mmdebstrap/mmdebstrap

4726 lines
189 KiB
Perl
Executable file

#!/usr/bin/perl
#
# Copyright: 2018 Johannes Schauer <josch@mister-muffin.de>
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to
# deal in the Software without restriction, including without limitation the
# rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
# sell copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# The software is provided "as is", without warranty of any kind, express or
# implied, including but not limited to the warranties of merchantability,
# fitness for a particular purpose and noninfringement. In no event shall the
# authors or copyright holders be liable for any claim, damages or other
# liability, whether in an action of contract, tort or otherwise, arising
# from, out of or in connection with the software or the use or other dealings
# in the software.
use strict;
use warnings;
our $VERSION = '0.5.1';
use English;
use Getopt::Long;
use Pod::Usage;
use File::Copy;
use File::Path qw(make_path remove_tree);
use File::Temp qw(tempfile tempdir);
use File::Basename;
use Cwd qw(abs_path);
require "syscall.ph";
use Fcntl qw(S_IFCHR S_IFBLK FD_CLOEXEC F_GETFD F_SETFD);
use List::Util qw(any none);
use POSIX qw(SIGINT SIGHUP SIGPIPE SIGTERM SIG_BLOCK SIG_UNBLOCK);
use Carp;
use Term::ANSIColor;
use Socket;
# from sched.h
use constant {
CLONE_NEWNS => 0x20000,
CLONE_NEWUTS => 0x4000000,
CLONE_NEWIPC => 0x8000000,
CLONE_NEWUSER => 0x10000000,
CLONE_NEWPID => 0x20000000,
CLONE_NEWNET => 0x40000000,
};
# type codes:
# 0 -> normal file
# 1 -> hardlink
# 2 -> symlink
# 3 -> character special
# 4 -> block special
# 5 -> directory
my @devfiles = (
# filename mode type link target major minor
["./dev/", 0755, 5, '', undef, undef],
["./dev/console", 0666, 3, '', 5, 1],
["./dev/fd", 0777, 2, '/proc/self/fd', undef, undef],
["./dev/full", 0666, 3, '', 1, 7],
["./dev/null", 0666, 3, '', 1, 3],
["./dev/ptmx", 0666, 3, '', 5, 2],
["./dev/pts/", 0755, 5, '', undef, undef],
["./dev/random", 0666, 3, '', 1, 8],
["./dev/shm/", 0755, 5, '', undef, undef],
["./dev/stderr", 0777, 2, '/proc/self/fd/2', undef, undef],
["./dev/stdin", 0777, 2, '/proc/self/fd/0', undef, undef],
["./dev/stdout", 0777, 2, '/proc/self/fd/1', undef, undef],
["./dev/tty", 0666, 3, '', 5, 0],
["./dev/urandom", 0666, 3, '', 1, 9],
["./dev/zero", 0666, 3, '', 1, 5],
);
# verbosity levels:
# 0 -> print nothing
# 1 -> normal output and progress bars
# 2 -> verbose output
# 3 -> debug output
my $verbosity_level = 1;
my $is_covering = !!(eval 'Devel::Cover::get_coverage()');
sub debug {
if ($verbosity_level < 3) {
return;
}
my $msg = shift;
my ($package, $filename, $line) = caller;
$msg = "D: $PID $line $msg";
if (-t STDERR) {
$msg = colored($msg, 'clear');
}
print STDERR "$msg\n";
}
sub info {
if ($verbosity_level == 0) {
return;
}
my $msg = shift;
if ($verbosity_level >= 3) {
my ($package, $filename, $line) = caller;
$msg = "$PID $line $msg";
}
$msg = "I: $msg";
if (-t STDERR) {
$msg = colored($msg, 'green');
}
print STDERR "$msg\n";
}
sub warning {
if ($verbosity_level == 0) {
return;
}
my $msg = shift;
$msg = "W: $msg";
if (-t STDERR) {
$msg = colored($msg, 'bold yellow');
}
print STDERR "$msg\n";
}
sub error {
if ($verbosity_level == 0) {
return;
}
# if error() is called with the string from a previous error() that was
# caught inside an eval(), then the string will have a newline which we
# are stripping here
chomp(my $msg = shift);
$msg = "E: $msg";
if (-t STDERR) {
$msg = colored($msg, 'bold red');
}
if ($verbosity_level == 3) {
croak $msg; # produces a backtrace
} else {
die "$msg\n";
}
}
# check whether a directory is mounted by comparing the device number of the
# directory itself with its parent
sub is_mountpoint($) {
my $dir = shift;
if (!-e $dir) {
return 0;
}
my @a = stat "$dir/.";
my @b = stat "$dir/..";
# if the device number is different, then the directory must be mounted
if ($a[0] != $b[0]) {
return 1;
}
# if the inode number is the same, then the directory must be mounted
if ($a[1] == $b[1]) {
return 1;
}
return 0;
}
# tar cannot figure out the decompression program when receiving data on
# standard input, thus we do it ourselves. This is copied from tar's
# src/suffix.c
sub get_tar_compressor($) {
my $filename = shift;
if ($filename eq '-') {
return undef;
} elsif ($filename =~ /\.tar$/) {
return undef;
} elsif ($filename =~ /\.(gz|tgz|taz)$/) {
return ['gzip'];
} elsif ($filename =~ /\.(Z|taZ)$/) {
return ['compress'];
} elsif ($filename =~ /\.(bz2|tbz|tbz2|tz2)$/) {
return ['bzip2'];
} elsif ($filename =~ /\.lz$/) {
return ['lzip'];
} elsif ($filename =~ /\.(lzma|tlz)$/) {
return ['lzma'];
} elsif ($filename =~ /\.lzo$/) {
return ['lzop'];
} elsif ($filename =~ /\.lz4$/) {
return ['lz4'];
} elsif ($filename =~ /\.(xz|txz)$/) {
return ['xz', '--threads=0'];
} elsif ($filename =~ /\.zst$/) {
return ['zstd'];
}
return undef;
}
sub test_unshare($) {
my $verbose = shift;
if ($EFFECTIVE_USER_ID == 0) {
my $msg = "cannot use unshare mode when executing as root";
if ($verbose) {
warning $msg;
} else {
debug $msg;
}
return 0;
}
# arguments to syscalls have to be stored in their own variable or
# otherwise we will get "Modification of a read-only value attempted"
my $unshare_flags = CLONE_NEWUSER;
# we spawn a new per process because if unshare succeeds, we would
# otherwise have unshared the mmdebstrap process itself which we don't want
my $pid = fork() // error "fork() failed: $!";
if ($pid == 0) {
my $ret = syscall &SYS_unshare, $unshare_flags;
if ($ret == 0) {
exit 0;
} else {
my $msg = "unshare syscall failed: $!";
if ($verbose) {
warning $msg;
} else {
debug $msg;
}
exit 1;
}
}
waitpid($pid, 0);
if (($? >> 8) != 0) {
return 0;
}
# if newuidmap and newgidmap exist, the exit status will be 1 when
# executed without parameters
system "newuidmap 2>/dev/null";
if (($? >> 8) != 1) {
if (($? >> 8) == 127) {
my $msg = "cannot find newuidmap";
if ($verbose) {
warning $msg;
} else {
debug $msg;
}
} else {
my $msg = "newuidmap returned unknown exit status: $?";
if ($verbose) {
warning $msg;
} else {
debug $msg;
}
}
return 0;
}
system "newgidmap 2>/dev/null";
if (($? >> 8) != 1) {
if (($? >> 8) == 127) {
my $msg = "cannot find newgidmap";
if ($verbose) {
warning $msg;
} else {
debug $msg;
}
} else {
my $msg = "newgidmap returned unknown exit status: $?";
if ($verbose) {
warning $msg;
} else {
debug $msg;
}
}
return 0;
}
return 1;
}
sub read_subuid_subgid() {
my $username = getpwuid $<;
my ($subid, $num_subid, $fh, $n);
my @result = ();
if (!-e "/etc/subuid") {
warning "/etc/subuid doesn't exist";
return;
}
if (!-r "/etc/subuid") {
warning "/etc/subuid is not readable";
return;
}
open $fh, "<", "/etc/subuid"
or error "cannot open /etc/subuid for reading: $!";
while (my $line = <$fh>) {
($n, $subid, $num_subid) = split(/:/, $line, 3);
last if ($n eq $username);
}
close $fh;
push @result, ["u", 0, $subid, $num_subid];
if (scalar(@result) < 1) {
warning "/etc/subuid does not contain an entry for $username";
return;
}
if (scalar(@result) > 1) {
warning "/etc/subuid contains multiple entries for $username";
return;
}
open $fh, "<", "/etc/subgid"
or error "cannot open /etc/subgid for reading: $!";
while (my $line = <$fh>) {
($n, $subid, $num_subid) = split(/:/, $line, 3);
last if ($n eq $username);
}
close $fh;
push @result, ["g", 0, $subid, $num_subid];
if (scalar(@result) < 2) {
warning "/etc/subgid does not contain an entry for $username";
return;
}
if (scalar(@result) > 2) {
warning "/etc/subgid contains multiple entries for $username";
return;
}
return @result;
}
# This function spawns two child processes forming the following process tree
#
# A
# |
# fork()
# | \
# B C
# | |
# | fork()
# | | \
# | D E
# | | |
# |unshare()
# | close()
# | | |
# | | read()
# | | newuidmap(D)
# | | newgidmap(D)
# | | /
# | waitpid()
# | |
# | fork()
# | | \
# | F G
# | | |
# | | exec()
# | | /
# | waitpid()
# | /
# waitpid()
#
# To better refer to each individual part, we give each process a new
# identifier after calling fork(). Process A is the main process. After
# executing fork() we call the parent and child B and C, respectively. This
# first fork() is done because we do not want to modify A. B then remains
# waiting for its child C to finish. C calls fork() again, splitting into
# the parent D and its child E. In the parent D we call unshare() and close a
# pipe shared by D and E to signal to E that D is done with calling unshare().
# E notices this by using read() and follows up with executing the tools
# new[ug]idmap on D. E finishes and D continues with doing another fork().
# This is because when unsharing the PID namespace, we need a PID 1 to be kept
# alive or otherwise any child processes cannot fork() anymore themselves. So
# we keep F as PID 1 and finally call exec() in G.
sub get_unshare_cmd(&$) {
my $cmd = shift;
my $idmap = shift;
my $unshare_flags
= CLONE_NEWUSER | CLONE_NEWNS | CLONE_NEWPID | CLONE_NEWUTS
| CLONE_NEWIPC;
if (0) {
$unshare_flags |= CLONE_NEWNET;
}
# fork a new process and let the child get unshare()ed
# we don't want to unshare the parent process
my $gcpid = fork() // error "fork() failed: $!";
if ($gcpid == 0) {
# Create a pipe for the parent process to signal the child process that
# it is done with calling unshare() so that the child can go ahead
# setting up uid_map and gid_map.
pipe my $rfh, my $wfh;
# We have to do this dance with forking a process and then modifying
# the parent from the child because:
# - new[ug]idmap can only be called on a process id after that process
# has unshared the user namespace
# - a process looses its capabilities if it performs an execve() with
# nonzero user ids see the capabilities(7) man page for details.
# - a process that unshared the user namespace by default does not
# have the privileges to call new[ug]idmap on itself
#
# this also works the other way around (the child setting up a user
# namespace and being modified from the parent) but that way, the
# parent would have to stay around until the child exited (so a pid
# would be wasted). Additionally, that variant would require an
# additional pipe to let the parent signal the child that it is done
# with calling new[ug]idmap. The way it is done here, this signaling
# can instead be done by wait()-ing for the exit of the child.
my $ppid = $$;
my $cpid = fork() // error "fork() failed: $!";
if ($cpid == 0) {
# child
# Close the writing descriptor at our end of the pipe so that we
# see EOF when parent closes its descriptor.
close $wfh;
# Wait for the parent process to finish its unshare() call by
# waiting for an EOF.
0 == sysread $rfh, my $c, 1 or error "read() did not receive EOF";
# The program's new[ug]idmap have to be used because they are
# setuid root. These privileges are needed to map the ids from
# /etc/sub[ug]id to the user namespace set up by the parent.
# Without these privileges, only the id of the user itself can be
# mapped into the new namespace.
#
# Since new[ug]idmap is setuid root we also don't need to write
# "deny" to /proc/$$/setgroups beforehand (this is otherwise
# required for unprivileged processes trying to write to
# /proc/$$/gid_map since kernel version 3.19 for security reasons)
# and therefore the parent process keeps its ability to change its
# own group here.
#
# Since /proc/$ppid/[ug]id_map can only be written to once,
# respectively, instead of making multiple calls to new[ug]idmap,
# we assemble a command line that makes one call each.
my $uidmapcmd = "";
my $gidmapcmd = "";
foreach (@{$idmap}) {
my ($t, $hostid, $nsid, $range) = @{$_};
if ($t ne "u" and $t ne "g" and $t ne "b") {
error "invalid idmap type: $t";
}
if ($t eq "u" or $t eq "b") {
$uidmapcmd .= " $hostid $nsid $range";
}
if ($t eq "g" or $t eq "b") {
$gidmapcmd .= " $hostid $nsid $range";
}
}
my $idmapcmd = '';
if ($uidmapcmd ne "") {
0 == system "newuidmap $ppid $uidmapcmd"
or error "newuidmap $ppid $uidmapcmd failed: $!";
}
if ($gidmapcmd ne "") {
0 == system "newgidmap $ppid $gidmapcmd"
or error "newgidmap $ppid $gidmapcmd failed: $!";
}
exit 0;
}
# parent
# After fork()-ing, the parent immediately calls unshare...
0 == syscall &SYS_unshare, $unshare_flags
or error "unshare() failed: $!";
# .. and then signals the child process that we are done with the
# unshare() call by sending an EOF.
close $wfh;
# Wait for the child process to finish its setup by waiting for its
# exit.
$cpid == waitpid $cpid, 0 or error "waitpid() failed: $!";
my $exit = $? >> 8;
if ($exit != 0) {
error "child had a non-zero exit status: $exit";
}
# Currently we are nobody (uid and gid are 65534). So we become root
# user and group instead.
#
# We are using direct syscalls instead of setting $(, $), $< and $>
# because then perl would do additional stuff which we don't need or
# want here, like checking /proc/sys/kernel/ngroups_max (which might
# not exist). It would also also call setgroups() in a way that makes
# the root user be part of the group unknown.
0 == syscall &SYS_setgid, 0 or error "setgid failed: $!";
0 == syscall &SYS_setuid, 0 or error "setuid failed: $!";
0 == syscall &SYS_setgroups, 0, 0 or error "setgroups failed: $!";
if (1) {
# When the pid namespace is also unshared, then processes expect a
# master pid to always be alive within the namespace. To achieve
# this, we fork() here instead of exec() to always have one dummy
# process running as pid 1 inside the namespace. This is also what
# the unshare tool does when used with the --fork option.
#
# Otherwise, without a pid 1, new processes cannot be forked
# anymore after pid 1 finished.
my $cpid = fork() // error "fork() failed: $!";
if ($cpid != 0) {
# The parent process will stay alive as pid 1 in this
# namespace until the child finishes executing. This is
# important because pid 1 must never die or otherwise nothing
# new can be forked.
$cpid == waitpid $cpid, 0 or error "waitpid() failed: $!";
exit($? >> 8);
}
}
&{$cmd}();
exit 0;
}
# parent
return $gcpid;
}
sub havemknod($) {
my $root = shift;
my $havemknod = 0;
if (-e "$root/test-dev-null") {
error "/test-dev-null already exists";
}
TEST: {
# we fork so that we can read STDERR
my $pid = open my $fh, '-|' // error "failed to fork(): $!";
if ($pid == 0) {
open(STDERR, '>&', STDOUT) or error "cannot open STDERR: $!";
# we use mknod(1) instead of the system call because creating the
# right dev_t argument requires makedev(3)
exec 'mknod', "$root/test-dev-null", 'c', '1', '3';
}
chomp(
my $content = do { local $/; <$fh> }
);
close $fh;
{
last TEST unless $? == 0 and $content eq '';
last TEST unless -c "$root/test-dev-null";
last TEST unless open my $fh, '>', "$root/test-dev-null";
last TEST unless print $fh 'test';
}
$havemknod = 1;
}
if (-e "$root/test-dev-null") {
unlink "$root/test-dev-null"
or error "cannot unlink /test-dev-null: $!";
}
return $havemknod;
}
sub print_progress {
if ($verbosity_level != 1) {
return;
}
my $perc = shift;
if (!-t STDERR) {
return;
}
if ($perc eq "done") {
# \e[2K clears everything on the current line (i.e. the progress bar)
print STDERR "\e[2Kdone\n";
return;
}
if ($perc >= 100) {
$perc = 100;
}
my $width = 50;
my $num_x = int($perc * $width / 100);
my $bar = '=' x $num_x;
if ($num_x != $width) {
$bar .= '>';
$bar .= ' ' x ($width - $num_x - 1);
}
printf STDERR "%6.2f [%s]\r", $perc, $bar;
}
sub run_progress {
my ($get_exec, $line_handler, $line_has_error, $chdir) = @_;
pipe my $rfh, my $wfh;
my $got_signal = 0;
my $ignore = sub {
info "run_progress() received signal $_[0]: waiting for child...";
};
# delay signals so that we can fork and change behaviour of the signal
# handler in parent and child without getting interrupted
my $sigset = POSIX::SigSet->new(SIGINT, SIGHUP, SIGPIPE, SIGTERM);
POSIX::sigprocmask(SIG_BLOCK, $sigset) or error "Can't block signals: $!";
my $pid1 = open(my $pipe, '-|') // error "failed to fork(): $!";
if ($pid1 == 0) {
# child: default signal handlers
$SIG{'INT'} = 'DEFAULT';
$SIG{'HUP'} = 'DEFAULT';
$SIG{'PIPE'} = 'DEFAULT';
$SIG{'TERM'} = 'DEFAULT';
# unblock all delayed signals (and possibly handle them)
POSIX::sigprocmask(SIG_UNBLOCK, $sigset)
or error "Can't unblock signals: $!";
close $rfh;
# Unset the close-on-exec flag, so that the file descriptor does not
# get closed when we exec
my $flags = fcntl($wfh, F_GETFD, 0) or error "fcntl F_GETFD: $!";
fcntl($wfh, F_SETFD, $flags & ~FD_CLOEXEC)
or error "fcntl F_SETFD: $!";
my $fd = fileno $wfh;
# redirect stderr to stdout so that we can capture it
open(STDERR, '>&', STDOUT) or error "cannot open STDOUT: $!";
my @execargs = $get_exec->($fd);
# before apt 1.5, "apt-get update" attempted to chdir() into the
# working directory. This will fail if the current working directory
# is not accessible by the user (for example in unshare mode). See
# Debian bug #860738
if (defined $chdir) {
chdir $chdir or error "failed chdir() to $chdir: $!";
}
eval 'Devel::Cover::set_coverage("none")' if $is_covering;
exec { $execargs[0] } @execargs
or error 'cannot exec() ' . (join ' ', @execargs);
}
close $wfh;
# spawn two processes:
# parent will parse stdout to look for errors
# child will parse $rfh for the progress meter
my $pid2 = fork() // error "failed to fork(): $!";
if ($pid2 == 0) {
# child: default signal handlers
$SIG{'INT'} = 'IGNORE';
$SIG{'HUP'} = 'IGNORE';
$SIG{'PIPE'} = 'IGNORE';
$SIG{'TERM'} = 'IGNORE';
# unblock all delayed signals (and possibly handle them)
POSIX::sigprocmask(SIG_UNBLOCK, $sigset)
or error "Can't unblock signals: $!";
print_progress 0.0;
while (my $line = <$rfh>) {
my $output = $line_handler->($line);
next unless $output;
print_progress $output;
}
print_progress "done";
exit 0;
}
# parent: ignore signals
# by using "local", the original is automatically restored once the
# function returns
local $SIG{'INT'} = $ignore;
local $SIG{'HUP'} = $ignore;
local $SIG{'PIPE'} = $ignore;
local $SIG{'TERM'} = $ignore;
# unblock all delayed signals (and possibly handle them)
POSIX::sigprocmask(SIG_UNBLOCK, $sigset)
or error "Can't unblock signals: $!";
my $output = '';
my $has_error = 0;
while (my $line = <$pipe>) {
$has_error = $line_has_error->($line);
if ($verbosity_level >= 2) {
print STDERR $line;
} else {
# forward captured apt output
$output .= $line;
}
}
close($pipe);
my $fail = 0;
if ($? != 0 or $has_error) {
$fail = 1;
}
waitpid $pid2, 0;
$? == 0 or error "progress parsing failed";
if ($got_signal) {
error "run_progress() received signal: $got_signal";
}
# only print failure after progress output finished or otherwise it
# might interfere with the remaining output
if ($fail) {
if ($verbosity_level >= 1) {
print STDERR $output;
}
error((join ' ', $get_exec->('<$fd>')) . ' failed');
}
}
sub run_dpkg_progress {
my $options = shift;
my @debs = @{ $options->{PKGS} // [] };
my $get_exec
= sub { return @{ $options->{ARGV} }, "--status-fd=$_[0]", @debs; };
my $line_has_error = sub { return 0; };
my $num = 0;
# each package has one install and one configure step, thus the total
# number is twice the number of packages
my $total = (scalar @debs) * 2;
my $line_handler = sub {
if ($_[0] =~ /^processing: (install|configure): /) {
$num += 1;
}
return $num / $total * 100;
};
run_progress $get_exec, $line_handler, $line_has_error;
}
sub run_apt_progress {
my $options = shift;
my @debs = @{ $options->{PKGS} // [] };
my $get_exec = sub {
return (
@{ $options->{ARGV} },
"-oAPT::Status-Fd=$_[0]",
# prevent apt from messing up the terminal and allow dpkg to
# receive SIGINT and quit immediately without waiting for
# maintainer script to finish
'-oDpkg::Use-Pty=false',
@debs
);
};
my $line_has_error = sub { return 0; };
if ($options->{FIND_APT_WARNINGS}) {
$line_has_error = sub {
# apt-get doesn't report a non-zero exit if the update failed.
# Thus, we have to parse its output. See #778357, #776152, #696335
# and #745735
if ($_[0] =~ /^(W: |Err:)/) {
return 1;
}
return 0;
};
}
my $line_handler = sub {
if ($_[0] =~ /(pmstatus|dlstatus):[^:]+:(\d+\.\d+):.*/) {
return $2;
}
};
run_progress $get_exec, $line_handler, $line_has_error, $options->{CHDIR};
}
sub run_chroot(&$) {
my $cmd = shift;
my $options = shift;
my @cleanup_tasks = ();
my $cleanup = sub {
my $signal = $_[0];
while (my $task = pop @cleanup_tasks) {
$task->();
}
if ($signal) {
warning "pid $PID cought signal: $signal";
exit 1;
}
};
local $SIG{INT} = $cleanup;
local $SIG{HUP} = $cleanup;
local $SIG{PIPE} = $cleanup;
local $SIG{TERM} = $cleanup;
eval {
if (any { $_ eq $options->{mode} } ('root', 'unshare')) {
# if more than essential should be installed, make the system look
# more like a real one by creating or bind-mounting the device
# nodes
foreach my $file (@devfiles) {
my ($fname, $mode, $type, $linkname, $devmajor, $devminor)
= @{$file};
next if $fname eq './dev/';
if ($type == 0) { # normal file
error "type 0 not implemented";
} elsif ($type == 1) { # hardlink
error "type 1 not implemented";
} elsif ($type == 2) { # symlink
if (!$options->{havemknod}) {
if ( $options->{mode} eq 'fakechroot'
and $linkname =~ /^\/proc/) {
# there is no /proc in fakechroot mode
next;
}
if (
any { $_ eq $options->{mode} }
('root', 'unshare')
) {
push @cleanup_tasks, sub {
unlink "$options->{root}/$fname"
or warn "cannot unlink $fname: $!";
}
}
symlink $linkname, "$options->{root}/$fname"
or error "cannot create symlink $fname";
}
} elsif ($type == 3 or $type == 4) {
# character/block special
if (!$options->{havemknod}) {
open my $fh, '>', "$options->{root}/$fname"
or error "cannot open $options->{root}/$fname: $!";
close $fh;
if ($options->{mode} eq 'unshare') {
push @cleanup_tasks, sub {
0 == system('umount', '--no-mtab',
"$options->{root}/$fname")
or warn "umount $fname failed: $?";
unlink "$options->{root}/$fname"
or warn "cannot unlink $fname: $!";
};
} elsif ($options->{mode} eq 'root') {
push @cleanup_tasks, sub {
0 == system('umount',
"$options->{root}/$fname")
or warn "umount failed: $?";
unlink "$options->{root}/$fname"
or warn "cannot unlink $fname: $!";
};
} else {
error "unknown mode: $options->{mode}";
}
0 == system('mount', '-o', 'bind', "/$fname",
"$options->{root}/$fname")
or error "mount $fname failed: $?";
}
} elsif ($type == 5) { # directory
if (!$options->{havemknod}) {
if (
any { $_ eq $options->{mode} }
('root', 'unshare')
) {
push @cleanup_tasks, sub {
rmdir "$options->{root}/$fname"
or warn "cannot rmdir $fname: $!";
}
}
if (-e "$options->{root}/$fname") {
if (!-d "$options->{root}/$fname") {
error "$fname already exists but is not a"
. " directory";
}
} else {
my $num_created
= make_path "$options->{root}/$fname",
{ error => \my $err };
if ($err && @$err) {
error(
join "; ",
(
map {
"cannot create "
. (join ": ", %{$_})
} @$err
));
} elsif ($num_created == 0) {
error "cannot create $options->{root}/$fname";
}
}
chmod $mode, "$options->{root}/$fname"
or error "cannot chmod $fname: $!";
}
if ($options->{mode} eq 'unshare') {
push @cleanup_tasks, sub {
0 == system('umount', '--no-mtab',
"$options->{root}/$fname")
or warn "umount $fname failed: $?";
};
} elsif ($options->{mode} eq 'root') {
push @cleanup_tasks, sub {
0 == system('umount', "$options->{root}/$fname")
or warn "umount $fname failed: $?";
};
} else {
error "unknown mode: $options->{mode}";
}
0 == system('mount', '-o', 'bind', "/$fname",
"$options->{root}/$fname")
or error "mount $fname failed: $?";
} else {
error "unsupported type: $type";
}
}
} elsif (
any { $_ eq $options->{mode} }
('proot', 'fakechroot', 'chrootless')
) {
# we cannot mount in fakechroot and proot mode
# in proot mode we have /dev bind-mounted already through
# --bind=/dev
} else {
error "unknown mode: $options->{mode}";
}
# We can only mount /proc and /sys after extracting the essential
# set because if we mount it before, then base-files will not be able
# to extract those
if ($options->{mode} eq 'root') {
push @cleanup_tasks, sub {
0 == system('umount', "$options->{root}/sys")
or warn "umount /sys failed: $?";
};
0 == system(
'mount', '-t', 'sysfs', '-o',
'nosuid,nodev,noexec', 'sys', "$options->{root}/sys"
) or error "mount /sys failed: $?";
} elsif ($options->{mode} eq 'unshare') {
# naturally we have to clean up after ourselves in sudo mode where
# we do a real mount. But we also need to unmount in unshare mode
# because otherwise, even with the --one-file-system tar option,
# the permissions of the mount source will be stored and not the
# mount target (the directory)
push @cleanup_tasks, sub {
# since we cannot write to /etc/mtab we need --no-mtab
# unmounting /sys only seems to be successful with --lazy
0 == system('umount', '--no-mtab', '--lazy',
"$options->{root}/sys")
or warn "umount /sys failed: $?";
};
# without the network namespace unshared, we cannot mount a new
# sysfs. Since we need network, we just bind-mount.
#
# we have to rbind because just using bind results in "wrong fs
# type, bad option, bad superblock" error
0 == system('mount', '-o', 'rbind', '/sys', "$options->{root}/sys")
or error "mount /sys failed: $?";
} elsif (
any { $_ eq $options->{mode} }
('proot', 'fakechroot', 'chrootless')
) {
# we cannot mount in fakechroot and proot mode
# in proot mode we have /proc bind-mounted already through
# --bind=/proc
} else {
error "unknown mode: $options->{mode}";
}
if ($options->{mode} eq 'root') {
push @cleanup_tasks, sub {
# some maintainer scripts mount additional stuff into /proc
# which we need to unmount beforehand
if (is_mountpoint("$options->{root}/proc/sys/fs/binfmt_misc"))
{
0 == system('umount',
"$options->{root}/proc/sys/fs/binfmt_misc")
or error "umount /proc/sys/fs/binfmt_misc failed: $?";
}
0 == system('umount', "$options->{root}/proc")
or error "umount /proc failed: $?";
};
0 == system('mount', '-t', 'proc', 'proc', "$options->{root}/proc")
or error "mount /proc failed: $?";
} elsif ($options->{mode} eq 'unshare') {
# naturally we have to clean up after ourselves in sudo mode where
# we do a real mount. But we also need to unmount in unshare mode
# because otherwise, even with the --one-file-system tar option,
# the permissions of the mount source will be stored and not the
# mount target (the directory)
push @cleanup_tasks, sub {
# since we cannot write to /etc/mtab we need --no-mtab
0 == system('umount', '--no-mtab', "$options->{root}/proc")
or error "umount /proc failed: $?";
};
0 == system('mount', '-t', 'proc', 'proc', "$options->{root}/proc")
or error "mount /proc failed: $?";
} elsif (
any { $_ eq $options->{mode} }
('proot', 'fakechroot', 'chrootless')
) {
# we cannot mount in fakechroot and proot mode
# in proot mode we have /sys bind-mounted already through
# --bind=/sys
} else {
error "unknown mode: $options->{mode}";
}
# prevent daemons from starting
# the directory might not exist in custom variant, for example
if (-d "$options->{root}/usr/sbin/") {
open my $fh, '>', "$options->{root}/usr/sbin/policy-rc.d"
or error "cannot open policy-rc.d: $!";
print $fh "#!/bin/sh\n";
print $fh "exit 101\n";
close $fh;
chmod 0755, "$options->{root}/usr/sbin/policy-rc.d"
or error "cannot chmod policy-rc.d: $!";
}
# the file might not exist if it was removed in a hook
if (-e "$options->{root}/sbin/start-stop-daemon") {
if (-e "$options->{root}/sbin/start-stop-daemon.REAL") {
error "$options->{root}/sbin/start-stop-daemon.REAL already"
. " exists";
}
move(
"$options->{root}/sbin/start-stop-daemon",
"$options->{root}/sbin/start-stop-daemon.REAL"
) or error "cannot move start-stop-daemon: $!";
open my $fh, '>', "$options->{root}/sbin/start-stop-daemon"
or error "cannot open start-stop-daemon: $!";
print $fh "#!/bin/sh\n";
print $fh "echo \"Warning: Fake start-stop-daemon called, doing"
. " nothing\">&2\n";
close $fh;
chmod 0755, "$options->{root}/sbin/start-stop-daemon"
or error "cannot chmod start-stop-daemon: $!";
}
&{$cmd}();
# cleanup
if (-e "$options->{root}/sbin/start-stop-daemon.REAL") {
move(
"$options->{root}/sbin/start-stop-daemon.REAL",
"$options->{root}/sbin/start-stop-daemon"
) or error "cannot move start-stop-daemon: $!";
}
if (-e "$options->{root}/usr/sbin/policy-rc.d") {
unlink "$options->{root}/usr/sbin/policy-rc.d"
or error "cannot unlink policy-rc.d: $!";
}
};
my $error = $@;
# we use the cleanup function to do the unmounting
$cleanup->(0);
if ($error) {
error "run_chroot failed: $error";
}
}
sub run_hooks($$) {
my $name = shift;
my $options = shift;
if (scalar @{ $options->{"${name}_hook"} } == 0) {
return;
}
my $runner = sub {
foreach my $script (@{ $options->{"${name}_hook"} }) {
if ($script
=~ /^(copy-in|copy-out|tar-in|tar-out|upload|download) /) {
info "running special hook: $script";
if (
any { $_ eq $options->{variant} } ('extract', 'custom')
and any { $_ eq $options->{mode} }
('fakechroot', 'proot') and $name ne 'setup'
) {
info "the copy-in, copy-out, tar-in and tar-out commands"
. " in fakechroot mode or proot mode might fail in"
. " extract and custom variants because there might be"
. " no tar inside the chroot";
}
my $pid = fork() // error "fork() failed: $!";
if ($pid == 0) {
# whatever the script writes on stdout is sent to the
# socket
# whatever is written to the socket, send to stdin
open(STDOUT, '>&', $options->{hooksock})
or error "cannot open STDOUT: $!";
open(STDIN, '<&', $options->{hooksock})
or error "cannot open STDIN: $!";
# we execute ourselves under sh to avoid having to
# implement a clever parser of the quoting used in $script
# for the filenames
my $prefix = "";
if ($is_covering) {
$prefix
= "$EXECUTABLE_NAME -MDevel::Cover=-silent,-nogcov ";
}
exec 'sh', '-c',
"$prefix$PROGRAM_NAME --hook-helper"
. " \"\$1\" \"\$2\" \"\$3\" \"\$4\" \"\$5\" $script",
'exec', $options->{root}, $options->{mode}, $name,
(
defined $options->{qemu}
? "qemu-$options->{qemu}"
: 'env',
$verbosity_level
);
}
waitpid($pid, 0);
$? == 0 or error "special hook failed with exit code $?";
} elsif (-x $script || $script !~ m/[^\w@\%+=:,.\/-]/a) {
info "running --$name-hook directly: $script $options->{root}";
# execute it directly if it's an executable file
# or if it there are no shell metacharacters
# (the /a regex modifier makes \w match only ASCII)
0 == system($script, $options->{root})
or error "command failed: $script";
} else {
info "running --$name-hook in shell: sh -c '$script' exec"
. " $options->{root}";
# otherwise, wrap everything in sh -c
0 == system('sh', '-c', $script, 'exec', $options->{root})
or error "command failed: $script";
}
}
};
if ($name eq 'setup') {
# execute directly without mounting anything (the mount points do not
# exist yet)
&{$runner}();
} else {
run_chroot \&$runner, $options;
}
}
sub setup {
my $options = shift;
foreach my $key (sort keys %{$options}) {
my $value = $options->{$key};
if (!defined $value) {
next;
}
if (ref $value eq '') {
debug "$key: $options->{$key}";
} elsif (ref $value eq 'ARRAY') {
debug "$key: [" . (join ', ', @{$value}) . "]";
} elsif (ref $value eq 'GLOB') {
debug "$key: GLOB";
} else {
error "unknown type for key $key: " . (ref $value);
}
}
my ($conf, $tmpfile) = tempfile(UNLINK => 1)
or error "cannot open apt.conf: $!";
print $conf "Apt::Architecture \"$options->{nativearch}\";\n";
# the host system might have configured additional architectures
# force only the native architecture
if (scalar @{ $options->{foreignarchs} } > 0) {
print $conf "Apt::Architectures { \"$options->{nativearch}\"; ";
foreach my $arch (@{ $options->{foreignarchs} }) {
print $conf "\"$arch\"; ";
}
print $conf "};\n";
} else {
print $conf "Apt::Architectures \"$options->{nativearch}\";\n";
}
print $conf "Dir \"$options->{root}\";\n";
# not needed anymore for apt 1.3 and newer
print $conf
"Dir::State::Status \"$options->{root}/var/lib/dpkg/status\";\n";
# for authentication, use the keyrings from the host
print $conf "Dir::Etc::Trusted \"$options->{apttrusted}\";\n";
print $conf "Dir::Etc::TrustedParts \"$options->{apttrustedparts}\";\n";
if ($options->{variant} ne 'apt') {
# apt considers itself essential. Thus, when generating an EDSP
# document for an external solver, it will add the Essential:yes field
# to the apt package stanza. This is unnecessary for any other variant
# than 'apt' because in all other variants we compile the set of
# packages we consider essential ourselves and for the 'essential'
# variant it would even be wrong to add apt. This workaround is only
# needed when apt is used with an external solver but doesn't hurt
# otherwise and we don't have a good way to figure out whether apt is
# using an external solver or not short of parsing the --aptopt
# options.
print $conf "pkgCacheGen::ForceEssential \",\";\n";
}
close $conf;
{
my @directories = (
'/etc/apt/apt.conf.d', '/etc/apt/sources.list.d',
'/etc/apt/preferences.d', '/var/cache/apt',
'/var/lib/apt/lists/partial', '/var/lib/dpkg',
'/etc/dpkg/dpkg.cfg.d/'
);
# if dpkg and apt operate from the outside we need some more
# directories because dpkg and apt might not even be installed inside
# the chroot
if ($options->{mode} eq 'chrootless') {
push @directories,
(
'/var/log/apt', '/var/lib/dpkg/triggers',
'/var/lib/dpkg/info', '/var/lib/dpkg/alternatives',
'/var/lib/dpkg/updates'
);
}
foreach my $dir (@directories) {
if (-e "$options->{root}/$dir") {
if (!-d "$options->{root}/$dir") {
error "$dir already exists but is not a directory";
}
} else {
my $num_created = make_path "$options->{root}/$dir",
{ error => \my $err };
if ($err && @$err) {
error(
join "; ",
(map { "cannot create " . (join ": ", %{$_}) } @$err));
} elsif ($num_created == 0) {
error "cannot create $options->{root}/$dir";
}
}
}
}
# We put certain configuration items in their own configuration file
# because they have to be valid for apt invocation from outside as well as
# from inside the chroot.
# The config filename is chosen such that any settings in it will be
# overridden by what the user specified with --aptopt.
{
open my $fh, '>', "$options->{root}/etc/apt/apt.conf.d/00mmdebstrap"
or error "cannot open /etc/apt/apt.conf.d/00mmdebstrap: $!";
print $fh "Apt::Install-Recommends false;\n";
print $fh "Acquire::Languages \"none\";\n";
close $fh;
}
{
open my $fh, '>', "$options->{root}/var/lib/dpkg/status"
or error "failed to open(): $!";
close $fh;
}
# /var/lib/dpkg/available is required to exist or otherwise package
# removals will fail
{
open my $fh, '>', "$options->{root}/var/lib/dpkg/available"
or error "failed to open(): $!";
close $fh;
}
# /var/lib/dpkg/cmethopt is used by dselect
# see #930788
{
open my $fh, '>', "$options->{root}/var/lib/dpkg/cmethopt"
or error "failed to open(): $!";
print $fh "apt apt\n";
close $fh;
}
# we create /var/lib/dpkg/arch inside the chroot either if there is more
# than the native architecture in the chroot or if chrootless mode is
# used to create a chroot of a different architecture than the native
# architecture outside the chroot.
chomp(my $hostarch = `dpkg --print-architecture`);
if (
scalar @{ $options->{foreignarchs} } > 0
or ( $options->{mode} eq 'chrootless'
and $hostarch ne $options->{nativearch})
) {
open my $fh, '>', "$options->{root}/var/lib/dpkg/arch"
or error "cannot open /var/lib/dpkg/arch: $!";
print $fh "$options->{nativearch}\n";
foreach my $arch (@{ $options->{foreignarchs} }) {
print $fh "$arch\n";
}
close $fh;
}
if (scalar @{ $options->{aptopts} } > 0) {
open my $fh, '>', "$options->{root}/etc/apt/apt.conf.d/99mmdebstrap"
or error "cannot open /etc/apt/apt.conf.d/99mmdebstrap: $!";
foreach my $opt (@{ $options->{aptopts} }) {
if (-r $opt) {
# flush handle because copy() uses syswrite() which bypasses
# buffered IO
$fh->flush();
copy $opt, $fh or error "cannot copy $opt: $!";
} else {
print $fh $opt;
if ($opt !~ /;$/) {
print $fh ';';
}
if ($opt !~ /\n$/) {
print $fh "\n";
}
}
}
close $fh;
}
if (scalar @{ $options->{dpkgopts} } > 0) {
# FIXME: in chrootless mode, dpkg will only read the configuration
# from the host
open my $fh, '>', "$options->{root}/etc/dpkg/dpkg.cfg.d/99mmdebstrap"
or error "cannot open /etc/dpkg/dpkg.cfg.d/99mmdebstrap: $!";
foreach my $opt (@{ $options->{dpkgopts} }) {
if (-r $opt) {
# flush handle because copy() uses syswrite() which bypasses
# buffered IO
$fh->flush();
copy $opt, $fh or error "cannot copy $opt: $!";
} else {
print $fh $opt;
if ($opt !~ /\n$/) {
print $fh "\n";
}
}
}
close $fh;
}
## setup merged usr
#my @amd64_dirs = ('lib32', 'lib64', 'libx32'); # only amd64 for now
#foreach my $dir ("bin", "sbin", "lib", @amd64_dirs) {
# symlink "usr/$dir", "$options->{root}/$dir"
# or die "cannot create symlink: $!";
# make_path("$options->{root}/usr/$dir")
# or die "cannot create /usr/$dir: $!";
#}
{
open my $fh, '>', "$options->{root}/etc/fstab"
or error "cannot open fstab: $!";
print $fh "# UNCONFIGURED FSTAB FOR BASE SYSTEM\n";
close $fh;
chmod 0644, "$options->{root}/etc/fstab"
or error "cannot chmod fstab: $!";
}
# write /etc/apt/sources.list
{
open my $fh, '>', "$options->{root}/etc/apt/sources.list"
or error "cannot open /etc/apt/sources.list: $!";
print $fh $options->{sourceslist};
close $fh;
}
# allow network access from within
if (-e "/etc/resolv.conf") {
copy("/etc/resolv.conf", "$options->{root}/etc/resolv.conf")
or error "cannot copy /etc/resolv.conf: $!";
} else {
warning("Host system does not have a /etc/resolv.conf to copy into the"
. " rootfs.");
}
if (-e "/etc/hostname") {
copy("/etc/hostname", "$options->{root}/etc/hostname")
or error "cannot copy /etc/hostname: $!";
} else {
warning("Host system does not have a /etc/hostname to copy into the"
. " rootfs.");
}
if ($options->{havemknod}) {
foreach my $file (@devfiles) {
my ($fname, $mode, $type, $linkname, $devmajor, $devminor)
= @{$file};
if ($type == 0) { # normal file
error "type 0 not implemented";
} elsif ($type == 1) { # hardlink
error "type 1 not implemented";
} elsif ($type == 2) { # symlink
if ( $options->{mode} eq 'fakechroot'
and $linkname =~ /^\/proc/) {
# there is no /proc in fakechroot mode
next;
}
symlink $linkname, "$options->{root}/$fname"
or error "cannot create symlink $fname";
next; # chmod cannot work on symlinks
} elsif ($type == 3) { # character special
0 == system('mknod', "$options->{root}/$fname", 'c',
$devmajor, $devminor)
or error "mknod failed: $?";
} elsif ($type == 4) { # block special
0 == system('mknod', "$options->{root}/$fname", 'b',
$devmajor, $devminor)
or error "mknod failed: $?";
} elsif ($type == 5) { # directory
if (-e "$options->{root}/$fname") {
if (!-d "$options->{root}/$fname") {
error "$fname already exists but is not a directory";
}
} else {
my $num_created = make_path "$options->{root}/$fname",
{ error => \my $err };
if ($err && @$err) {
error(
join "; ",
(
map { "cannot create " . (join ": ", %{$_}) }
@$err
));
} elsif ($num_created == 0) {
error "cannot create $options->{root}/$fname";
}
}
} else {
error "unsupported type: $type";
}
chmod $mode, "$options->{root}/$fname"
or error "cannot chmod $fname: $!";
}
}
# we tell apt about the configuration via a config file passed via the
# APT_CONFIG environment variable instead of using the --option command
# line arguments because configuration settings like Dir::Etc have already
# been evaluated at the time that apt takes its command line arguments
# into account.
$ENV{"APT_CONFIG"} = "$tmpfile";
# when apt-get update is run by the root user, then apt will attempt to
# drop privileges to the _apt user. This will fail if the _apt user does
# not have permissions to read the root directory. In that case, we have
# to disable apt sandboxing.
if ($options->{mode} eq 'root') {
my $partial = '/var/lib/apt/lists/partial';
if (
system('/usr/lib/apt/apt-helper', 'drop-privs', '--', 'test',
'-r', "$options->{root}$partial") != 0
) {
warning "Download is performed unsandboxed as root as file"
. " $options->{root}$partial couldn't be accessed by user _apt";
open my $fh, '>>', $tmpfile
or error "cannot open $tmpfile for appending: $!";
print $fh "APT::Sandbox::User \"root\";\n";
close $fh;
}
}
# setting PATH for chroot, ldconfig, start-stop-daemon...
if (defined $ENV{PATH} && $ENV{PATH} ne "") {
$ENV{PATH} = "$ENV{PATH}:/usr/sbin:/usr/bin:/sbin:/bin";
} else {
$ENV{PATH} = "/usr/sbin:/usr/bin:/sbin:/bin";
}
# run setup hooks
run_hooks('setup', $options);
info "running apt-get update...";
run_apt_progress({
ARGV => ['apt-get', 'update'],
CHDIR => $options->{root},
FIND_APT_WARNINGS => 1
});
# check if anything was downloaded at all
{
open my $fh, '-|', 'apt-get',
'indextargets' // error "failed to fork(): $!";
chomp(
my $indextargets = do { local $/; <$fh> }
);
close $fh;
if ($indextargets eq '') {
info "content of /etc/apt/sources.list:";
if ($verbosity_level >= 1) {
copy("$options->{root}/etc/apt/sources.list", *STDERR);
}
error "apt-get update didn't download anything";
}
}
my @pkgs_to_install;
for my $incl (@{ $options->{include} }) {
for my $pkg (split /[,\s]+/, $incl) {
# strip leading and trailing whitespace
$pkg =~ s/^\s+|\s+$//g;
# skip if the remainder is an empty string
if ($pkg eq '') {
next;
}
# do not append component if it's already in the list
if (any { $_ eq $pkg } @pkgs_to_install) {
next;
}
push @pkgs_to_install, $pkg;
}
}
if ($options->{variant} eq 'buildd') {
push @pkgs_to_install, 'build-essential';
}
# To figure out the right package set for the apt variant we can use:
# $ apt-get dist-upgrade -o dir::state::status=/dev/null
# This is because that variants only contain essential packages and
# apt and libapt treats apt as essential. If we want to install less
# (essential variant) then we have to compute the package set ourselves.
# Same if we want to install priority based variants.
if (any { $_ eq $options->{variant} } ('extract', 'custom')) {
info "downloading packages with apt...";
run_apt_progress({
ARGV => [
'apt-get', '--yes',
'-oApt::Get::Download-Only=true', 'install'
],
PKGS => [@pkgs_to_install],
});
} elsif ($options->{variant} eq 'apt') {
# if we just want to install Essential:yes packages, apt and their
# dependencies then we can make use of libapt treating apt as
# implicitly essential. An upgrade with the (currently) empty status
# file will trigger an installation of the essential packages plus apt.
#
# 2018-09-02, #debian-dpkg on OFTC, times in UTC+2
# 23:39 < josch> I'll just put it in my script and if it starts
# breaking some time I just say it's apt's fault. :P
# 23:42 < DonKult> that is how it usually works, so yes, do that :P (<-
# and please add that line next to it so you can
# remind me in 5+ years that I said that after I wrote
# in the bugreport: "Are you crazy?!? Nobody in his
# right mind would even suggest depending on it!")
info "downloading packages with apt...";
run_apt_progress({
ARGV => [
'apt-get', '--yes',
'-oApt::Get::Download-Only=true', 'dist-upgrade'
],
});
} elsif (
any { $_ eq $options->{variant} } (
'essential', 'standard', 'important', 'required', 'buildd',
'minbase'
)
) {
my %ess_pkgs;
open(my $pipe_apt, '-|', 'apt-get', 'indextargets', '--format',
'$(FILENAME)', 'Created-By: Packages')
or error "cannot start apt-get indextargets: $!";
while (my $fname = <$pipe_apt>) {
chomp $fname;
open(my $pipe_cat, '-|', '/usr/lib/apt/apt-helper', 'cat-file',
$fname)
or error "cannot start apt-helper cat-file: $!";
my $pkgname;
my $ess = '';
my $prio = 'optional';
my $arch = '';
while (my $line = <$pipe_cat>) {
chomp $line;
# Dpkg::Index takes 10 seconds to parse a typical Packages
# file. Thus we instead use a simple parser that just retrieve
# the information we need.
if ($line ne "") {
if ($line =~ /^Package: (.*)/) {
$pkgname = $1;
} elsif ($line =~ /^Essential: yes$/) {
$ess = 'yes';
} elsif ($line =~ /^Priority: (.*)/) {
$prio = $1;
} elsif ($line =~ /^Architecture: (.*)/) {
$arch = $1;
}
next;
}
# we are only interested of packages of native architecture or
# Architecture:all
if ($arch eq $options->{nativearch} or $arch eq 'all') {
# the line is empty, thus a package stanza just finished
# processing and we can handle it now
if ($ess eq 'yes') {
$ess_pkgs{$pkgname} = ();
} elsif ($options->{variant} eq 'essential') {
# for this variant we are only interested in the
# essential packages
} elsif (
any { $_ eq $options->{variant} } (
'standard', 'important', 'required', 'buildd',
'minbase'
)
) {
if ($prio eq 'optional' or $prio eq 'extra') {
# always ignore packages of priority optional and
# extra
} elsif ($prio eq 'standard') {
if (
none { $_ eq $options->{variant} }
('important', 'required', 'buildd', 'minbase')
) {
push @pkgs_to_install, $pkgname;
}
} elsif ($prio eq 'important') {
if (
none { $_ eq $options->{variant} }
('required', 'buildd', 'minbase')
) {
push @pkgs_to_install, $pkgname;
}
} elsif ($prio eq 'required') {
# required packages are part of all sets except
# essential and apt
push @pkgs_to_install, $pkgname;
} else {
error "unknown priority: $prio";
}
} else {
error "unknown variant: $options->{variant}";
}
}
# reset values
undef $pkgname;
$ess = '';
$prio = 'optional';
$arch = '';
}
close $pipe_cat;
$? == 0 or error "apt-helper cat-file failed: $?";
}
close $pipe_apt;
$? == 0 or error "apt-get indextargets failed: $?";
debug "Identified the following Essential:yes packages:";
foreach my $pkg (sort keys %ess_pkgs) {
debug " $pkg";
}
info "downloading packages with apt...";
run_apt_progress({
ARGV => [
'apt-get', '--yes',
'-oApt::Get::Download-Only=true', 'install'
],
PKGS => [keys %ess_pkgs],
});
} else {
error "unknown variant: $options->{variant}";
}
# extract the downloaded packages
my @essential_pkgs;
{
my $apt_archives = "/var/cache/apt/archives/";
opendir my $dh, "$options->{root}/$apt_archives"
or error "cannot read $apt_archives";
while (my $deb = readdir $dh) {
if ($deb !~ /\.deb$/) {
next;
}
$deb = "$apt_archives/$deb";
if (!-f "$options->{root}/$deb") {
next;
}
push @essential_pkgs, $deb;
}
close $dh;
}
if (scalar @essential_pkgs == 0) {
# check if a file:// URI was used
open(my $pipe_apt, '-|', 'apt-get', 'indextargets', '--format',
'$(URI)', 'Created-By: Packages')
or error "cannot start apt-get indextargets: $!";
while (my $uri = <$pipe_apt>) {
if ($uri =~ /^file:\/\//) {
error
"nothing got downloaded -- use copy:// instead of file://";
}
}
error "nothing got downloaded";
}
# We have to extract the packages from @essential_pkgs either if we run in
# chrootless mode and extract variant or in any other mode.
# In other words, the only scenario in which the @essential_pkgs are not
# extracted are in chrootless mode in any other than the extract variant.
if ($options->{mode} eq 'chrootless' and $options->{variant} ne 'extract')
{
# nothing to do
} else {
info "extracting archives...";
print_progress 0.0;
my $counter = 0;
my $total = scalar @essential_pkgs;
foreach my $deb (@essential_pkgs) {
$counter += 1;
# not using dpkg-deb --extract as that would replace the
# merged-usr symlinks with plain directories
pipe my $rfh, my $wfh;
my $pid1 = fork() // error "fork() failed: $!";
if ($pid1 == 0) {
open(STDOUT, '>&', $wfh) or error "cannot open STDOUT: $!";
debug("running dpkg-deb --fsys-tarfile $options->{root}/$deb");
eval 'Devel::Cover::set_coverage("none")' if $is_covering;
exec 'dpkg-deb', '--fsys-tarfile', "$options->{root}/$deb";
}
my $pid2 = fork() // error "fork() failed: $!";
if ($pid2 == 0) {
open(STDIN, '<&', $rfh) or error "cannot open STDIN: $!";
debug( "running tar -C $options->{root}"
. " --keep-directory-symlink --extract --file -");
eval 'Devel::Cover::set_coverage("none")' if $is_covering;
exec 'tar', '-C', $options->{root},
'--keep-directory-symlink', '--extract', '--file', '-';
}
waitpid($pid1, 0);
$? == 0 or error "dpkg-deb --fsys-tarfile failed: $?";
waitpid($pid2, 0);
$? == 0 or error "tar --extract failed: $?";
print_progress($counter / $total * 100);
}
print_progress "done";
}
if ($options->{mode} eq 'chrootless') {
info "installing packages...";
# FIXME: the dpkg config from the host is parsed before the command
# line arguments are parsed and might break this mode
# Example: if the host has --path-exclude set, then this will also
# affect the chroot.
my @chrootless_opts = (
'-oDPkg::Options::=--force-not-root',
'-oDPkg::Options::=--force-script-chrootless',
'-oDPkg::Options::=--root=' . $options->{root},
'-oDPkg::Options::=--log=' . "$options->{root}/var/log/dpkg.log"
);
if (defined $options->{qemu}) {
# The binfmt support on the outside is used, so qemu needs to know
# where it has to look for shared libraries
if (defined $ENV{QEMU_LD_PREFIX}
&& $ENV{QEMU_LD_PREFIX} ne "") {
$ENV{QEMU_LD_PREFIX} = "$ENV{QEMU_LD_PREFIX}:$options->{root}";
} else {
$ENV{QEMU_LD_PREFIX} = $options->{root};
}
}
if ($options->{variant} eq 'extract') {
# nothing to do
} else {
run_apt_progress({
ARGV => ['apt-get', '--yes', @chrootless_opts, 'install'],
PKGS => [map { "$options->{root}/$_" } @essential_pkgs],
});
}
if (any { $_ eq $options->{variant} } ('extract', 'custom')) {
# nothing to do
} elsif (
any { $_ eq $options->{variant} } (
'essential', 'apt', 'standard', 'important',
'required', 'buildd', 'minbase'
)
) {
# run essential hooks
run_hooks('essential', $options);
if (scalar @pkgs_to_install > 0) {
run_apt_progress({
ARGV =>
['apt-get', '--yes', @chrootless_opts, 'install'],
PKGS => [@pkgs_to_install],
});
}
} else {
error "unknown variant: $options->{variant}";
}
} elsif (
any { $_ eq $options->{mode} }
('root', 'unshare', 'fakechroot', 'proot')
) {
if (any { $_ eq $options->{variant} } ('extract')) {
# nothing to do
} elsif (
any { $_ eq $options->{variant} } (
'custom', 'essential', 'apt', 'standard',
'important', 'required', 'buildd', 'minbase'
)
) {
if ($options->{mode} eq 'fakechroot') {
# this borrows from and extends
# /etc/fakechroot/debootstrap.env and
# /etc/fakechroot/chroot.env
{
my @fakechrootsubst = ();
foreach my $dir ('/usr/sbin', '/usr/bin', '/sbin', '/bin')
{
push @fakechrootsubst,
"$dir/chroot=/usr/sbin/chroot.fakechroot";
push @fakechrootsubst, "$dir/mkfifo=/bin/true";
push @fakechrootsubst, "$dir/ldconfig=/bin/true";
push @fakechrootsubst,
"$dir/ldd=/usr/bin/ldd.fakechroot";
push @fakechrootsubst, "$dir/ischroot=/bin/true";
}
if (defined $ENV{FAKECHROOT_CMD_SUBST}
&& $ENV{FAKECHROOT_CMD_SUBST} ne "") {
push @fakechrootsubst, split /:/,
$ENV{FAKECHROOT_CMD_SUBST};
}
$ENV{FAKECHROOT_CMD_SUBST} = join ':', @fakechrootsubst;
}
if (defined $ENV{FAKECHROOT_EXCLUDE_PATH}
&& $ENV{FAKECHROOT_EXCLUDE_PATH} ne "") {
$ENV{FAKECHROOT_EXCLUDE_PATH}
= "$ENV{FAKECHROOT_EXCLUDE_PATH}:/dev:/proc:/sys";
} else {
$ENV{FAKECHROOT_EXCLUDE_PATH} = '/dev:/proc:/sys';
}
# workaround for long unix socket path if FAKECHROOT_BASE
# exceeds the limit of 108 bytes
$ENV{FAKECHROOT_AF_UNIX_PATH} = "/tmp";
{
my @ldsoconf = ('/etc/ld.so.conf');
opendir(my $dh, '/etc/ld.so.conf.d')
or error "Can't opendir(/etc/ld.so.conf.d): $!";
while (my $entry = readdir $dh) {
# skip the "." and ".." entries
next if $entry eq ".";
next if $entry eq "..";
next if $entry !~ /\.conf$/;
push @ldsoconf, "/etc/ld.so.conf.d/$entry";
}
closedir($dh);
my @ldlibpath = ();
if (defined $ENV{LD_LIBRARY_PATH}
&& $ENV{LD_LIBRARY_PATH} ne "") {
push @ldlibpath, (split /:/, $ENV{LD_LIBRARY_PATH});
}
# FIXME: workaround allowing installation of systemd should
# live in fakechroot, see #917920
push @ldlibpath, "/lib/systemd";
foreach my $fname (@ldsoconf) {
open my $fh, "<", $fname
or error "cannot open $fname for reading: $!";
while (my $line = <$fh>) {
next if $line !~ /^\//;
push @ldlibpath, $line;
}
close $fh;
}
$ENV{LD_LIBRARY_PATH} = join ':', @ldlibpath;
}
}
# make sure that APT_CONFIG is not set when executing anything
# inside the chroot
my @chrootcmd = ();
if ($options->{mode} eq 'proot') {
push @chrootcmd,
(
'proot', '--root-id',
'--bind=/dev', '--bind=/proc',
'--bind=/sys', "--rootfs=$options->{root}",
'--cwd=/'
);
} elsif (
any { $_ eq $options->{mode} }
('root', 'unshare', 'fakechroot')
) {
push @chrootcmd, ('/usr/sbin/chroot', $options->{root});
} else {
error "unknown mode: $options->{mode}";
}
# copy qemu-user-static binary into chroot or setup proot with
# --qemu
if (defined $options->{qemu}) {
if ($options->{mode} eq 'proot') {
push @chrootcmd, "--qemu=qemu-$options->{qemu}";
} elsif ($options->{mode} eq 'fakechroot') {
# The binfmt support on the outside is used, so qemu needs
# to know where it has to look for shared libraries
if (defined $ENV{QEMU_LD_PREFIX}
&& $ENV{QEMU_LD_PREFIX} ne "") {
$ENV{QEMU_LD_PREFIX}
= "$ENV{QEMU_LD_PREFIX}:$options->{root}";
} else {
$ENV{QEMU_LD_PREFIX} = $options->{root};
}
# Make sure that the fakeroot and fakechroot shared
# libraries exist for the right architecture
open my $fh, '-|', 'dpkg-architecture', '-a',
$options->{nativearch},
'-qDEB_HOST_MULTIARCH' // error "failed to fork(): $!";
chomp(
my $deb_host_multiarch = do { local $/; <$fh> }
);
close $fh;
if ($? != 0 or !$deb_host_multiarch) {
error "dpkg-architecture failed: $?";
}
my $fakechrootdir
= "/usr/lib/$deb_host_multiarch/fakechroot";
if (!-e "$fakechrootdir/libfakechroot.so") {
error "$fakechrootdir/libfakechroot.so doesn't exist."
. " Install libfakechroot:$options->{nativearch}"
. " outside the chroot";
}
my $fakerootdir
= "/usr/lib/$deb_host_multiarch/libfakeroot";
if (!-e "$fakerootdir/libfakeroot-sysv.so") {
error "$fakerootdir/libfakeroot-sysv.so doesn't exist."
. " Install libfakeroot:$options->{nativearch}"
. " outside the chroot";
}
# fakechroot only fills LD_LIBRARY_PATH with the
# directories of the host's architecture. We append the
# directories of the chroot architecture.
$ENV{LD_LIBRARY_PATH} .= ":$fakechrootdir:$fakerootdir";
} elsif (any { $_ eq $options->{mode} } ('root', 'unshare')) {
# other modes require a static qemu-user binary
my $qemubin = "/usr/bin/qemu-$options->{qemu}-static";
if (!-e $qemubin) {
error "cannot find $qemubin";
}
copy $qemubin, "$options->{root}/$qemubin"
or error "cannot copy $qemubin: $!";
# File::Copy does not retain permissions but on some
# platforms (like Travis CI) the binfmt interpreter must
# have the executable bit set or otherwise execve will
# fail with EACCES
chmod 0755, "$options->{root}/$qemubin"
or error "cannot chmod $qemubin: $!";
} else {
error "unknown mode: $options->{mode}";
}
}
# some versions of coreutils use the renameat2 system call in mv.
# This breaks certain versions of fakechroot and proot. Here we do
# a sanity check and warn the user in case things might break.
if (any { $_ eq $options->{mode} } ('fakechroot', 'proot')
and -e "$options->{root}/bin/mv") {
mkdir "$options->{root}/000-move-me"
or error "cannot create directory: $!";
my $ret = system @chrootcmd, '/bin/mv', '/000-move-me',
'/001-delete-me';
if ($ret != 0) {
if ($options->{mode} eq 'proot') {
info "the /bin/mv binary inside the chroot doesn't"
. " work under proot";
info "this is likely due to missing support for"
. " renameat2 in proot";
info
"see https://github.com/proot-me/PRoot/issues/147";
} else {
info "the /bin/mv binary inside the chroot doesn't"
. " work under fakechroot";
info "with certain versions of coreutils and glibc,"
. " this is due to missing support for renameat2 in"
. " fakechroot";
info
"see https://github.com/dex4er/fakechroot/issues/60";
}
info
"expect package post installation scripts not to work";
rmdir "$options->{root}/000-move-me"
or error "cannot rmdir: $!";
} else {
rmdir "$options->{root}/001-delete-me"
or error "cannot rmdir: $!";
}
}
# install the extracted packages properly
# we need --force-depends because dpkg does not take Pre-Depends
# into account and thus doesn't install them in the right order
# And the --predep-package option is broken: #539133
info "installing packages...";
run_chroot {
run_dpkg_progress({
ARGV => [
@chrootcmd, 'env',
'--unset=TMPDIR', 'dpkg',
'--install', '--force-depends'
],
PKGS => \@essential_pkgs,
});
}
$options;
# if the path-excluded option was added to the dpkg config,
# reinstall all packages
if (-e "$options->{root}/etc/dpkg/dpkg.cfg.d/99mmdebstrap") {
open(my $fh, '<',
"$options->{root}/etc/dpkg/dpkg.cfg.d/99mmdebstrap")
or error "cannot open /etc/dpkg/dpkg.cfg.d/99mmdebstrap: $!";
my $num_matches = grep /^path-exclude=/, <$fh>;
close $fh;
if ($num_matches > 0) {
# without --skip-same-version, dpkg will install the given
# packages even though they are already installed
info "re-installing packages because of path-exclude...";
run_dpkg_progress({
ARGV => [
@chrootcmd, 'env',
'--unset=TMPDIR', 'dpkg',
'--install', '--force-depends'
],
PKGS => \@essential_pkgs,
});
}
}
foreach my $deb (@essential_pkgs) {
unlink "$options->{root}/$deb"
or error "cannot unlink $deb: $!";
}
# run essential hooks
if ($options->{variant} ne 'custom') {
run_hooks('essential', $options);
}
if ($options->{variant} ne 'custom'
and scalar @pkgs_to_install > 0) {
# some packages have to be installed from the outside before
# anything can be installed from the inside.
#
# we do not need to install any *-archive-keyring packages
# inside the chroot prior to installing the packages, because
# the keyring is only used when doing "apt-get update" and that
# was already done at the beginning using key material from the
# outside. Since the apt cache is already filled and we are not
# calling "apt-get update" again, the keyring can be installed
# later during installation. But: if it's not installed during
# installation, then we might end up with a fully installed
# system without keyrings that are valid for its sources.list.
my @pkgs_to_install_from_outside;
# install apt if necessary
if ($options->{variant} ne 'apt') {
push @pkgs_to_install_from_outside, 'apt';
}
# since apt will be run inside the chroot, make sure that
# apt-transport-https and ca-certificates gets installed first
# if any mirror is a https URI
open(my $pipe_apt, '-|', 'apt-get', 'indextargets',
'--format', '$(URI)', 'Created-By: Packages')
or error "cannot start apt-get indextargets: $!";
while (my $uri = <$pipe_apt>) {
if ($uri =~ /^https:\/\//) {
# FIXME: support for https is part of apt >= 1.5
push @pkgs_to_install_from_outside,
'apt-transport-https';
push @pkgs_to_install_from_outside, 'ca-certificates';
last;
} elsif ($uri =~ /^tor(\+[a-z]+)*:\/\//) {
# tor URIs can be tor+http://, tor+https:// or even
# tor+mirror+file://
push @pkgs_to_install_from_outside,
'apt-transport-tor';
last;
}
}
close $pipe_apt;
$? == 0 or error "apt-get indextargets failed";
if (scalar @pkgs_to_install_from_outside > 0) {
info 'downloading '
. (join ', ', @pkgs_to_install_from_outside) . "...";
run_apt_progress({
ARGV => [
'apt-get', '--yes',
'-oApt::Get::Download-Only=true', 'install'
],
PKGS => [@pkgs_to_install_from_outside],
});
my @debs_to_install;
my $apt_archives = "/var/cache/apt/archives/";
opendir my $dh, "$options->{root}/$apt_archives"
or error "cannot read $apt_archives";
while (my $deb = readdir $dh) {
if ($deb !~ /\.deb$/) {
next;
}
$deb = "$apt_archives/$deb";
if (!-f "$options->{root}/$deb") {
next;
}
push @debs_to_install, $deb;
}
close $dh;
if (scalar @debs_to_install == 0) {
warning "nothing got downloaded -- maybe the packages"
. " were already installed?";
} else {
# we need --force-depends because dpkg does not take
# Pre-Depends into account and thus doesn't install
# them in the right order
info 'installing '
. (join ', ', @pkgs_to_install_from_outside) . "...";
run_dpkg_progress({
ARGV => [
@chrootcmd, 'env',
'--unset=TMPDIR', 'dpkg',
'--install', '--force-depends'
],
PKGS => \@debs_to_install,
});
foreach my $deb (@debs_to_install) {
unlink "$options->{root}/$deb"
or error "cannot unlink $deb: $!";
}
}
}
run_chroot {
info "installing remaining packages inside the chroot...";
run_apt_progress({
ARGV => [
@chrootcmd, 'env',
'--unset=APT_CONFIG', '--unset=TMPDIR',
'apt-get', '--yes',
'install'
],
PKGS => [@pkgs_to_install],
});
}
$options;
}
} else {
error "unknown variant: $options->{variant}";
}
} else {
error "unknown mode: $options->{mode}";
}
run_hooks('customize', $options);
# clean up temporary configuration file
unlink "$options->{root}/etc/apt/apt.conf.d/00mmdebstrap"
or error "failed to unlink /etc/apt/apt.conf.d/00mmdebstrap: $!";
info "cleaning package lists and apt cache...";
run_apt_progress({
ARGV => [
'apt-get', '--option',
'Dir::Etc::SourceList=/dev/null', '--option',
'Dir::Etc::SourceParts=/dev/null', 'update'
],
CHDIR => $options->{root},
});
run_apt_progress(
{ ARGV => ['apt-get', 'clean'], CHDIR => $options->{root} });
# apt since 1.6 creates the auxfiles directory. If apt inside the chroot
# is older than that, then it will not know how to clean it.
if (-e "$options->{root}/var/lib/apt/lists/auxfiles") {
rmdir "$options->{root}/var/lib/apt/lists/auxfiles"
or die "cannot rmdir /var/lib/apt/lists/auxfiles: $!";
}
if (defined $options->{qemu}
and any { $_ eq $options->{mode} } ('root', 'unshare')) {
unlink "$options->{root}/usr/bin/qemu-$options->{qemu}-static"
or error "cannot unlink /usr/bin/qemu-$options->{qemu}-static: $!";
}
# clean up certain files to make output reproducible
foreach my $fname (
'/var/log/dpkg.log', '/var/log/apt/history.log',
'/var/log/apt/term.log', '/var/log/alternatives.log',
'/var/cache/ldconfig/aux-cache', '/var/log/apt/eipp.log.xz'
) {
my $path = "$options->{root}$fname";
if (!-e $path) {
next;
}
unlink $path or error "cannot unlink $path: $!";
}
# remove any possible leftovers in /tmp but warn about it
if (-d "$options->{root}/tmp") {
opendir(my $dh, "$options->{root}/tmp")
or error "Can't opendir($options->{root}/tmp): $!";
while (my $entry = readdir $dh) {
# skip the "." and ".." entries
next if $entry eq ".";
next if $entry eq "..";
warning "deleting files in /tmp: $entry";
remove_tree("$options->{root}/tmp/$entry", { error => \my $err });
if (@$err) {
for my $diag (@$err) {
my ($file, $message) = %$diag;
if ($file eq '') { warning "general error: $message"; }
else { warning "problem unlinking $file: $message"; }
}
}
}
closedir($dh);
}
}
# messages from process inside unshared namespace to the outside
# openw -- open file for writing
# untar -- extract tar into directory
# write -- write data to last opened file or tar process
# close -- finish file writing or tar extraction
# adios -- last message and tear-down
# messages from process outside unshared namespace to the inside
# okthx -- success
sub checkokthx {
my $fh = shift;
my $ret = read($fh, my $buf, 2 + 5) // error "cannot read from socket: $!";
if ($ret == 0) { error "received eof on socket"; }
my ($len, $msg) = unpack("nA5", $buf);
if ($msg ne "okthx") { error "expected okthx but got: $msg"; }
if ($len != 0) { error "expected no payload but got $len bytes"; }
}
sub main() {
umask 022;
if (scalar @ARGV >= 7 && $ARGV[0] eq "--hook-helper") {
my $root = $ARGV[1];
my $mode = $ARGV[2];
my $hook = $ARGV[3];
my $qemu = $ARGV[4];
$verbosity_level = $ARGV[5];
my $command = $ARGV[6];
# unless we are in the setup hook (where there is no tar inside the
# chroot) we need to run tar on the inside because otherwise, possible
# absolute symlinks in the path given via --directory are not
# correctly resolved
#
# FIXME: the issue above can be fixed by a function that is able to
# resolve absolute symlinks even inside the chroot directory to a full
# path that is valid on the outside -- fakechroot and proot have their
# own reasons, see below
my @cmdprefix = ();
my @tarcmd = ('tar');
if ($hook eq 'setup') {
if ($mode eq 'proot') {
# since we cannot run tar inside the chroot under proot during
# the setup hook because the chroot is empty, we have to run
# tar from the outside, which leads to all files being owned
# by the user running mmdebstrap. To let the ownership
# information not be completely off, we force all files be
# owned by the root user.
push @tarcmd, '--owner=root', '--group=root';
}
} elsif (any { $_ eq $hook } ('essential', 'customize')) {
if ($mode eq 'fakechroot') {
# Fakechroot requires tar to run inside the chroot or
# otherwise absolute symlinks will include the path to the
# root directory
push @cmdprefix, '/usr/sbin/chroot', $root;
} elsif ($mode eq 'proot') {
# proot requires tar to run inside proot or otherwise
# permissions will be completely off
push @cmdprefix, 'proot', '--root-id', "--rootfs=$root",
'--cwd=/', "--qemu=$qemu";
} elsif (any { $_ eq $mode } ('root', 'chrootless', 'unshare')) {
push @cmdprefix, '/usr/sbin/chroot', $root;
} else {
error "unknown mode: $mode";
}
} else {
error "unknown hook: $hook";
}
if (any { $_ eq $command } ('copy-in', 'tar-in', 'upload')) {
if (scalar @ARGV < 9) {
error "copy-in and tar-in need at least one path on the"
. " outside and the output path inside the chroot";
}
my $outpath = $ARGV[-1];
for (my $i = 7 ; $i < $#ARGV ; $i++) {
# the right argument for tar's --directory argument depends on
# whether tar is called from inside the chroot or from the
# outside
my $directory;
if ($hook eq 'setup') {
$directory = "$root/$outpath";
} elsif (any { $_ eq $hook } ('essential', 'customize')) {
$directory = $outpath;
} else {
error "unknown hook: $hook";
}
# FIXME: here we would like to check if the path inside the
# chroot given by $directory actually exists but we cannot
# because we are missing a function that can resolve even
# paths including absolute symlinks to paths that are valid
# outside the chroot
my $fh;
if ($command eq 'upload') {
# open the requested file for writing
open $fh, '|-', @cmdprefix, 'sh', '-c', 'cat > "$1"',
'exec', $directory // error "failed to fork(): $!";
} else {
# open a tar process that extracts the tarfile that we
# supply it with on stdin to the output directory inside
# the chroot
open $fh, '|-', @cmdprefix, @tarcmd, '--directory',
$directory, '--extract', '--file',
'-' // error "failed to fork(): $!";
}
if ($command eq 'copy-in') {
# instruct the parent process to create a tarball of the
# requested path outside the chroot
debug "sending mktar";
print STDOUT (
pack("n", length $ARGV[$i]) . "mktar" . $ARGV[$i]);
} else {
# instruct parent process to open a tarball of the
# requested path outside the chroot for reading
debug "sending openr";
print STDOUT (
pack("n", length $ARGV[$i]) . "openr" . $ARGV[$i]);
}
STDOUT->flush();
debug "waiting for okthx";
checkokthx \*STDIN;
# handle "write" messages from the parent process and feed
# their payload into the tar process until a "close" message
# is encountered
while (1) {
# receive the next message
my $ret = read(STDIN, my $buf, 2 + 5)
// error "cannot read from socket: $!";
if ($ret == 0) {
error "received eof on socket";
}
my ($len, $msg) = unpack("nA5", $buf);
debug "received message: $msg";
if ($msg eq "close") {
# finish the loop
if ($len != 0) {
error "expected no payload but got $len bytes";
}
debug "sending okthx";
print STDOUT (pack("n", 0) . "okthx")
or error "cannot write to socket: $!";
STDOUT->flush();
last;
} elsif ($msg ne "write") {
# we should not receive this message at this point
print STDOUT (pack("n", 0) . "error")
or error "cannot write to socket: $!";
STDOUT->flush();
error "expected write but got: $msg";
}
# read the payload
my $content;
{
my $ret = read(STDIN, $content, $len)
// error "error cannot read from socket: $!";
if ($ret == 0) {
error "received eof on socket";
}
}
# write the payload to the tar process
print $fh $content
or error "cannot write to tar process: $!";
debug "sending okthx";
print STDOUT (pack("n", 0) . "okthx")
or error "cannot write to socket: $!";
STDOUT->flush();
}
close $fh;
if ($command ne 'upload' and $? != 0) {
error "tar failed";
}
}
} elsif (any { $_ eq $command } ('copy-out', 'tar-out', 'download')) {
if (scalar @ARGV < 9) {
error "copy-out needs at least one path inside the chroot and"
. " the output path on the outside";
}
my $outpath = $ARGV[-1];
for (my $i = 7 ; $i < $#ARGV ; $i++) {
# the right argument for tar's --directory argument depends on
# whether tar is called from inside the chroot or from the
# outside
my $directory;
if ($hook eq 'setup') {
$directory = "$root/$ARGV[$i]";
} elsif (any { $_ eq $hook } ('essential', 'customize')) {
$directory = $ARGV[$i];
} else {
error "unknown hook: $hook";
}
# FIXME: here we would like to check if the path inside the
# chroot given by $directory actually exists but we cannot
# because we are missing a function that can resolve even
# paths including absolute symlinks to paths that are valid
# outside the chroot
my $fh;
if ($command eq 'download') {
# open the requested file for reading
open $fh, '-|', @cmdprefix, 'sh', '-c', 'cat "$1"',
'exec', $directory // error "failed to fork(): $!";
} else {
# Open a tar process that creates a tarfile of everything
# in the requested directory inside the chroot and writes
# it to stdout. To emulate the behaviour of cp, change to
# the dirname of the requested path first.
open $fh, '-|', @cmdprefix, @tarcmd, '--directory',
dirname($directory), '--create', '--file', '-',
basename($directory) // error "failed to fork(): $!";
}
if ($command eq 'copy-out') {
# instruct the parent process to extract a tarball to a
# certain path outside the chroot
debug "sending untar";
print STDOUT (
pack("n", length $outpath) . "untar" . $outpath);
} else {
# instruct parent process to open a tarball of the
# requested path outside the chroot for writing
debug "sending openw";
print STDOUT (
pack("n", length $outpath) . "openw" . $outpath);
}
STDOUT->flush();
debug "waiting for okthx";
checkokthx \*STDIN;
# read from the tar process and send as payload to the parent
# process
while (1) {
# read from tar
my $ret = read($fh, my $cont, 4096)
// error "cannot read from pipe: $!";
if ($ret == 0) { last; }
debug "sending write";
# send to parent
print STDOUT pack("n", $ret) . "write" . $cont;
STDOUT->flush();
debug "waiting for okthx";
checkokthx \*STDIN;
if ($ret < 4096) { last; }
}
# signal to the parent process that we are done
debug "sending close";
print STDOUT pack("n", 0) . "close";
STDOUT->flush();
debug "waiting for okthx";
checkokthx \*STDIN;
close $fh;
if ($command ne 'download' and $? != 0) {
error "tar failed";
}
}
} else {
error "unknown command: $command";
}
exit 0;
}
my $mtime = time;
if (exists $ENV{SOURCE_DATE_EPOCH}) {
$mtime = $ENV{SOURCE_DATE_EPOCH} + 0;
}
$ENV{DEBIAN_FRONTEND} = 'noninteractive';
$ENV{DEBCONF_NONINTERACTIVE_SEEN} = 'true';
$ENV{LC_ALL} = 'C.UTF-8';
$ENV{LANGUAGE} = 'C.UTF-8';
$ENV{LANG} = 'C.UTF-8';
# copy ARGV because getopt modifies it
my @ARGVORIG = @ARGV;
chomp(my $hostarch = `dpkg --print-architecture`);
my $options = {
components => ["main"],
variant => "important",
include => [],
architectures => [$hostarch],
mode => 'auto',
dpkgopts => [],
aptopts => [],
apttrusted => "/etc/apt/trusted.gpg",
apttrustedparts => "/etc/apt/trusted.gpg.d",
noop => [],
setup_hook => [],
essential_hook => [],
customize_hook => [],
};
my $logfile = undef;
Getopt::Long::Configure('default', 'bundling', 'auto_abbrev',
'ignore_case_always');
GetOptions(
'h|help' => sub { pod2usage(-exitval => 0, -verbose => 1) },
'man' => sub { pod2usage(-exitval => 0, -verbose => 2) },
'version' => sub { print STDOUT "mmdebstrap $VERSION\n"; exit 0; },
'components=s@' => \$options->{components},
'variant=s' => \$options->{variant},
'include=s@' => \$options->{include},
'architectures=s@' => \$options->{architectures},
'mode=s' => \$options->{mode},
'dpkgopt=s@' => \$options->{dpkgopts},
'aptopt=s@' => \$options->{aptopts},
'keyring=s' => sub {
my ($opt_name, $opt_value) = @_;
if ($opt_value =~ /"/) {
error "--keyring: apt cannot handle paths with double quotes:"
. " $opt_value";
}
if (!-e $opt_value) {
error "keyring \"$opt_value\" does not exist";
}
my $abs_path = abs_path($opt_value);
if (!defined $abs_path) {
error "unable to get absolute path of --keyring: $opt_value";
}
# since abs_path resolved all symlinks for us, we can now test
# what the actual target actually is
if (-d $opt_value) {
$options->{apttrustedparts} = $opt_value;
} else {
$options->{apttrusted} = $opt_value;
}
},
's|silent' => sub { $verbosity_level = 0; },
'q|quiet' => sub { $verbosity_level = 0; },
'v|verbose' => sub { $verbosity_level = 2; },
'd|debug' => sub { $verbosity_level = 3; },
'logfile=s' => \$logfile,
# no-op options so that mmdebstrap can be used with
# sbuild-createchroot --debootstrap=mmdebstrap
'resolve-deps' => sub { push @{ $options->{noop} }, 'resolve-deps'; },
'merged-usr' => sub { push @{ $options->{noop} }, 'merged-usr'; },
'no-merged-usr' =>
sub { push @{ $options->{noop} }, 'no-merged-usr'; },
'force-check-gpg' =>
sub { push @{ $options->{noop} }, 'force-check-gpg'; },
# hook options are hidden until I'm happy with them
'setup-hook=s@' => \$options->{setup_hook},
'essential-hook=s@' => \$options->{essential_hook},
'customize-hook=s@' => \$options->{customize_hook},
) or pod2usage(-exitval => 2, -verbose => 1);
if (defined($logfile)) {
open(STDERR, '>', $logfile) or error "cannot open $logfile: $!";
}
foreach my $arg (@{ $options->{noop} }) {
info "The option --$arg is a no-op. It only exists for compatibility"
. " with some debootstrap wrappers.";
}
my @valid_variants = (
'extract', 'custom', 'essential', 'apt',
'required', 'minbase', 'buildd', 'important',
'debootstrap', '-', 'standard'
);
if (none { $_ eq $options->{variant} } @valid_variants) {
error "invalid variant. Choose from " . (join ', ', @valid_variants);
}
# debootstrap and - are an alias for important
if (any { $_ eq $options->{variant} } ('-', 'debootstrap')) {
$options->{variant} = 'important';
}
if ($options->{variant} eq 'essential'
and scalar @{ $options->{include} } > 0) {
warning "cannot install extra packages with variant essential because"
. " apt is missing";
}
# fakeroot is an alias for fakechroot
if ($options->{mode} eq 'fakeroot') {
$options->{mode} = 'fakechroot';
}
# sudo is an alias for root
if ($options->{mode} eq 'sudo') {
$options->{mode} = 'root';
}
my @valid_modes
= ('auto', 'root', 'unshare', 'fakechroot', 'proot', 'chrootless');
if (none { $_ eq $options->{mode} } @valid_modes) {
error "invalid mode. Choose from " . (join ', ', @valid_modes);
}
my $check_fakechroot_running = sub {
# test if we are inside fakechroot already
# We fork a child process because setting FAKECHROOT_DETECT seems to
# be an irreversible operation for fakechroot.
my $pid = open my $rfh, '-|' // error "failed to fork(): $!";
if ($pid == 0) {
# with the FAKECHROOT_DETECT environment variable set, any program
# execution will be replaced with the output "fakeroot [version]"
$ENV{FAKECHROOT_DETECT} = 0;
exec 'echo', 'If fakechroot is running, this will not be printed';
}
my $content = do { local $/; <$rfh> };
waitpid $pid, 0;
my $result = 0;
if ($? == 0 and $content =~ /^fakechroot \d\.\d+$/) {
$result = 1;
}
return $result;
};
# figure out the mode to use or test whether the chosen mode is legal
if ($options->{mode} eq 'auto') {
if (&{$check_fakechroot_running}()) {
# if mmdebstrap is executed inside fakechroot, then we assume the
# user expects fakechroot mode
$options->{mode} = 'fakechroot';
} elsif ($EFFECTIVE_USER_ID == 0) {
# if mmdebstrap is executed as root, we assume the user wants root
# mode
$options->{mode} = 'root';
} elsif (test_unshare(0)) {
# otherwise, unshare mode is our best option if test_unshare()
# succeeds
$options->{mode} = 'unshare';
} elsif (system('fakechroot --version>/dev/null') == 0) {
# the next fallback is fakechroot
# exec ourselves again but within fakechroot
my @prefix = ();
if ($is_covering) {
@prefix = ($EXECUTABLE_NAME, '-MDevel::Cover=-silent,-nogcov');
}
exec 'fakechroot', 'fakeroot', @prefix, $PROGRAM_NAME, @ARGVORIG;
} elsif (system('proot --version>/dev/null') == 0) {
# and lastly, proot
$options->{mode} = 'proot';
} else {
error "unable to pick chroot mode automatically";
}
info "automatically chosen mode: $options->{mode}";
} elsif ($options->{mode} eq 'root') {
if ($EFFECTIVE_USER_ID != 0) {
error "need to be root";
}
} elsif ($options->{mode} eq 'proot') {
if (system('proot --version>/dev/null') != 0) {
error "need working proot binary";
}
} elsif ($options->{mode} eq 'fakechroot') {
if (&{$check_fakechroot_running}()) {
# fakechroot is already running
} elsif (system('fakechroot --version>/dev/null') != 0) {
error "need working fakechroot binary";
} else {
# exec ourselves again but within fakechroot
my @prefix = ();
if ($is_covering) {
@prefix = ($EXECUTABLE_NAME, '-MDevel::Cover=-silent,-nogcov');
}
exec 'fakechroot', 'fakeroot', @prefix, $PROGRAM_NAME, @ARGVORIG;
}
} elsif ($options->{mode} eq 'unshare') {
if (!test_unshare(1)) {
my $procfile = '/proc/sys/kernel/unprivileged_userns_clone';
open(my $fh, '<', $procfile)
or error "failed to open $procfile: $!";
chomp(
my $content = do { local $/; <$fh> }
);
close($fh);
if ($content ne "1") {
info "/proc/sys/kernel/unprivileged_userns_clone is set to"
. " $content";
info "Try running:";
info " sudo sysctl -w kernel.unprivileged_userns_clone=1";
info "or permanently enable unprivileged usernamespaces by"
. " putting the setting into /etc/sysctl.d/";
info "see https://bugs.debian.org/cgi-bin/"
. "bugreport.cgi?bug=898446";
}
exit 1;
}
} elsif ($options->{mode} eq 'chrootless') {
# nothing to do
} else {
error "unknown mode: $options->{mode}";
}
my @architectures = ();
foreach my $archs (@{ $options->{architectures} }) {
foreach my $arch (split /[,\s]+/, $archs) {
# strip leading and trailing whitespace
$arch =~ s/^\s+|\s+$//g;
# skip if the remainder is an empty string
if ($arch eq '') {
next;
}