random.seed if it's absent as a temporary compatibility measure for people upgrading from the 1.0 release. The GRUB port will need to be upgraded with support for /boot/random.seed in the 10_sortix script. Installation with manual bootloader configuration will need to load the random seed with the --random-seed command line. With GRUB, this can be done with: module /boot/random.seed --random-seed
2016-08-20 00:27:33 +00:00
.Bl -tag -width "/boot/random.seed" -compact
.It Pa /boot/random.seed
initial kernel entropy
Rewrite init(8).
2015-07-24 00:24:49 +00:00
.It Pa /etc/init/target
default initialization target
.It Pa /etc/fstab
filesystem table (see
.Xr fstab 5 )
.It Pa /etc/hostname
hostname (see
.Xr hostname 5 )
.It Pa /etc/kblayout
keyboard layout (see
.Xr kblayout 5 )
.It Pa /etc/videomode
graphics resolution (see
.Xr videomode 5 )
.El
.Sh EXIT STATUS
.Nm
exits 0 if the kernel should power off, exits 1 if the kernel should reboot, or
Print an kernel error rather than panicing if init(8) exits abnormally. This avoids the misimpression that a kernel bug happened and it avoids clearing the screen of potentially useful information about an init(8) crash.
2017-05-21 20:20:28 +00:00
exits 2 if the boot failed and the kernel should halt with a complaint about an
.Nm
fatality.
Correct manpage spacing per roff(7) convention. roff(7) dictates that "Each sentence should terminate at the end of an input line." Instead of doing this, Sortix manpages (incorrectly) used double-spaces to separate sentences. Additionally, fix a few small typos.
2017-02-15 21:56:28 +00:00
Any other exit by the initial
Rewrite init(8).
2015-07-24 00:24:49 +00:00
.Nm
Print an kernel error rather than panicing if init(8) exits abnormally. This avoids the misimpression that a kernel bug happened and it avoids clearing the screen of potentially useful information about an init(8) crash.
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will cause the kernel to halt with a complaint about an unexpected exit code.
Rewrite init(8).
2015-07-24 00:24:49 +00:00
.Nm
exits with the same exit status as its target session if it terminates normally.
.Sh SEE ALSO
.Xr fstab 5 ,
.Xr hostname 5 ,
.Xr kblayout 5 ,
.Xr videomode 5 ,
.Xr initrd 7 ,
.Xr kernel 7 ,
.Xr login 8 ,
Add sysinstall(8), sysmerge(8), and sysupgrade(8).
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.Xr sysmerge 8 ,
Rewrite init(8).
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.Xr update-initrd 8