Re: [pmg-devel] [PATCH api 2/8] add PMG::CertHelpers module

[Wolfgang Bumiller <w.bumiller@proxmox.com>]

On Thu, Mar 11, 2021 at 11:05:21AM +0100, Dominik Csapak wrote:
> comments inline
> 
> On 3/9/21 3:13 PM, Wolfgang Bumiller wrote:
> > Contains helpers to update certificates and provide locking
> > for certificates and when accessing acme accounts.
> > 
> > Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
> > ---
> >   src/Makefile           |   1 +
> >   src/PMG/CertHelpers.pm | 180 +++++++++++++++++++++++++++++++++++++++++
> >   2 files changed, 181 insertions(+)
> >   create mode 100644 src/PMG/CertHelpers.pm
> > 
> > diff --git a/src/Makefile b/src/Makefile
> > index 8891a3c..c1d4812 100644
> > --- a/src/Makefile
> > +++ b/src/Makefile
> > @@ -55,6 +55,7 @@ LIBSOURCES =				\
> >   	PMG/HTMLMail.pm			\
> >   	PMG/ModGroup.pm			\
> >   	PMG/SMTPPrinter.pm		\
> > +	PMG/CertHelpers.pm		\
> >   	PMG/Config.pm			\
> >   	PMG/Cluster.pm			\
> >   	PMG/ClusterConfig.pm		\
> > diff --git a/src/PMG/CertHelpers.pm b/src/PMG/CertHelpers.pm
> > new file mode 100644
> > index 0000000..2cf8a4e
> > --- /dev/null
> > +++ b/src/PMG/CertHelpers.pm
> > @@ -0,0 +1,180 @@
> > +package PMG::CertHelpers;
> > +
> > +use strict;
> > +use warnings;
> > +
> > +use PVE::Certificate;
> > +use PVE::JSONSchema;
> > +use PVE::Tools;
> > +
> > +use constant {
> > +    API_CERT => '/etc/pmg/pmg-api.pem',
> > +    SMTP_CERT => '/etc/pmg/pmg-tls.pem',
> > +};
> > +
> > +my $account_prefix = '/etc/pmg/acme';
> > +
> > +# TODO: Move `pve-acme-account-name` to common and reuse instead of this.
> > +PVE::JSONSchema::register_standard_option('pmg-acme-account-name', {
> > +    description => 'ACME account config file name.',
> > +    type => 'string',
> > +    format => 'pve-configid',
> > +    format_description => 'name',
> > +    optional => 1,
> > +    default => 'default',
> > +});
> > +
> > +PVE::JSONSchema::register_standard_option('pmg-acme-account-contact', {
> > +    type => 'string',
> > +    format => 'email-list',
> > +    description => 'Contact email addresses.',
> > +});
> > +
> > +PVE::JSONSchema::register_standard_option('pmg-acme-directory-url', {
> > +    type => 'string',
> > +    description => 'URL of ACME CA directory endpoint.',
> > +    pattern => '^https?://.*',
> > +});
> > +
> > +PVE::JSONSchema::register_format('pmg-certificate-type', sub {
> > +    my ($type, $noerr) = @_;
> > +
> > +    if ($type =~ /^(?: api | smtp )$/x) {
> > +	return $type;
> > +    }
> > +    return undef if $noerr;
> > +    die "value '$type' does not look like a valid certificate type\n";
> > +});
> > +
> > +PVE::JSONSchema::register_standard_option('pmg-certificate-type', {
> > +    type => 'string',
> > +    description => 'The TLS certificate type (API or SMTP certificate).',
> > +    enum => ['api', 'smtp'],
> > +});
> 
> i get why you did the format and the option (you need it once as a '-list')
> but would it not have been possible to reuse the format instead
> of redefining the enum?

Yeah I suppose that works

> or only using the enum as variable defined somewhere?

(or at least that will)

> feels weird to have a format + option that do basically
> the same thing

I know

> 
> > +
> > +PVE::JSONSchema::register_format('pmg-acme-domain', sub {
> > +    my ($domain, $noerr) = @_;
> > +
> > +    my $label = qr/[a-z0-9][a-z0-9_-]*/i;
> > +
> > +    return $domain if $domain =~ /^$label(?:\.$label)+$/;
> > +    return undef if $noerr;
> > +    die "value '$domain' does not look like a valid domain name!\n";
> > +});
> > +
> > +PVE::JSONSchema::register_format('pmg-acme-alias', sub {
> > +    my ($alias, $noerr) = @_;
> > +
> > +    my $label = qr/[a-z0-9_][a-z0-9_-]*/i;
> > +
> > +    return $alias if $alias =~ /^$label(?:\.$label)+$/;
> > +    return undef if $noerr;
> > +    die "value '$alias' does not look like a valid alias name!\n";
> > +});
> 
> could we not reuse the '-domain' format here ?
> i know the error message would be different then, but it is still a domain?
> 
> if not, we could refactor the regexes though

-alias was specifically introduced to allow using underscore prefixes.
(See pve-manager b3d421707)

> 
> > +
> > +my $local_cert_lock = '/var/lock/pmg-certs.lock';
> > +my $local_acme_lock = '/var/lock/pmg-acme.lock';
> > +
> > +sub cert_path : prototype($) {
> > +    my ($type) = @_;
> > +    if ($type eq 'api') {
> > +	return API_CERT;
> > +    } elsif ($type eq 'smtp') {
> > +	return SMTP_CERT;
> > +    } else {
> > +	die "unknown certificate type '$type'\n";
> > +    }
> > +}
> > +
> > +sub cert_lock {
> > +    my ($timeout, $code, @param) = @_;
> > +
> > +    my $res = PVE::Tools::lock_file($local_cert_lock, $timeout, $code, @param);
> > +    die $@ if $@;
> > +    return $res;
> > +}
> > +
> > +sub set_cert_file {
> > +    my ($cert, $cert_path, $force) = @_;
> > +
> > +    my ($old_cert, $info);
> > +
> > +    my $cert_path_old = "${cert_path}.old";
> > +
> > +    die "Custom certificate file exists but force flag is not set.\n"
> > +	if !$force && -e $cert_path;
> > +
> > +    PVE::Tools::file_copy($cert_path, $cert_path_old) if -e $cert_path;
> > +
> > +    eval {
> > +	my $gid = undef;
> > +	if ($cert_path eq &API_CERT) {
> > +	    $gid = getgrnam('www-data') ||
> > +		die "user www-data not in group file\n";
> > +	}
> > +
> > +	if (defined($gid)) {
> > +	    my $cert_path_tmp = "${cert_path}.tmp";
> > +	    PVE::Tools::file_set_contents($cert_path_tmp, $cert, 0640);
> > +	    if (!chown(-1, $gid, $cert_path_tmp)) {
> > +		my $msg =
> > +		    "failed to change group ownership of '$cert_path_tmp' to www-data ($gid): $!\n";
> > +		unlink($cert_path_tmp);
> > +		die $msg;
> > +	    }
> > +	    if (!rename($cert_path_tmp, $cert_path)) {
> > +		my $msg =
> > +		    "failed to rename '$cert_path_tmp' to '$cert_path': $!\n";
> > +		unlink($cert_path_tmp);
> > +		die $msg;
> > +	    }
> > +	} else {
> > +	    PVE::Tools::file_set_contents($cert_path, $cert, 0600);
> > +	}
> > +
> > +	$info = PVE::Certificate::get_certificate_info($cert_path);
> > +    };
> > +    my $err = $@;
> > +
> > +    if ($err) {
> > +	if (-e $cert_path_old) {
> > +	    eval {
> > +		warn "Attempting to restore old certificate file..\n";
> > +		PVE::Tools::file_copy($cert_path_old, $cert_path);
> > +	    };
> > +	    warn "$@\n" if $@;
> > +	}
> > +	die "Setting certificate files failed - $err\n"
> > +    }
> > +
> > +    unlink $cert_path_old;
> > +
> > +    return $info;
> > +}
> > +
> > +sub lock_acme {
> > +    my ($account_name, $timeout, $code, @param) = @_;
> > +
> > +    my $file = "$local_acme_lock.$account_name";
> > +
> > +    return PVE::Tools::lock_file($file, $timeout, $code, @param);
> > +}
> > +
> 
> is there a special reason why you die $@ if $@ above in cert_lock
> but not here?
> 
> afaics, you do it manually in the later patches always anyway

That's just lock api madness... will fix.