--- /dev/null
+package PVE::ACME;
+
+use strict;
+use warnings;
+
+use POSIX;
+
+use Data::Dumper;
+use Date::Parse;
+use MIME::Base64 qw(encode_base64url);
+use File::Path qw(make_path);
+use JSON;
+use Digest::SHA qw(sha256 sha256_hex);
+
+use HTTP::Request;
+use LWP::UserAgent;
+
+use Crypt::OpenSSL::RSA;
+
+use PVE::Certificate;
+use PVE::Tools qw(
+file_set_contents
+file_get_contents
+);
+
+Crypt::OpenSSL::RSA->import_random_seed();
+
+my $LETSENCRYPT_STAGING = 'https://acme-staging-v02.api.letsencrypt.org/directory';
+
+### ACME library (compatible with Let's Encrypt v2 API)
+#
+# sample usage:
+#
+# 1) my $acme = PVE::ACME->new('path/to/account.json', 'API directory URL');
+# 2) $acme->init(4096); # generate account key
+# 4) my $tos_url = $acme->get_meta()->{termsOfService}; # optional, display if applicable
+# 5) $acme->new_account($tos_url, contact => ['mailto:example@example.com']);
+#
+# 1) my $acme = PVE::ACME->new('path/to/account.json', 'API directory URL');
+# 2) $acme->load();
+# 3) my ($order_url, $order) = $acme->new_order(['foo.example.com', 'bar.example.com']);
+# 4) # repeat a-f for each $auth_url in $order->{authorizations}
+# a) my $authorization = $acme->get_authorization($auth_url);
+# b) # pick $challenge from $authorization->{challenges} according to desired type
+# c) my $key_auth = $acme->key_authorization($challenge->{token});
+# d) # setup challenge validation according to specification
+# e) $acme->request_challenge_validation($challenge->{url}, $key_auth);
+# f) # poll $acme->get_authorization($auth_url) until status is 'valid'
+# 5) # generate CSR in PEM format
+# 6) $acme->finalize_order($order, $csr);
+# 7) # poll $acme->get_order($order_url) until status is 'valid'
+# 8) my $cert = $acme->get_certificate($order);
+# 9) # $key is path to key file, $cert contains PEM-encoded certificate chain
+#
+# 1) my $acme = PVE::ACME->new('path/to/account.json', 'API directory URL');
+# 2) $acme->load();
+# 3) $acme->revoke_certificate($cert);
+
+# Tools
+sub encode($) { # acme requires 'base64url' encoding
+ return encode_base64url($_[0]);
+}
+
+sub tojs($;%) { # shortcut for to_json with utf8=>1
+ my ($data, %data) = @_;
+ return to_json($data, { utf8 => 1, %data });
+}
+
+sub fromjs($) {
+ return from_json($_[0]);
+}
+
+sub fatal($$;$$) {
+ my ($self, $msg, $dump, $noerr) = @_;
+
+ warn Dumper($dump), "\n" if $self->{debug} && $dump;
+ if ($noerr) {
+ warn "$msg\n";
+ } else {
+ die "$msg\n";
+ }
+}
+
+# Implementation
+
+# $path: account JSON file
+# $directory: the ACME directory URL used to find method URLs
+sub new($$$) {
+ my ($class, $path, $directory) = @_;
+
+ $directory //= $LETSENCRYPT_STAGING;
+
+ my $ua = LWP::UserAgent->new();
+ $ua->env_proxy();
+ $ua->agent('pve-acme/0.1');
+ $ua->protocols_allowed(['https']);
+
+ my $self = {
+ ua => $ua,
+ path => $path,
+ directory => $directory,
+ nonce => undef,
+ key => undef,
+ location => undef,
+ account => undef,
+ tos => undef,
+ };
+
+ return bless $self, $class;
+}
+
+# RS256: PKCS#1 padding, no OAEP, SHA256
+my $configure_key = sub {
+ my ($key) = @_;
+ $key->use_pkcs1_padding();
+ $key->use_sha256_hash();
+};
+
+# Create account key with $keybits bits
+# use instead of load, overwrites existing account JSON file!
+sub init {
+ my ($self, $keybits) = @_;
+ die "Already have a key\n" if defined($self->{key});
+ $keybits //= 4096;
+ my $key = Crypt::OpenSSL::RSA->generate_key($keybits);
+ $configure_key->($key);
+ $self->{key} = $key;
+ $self->save();
+}
+
+my @SAVED_VALUES = qw(location account tos debug directory);
+# Serialize persistent parts of $self to $self->{path} as JSON
+sub save {
+ my ($self) = @_;
+ my $o = {};
+ my $keystr;
+ if (my $key = $self->{key}) {
+ $keystr = $key->get_private_key_string();
+ $o->{key} = $keystr;
+ }
+ for my $k (@SAVED_VALUES) {
+ my $v = $self->{$k} // next;
+ $o->{$k} = $v;
+ }
+ # pretty => 1 for readability
+ # canonical => 1 to reduce churn
+ file_set_contents($self->{path}, tojs($o, pretty => 1, canonical => 1));
+}
+
+# Load serialized account JSON file into $self
+sub load {
+ my ($self) = @_;
+ return if $self->{loaded};
+ $self->{loaded} = 1;
+ my $raw = file_get_contents($self->{path});
+ if ($raw =~ m/^(.*)$/s) { $raw = $1; } # untaint
+ my $data = fromjs($raw);
+ $self->{$_} = $data->{$_} for @SAVED_VALUES;
+ if (defined(my $keystr = $data->{key})) {
+ my $key = Crypt::OpenSSL::RSA->new_private_key($keystr);
+ $configure_key->($key);
+ $self->{key} = $key;
+ }
+}
+
+# The 'jwk' object needs the key type, key parameters and the usage,
+# except for when we want to take the JWK-Thumbprint, then the usage
+# must not be included.
+sub jwk {
+ my ($self, $pure) = @_;
+ my $key = $self->{key}
+ or die "No key was generated yet\n";
+ my ($n, $e) = $key->get_key_parameters();
+ return {
+ kty => 'RSA',
+ ($pure ? () : (use => 'sig')), # for thumbprints
+ n => encode($n->to_bin),
+ e => encode($e->to_bin),
+ };
+}
+
+# The thumbprint is a sha256 hash of the lexicographically sorted (iow.
+# canonical) condensed json string of the JWK object which gets base64url
+# encoded.
+sub jwk_thumbprint {
+ my ($self) = @_;
+ my $jwk = $self->jwk(1); # $pure = 1
+ return encode(sha256(tojs($jwk, canonical=>1))); # canonical sorts
+}
+
+# A key authorization string in acme is a challenge token dot-connected with
+# a JWK Thumbprint. You put the base64url encoded sha256-hash of this string
+# into the DNS TXT record.
+sub key_authorization {
+ my ($self, $token) = @_;
+ return $token .'.'. $self->jwk_thumbprint();
+}
+
+# JWS signing using the RS256 alg (RSA/SHA256).
+sub jws {
+ my ($self, $use_jwk, $data, $url) = @_;
+ my $key = $self->{key}
+ or die "No key was generated yet\n";
+
+ my $payload = $data ne '' ? encode(tojs($data)) : $data;
+
+ if (!defined($self->{nonce})) {
+ my $method = $self->_method('newNonce');
+ $self->do(GET => $method);
+ }
+
+ # The acme protocol requires the actual request URL be in the protected
+ # header. There is no unprotected header.
+ my $protected = {
+ alg => 'RS256',
+ url => $url,
+ nonce => $self->{nonce} // die "missing nonce\n"
+ };
+
+ # header contains either
+ # - kid, reference to account URL
+ # - jwk, key itself
+ # the latter is only allowed for
+ # - creating accounts (no account URL yet)
+ # - revoking certificates with the certificate key instead of account key
+ if ($use_jwk) {
+ $protected->{jwk} = $self->jwk();
+ } else {
+ $protected->{kid} = $self->{location};
+ }
+
+ $protected = encode(tojs($protected));
+
+ my $signdata = "$protected.$payload";
+ my $signature = encode($key->sign($signdata));
+
+ return {
+ protected => $protected,
+ payload => $payload,
+ signature => $signature,
+ };
+}
+
+sub __get_result {
+ my ($resp, $code, $plain) = @_;
+
+ die "expected code '$code', received '".$resp->code."'\n"
+ if $resp->code != $code;
+
+ return $plain ? $resp->decoded_content : fromjs($resp->decoded_content);
+}
+
+# Get the list of method URLs and query the directory if we have to.
+sub __get_methods {
+ my ($self) = @_;
+ if (my $methods = $self->{methods}) {
+ return $methods;
+ }
+ my $r = $self->do(GET => $self->{directory});
+ my $methods = __get_result($r, 200);
+ $self->fatal("unable to decode methods returned by directory - $@", $r) if $@;
+ return ($self->{methods} = $methods);
+}
+
+# Get a method, causing the directory to be queried first if necessary.
+sub _method {
+ my ($self, $method) = @_;
+ my $methods = $self->__get_methods();
+ my $url = $methods->{$method}
+ or die "no such method: $method\n";
+ return $url;
+}
+
+# Get $self->{account} with an error if we don't have one yet.
+sub _account {
+ my ($self) = @_;
+ my $account = $self->{account}
+ // die "no account loaded\n";
+ return wantarray ? ($account, $self->{location}) : $account;
+}
+
+# debugging info
+sub list_methods {
+ my ($self) = @_;
+ my $methods = $self->__get_methods();
+ if (my $meta = $methods->{meta}) {
+ print("(meta): $_ : $meta->{$_}\n") for sort keys %$meta;
+ }
+ print("$_ : $methods->{$_}\n") for sort grep {$_ ne 'meta'} keys %$methods;
+}
+
+# return (optional) meta directory entry.
+# this is public because it might contain the ToS, which should be displayed
+# and agreed to before creating an account
+sub get_meta {
+ my ($self) = @_;
+ my $methods = $self->__get_methods();
+ return $methods->{meta};
+}
+
+# Common code between new_account and update_account
+sub __new_account {
+ my ($self, $expected_code, $url, $new, %info) = @_;
+ my $req = {
+ %info,
+ };
+ my $r = $self->do(POST => $url, $req, $new);
+ eval {
+ my $account = __get_result($r, $expected_code);
+ if (!defined($self->{location})) {
+ my $account_url = $r->header('Location')
+ or die "did not receive an account URL\n";
+ $self->{location} = $account_url;
+ }
+ $self->{account} = $account;
+ $self->save();
+ };
+ $self->fatal("POST to '$url' failed - $@", $r) if $@;
+ return $self->{account};
+}
+
+# Create a new account using data in %info.
+# Optionally pass $tos_url to agree to the given Terms of Service
+# POST to newAccount endpoint
+# Expects a '201 Created' reply
+# Saves and returns the account data
+sub new_account {
+ my ($self, $tos_url, %info) = @_;
+ my $url = $self->_method('newAccount');
+
+ if ($tos_url) {
+ $self->{tos} = $tos_url;
+ $info{termsOfServiceAgreed} = JSON::true;
+ }
+
+ return $self->__new_account(201, $url, 1, %info);
+}
+
+# Update existing account with new %info
+# POST to account URL
+# Expects a '200 OK' reply
+# Saves and returns updated account data
+sub update_account {
+ my ($self, %info) = @_;
+ my (undef, $url) = $self->_account;
+
+ return $self->__new_account(200, $url, 0, %info);
+}
+
+# Retrieves existing account information
+# POST to account URL with empty body!
+# Expects a '200 OK' reply
+# Saves and returns updated account data
+sub get_account {
+ my ($self) = @_;
+ return $self->update_account();
+}
+
+# Start a new order for one or more domains
+# POST to newOrder endpoint
+# Expects a '201 Created' reply
+# returns order URL and parsed order object, including authorization and finalize URLs
+sub new_order {
+ my ($self, $domains) = @_;
+
+ my $url = $self->_method('newOrder');
+ my $req = {
+ identifiers => [ map { { type => 'dns', value => $_ } } @$domains ],
+ };
+
+ my $r = $self->do(POST => $url, $req);
+ my ($order_url, $order);
+ eval {
+ $order_url = $r->header('Location')
+ or die "did not receive an order URL\n";
+ $order = __get_result($r, 201)
+ };
+ $self->fatal("POST to '$url' failed - $@", $r) if $@;
+ return ($order_url, $order);
+}
+
+# Finalize order after all challenges have been validated
+# POST to order's finalize URL
+# Expects a '200 OK' reply
+# returns (potentially updated) order object
+sub finalize_order {
+ my ($self, $order, $csr) = @_;
+
+ my $req = {
+ csr => encode($csr),
+ };
+ my $r = $self->do(POST => $order->{finalize}, $req);
+ my $return = eval { __get_result($r, 200); };
+ $self->fatal("POST to '$order->{finalize}' failed - $@", $r) if $@;
+ return $return;
+}
+
+# Get order status
+# GET-as-POST to order URL
+# Expects a '200 OK' reply
+# returns order object
+sub get_order {
+ my ($self, $order_url) = @_;
+ my $r = $self->do(POST => $order_url, '');
+ my $return = eval { __get_result($r, 200); };
+ $self->fatal("POST of '$order_url' failed - $@", $r) if $@;
+ return $return;
+}
+
+# Gets authorization object
+# GET-as-POST to authorization URL
+# Expects a '200 OK' reply
+# returns authorization object, including challenges array
+sub get_authorization {
+ my ($self, $auth_url) = @_;
+
+ my $r = $self->do(POST => $auth_url, '');
+ my $return = eval { __get_result($r, 200); };
+ $self->fatal("POST of '$auth_url' failed - $@", $r) if $@;
+ return $return;
+}
+
+# Deactivates existing authorization
+# POST to authorization URL
+# Expects a '200 OK' reply
+# returns updated authorization object
+sub deactivate_authorization {
+ my ($self, $auth_url) = @_;
+
+ my $req = {
+ status => 'deactivated',
+ };
+ my $r = $self->do(POST => $auth_url, $req);
+ my $return = eval { __get_result($r, 200); };
+ $self->fatal("POST to '$auth_url' failed - $@", $r) if $@;
+ return $return;
+}
+
+# Get certificate
+# GET-as-POST to order's certificate URL
+# Expects a '200 OK' reply
+# returns certificate chain in PEM format
+sub get_certificate {
+ my ($self, $order) = @_;
+
+ $self->fatal("no certificate URL available (yet?)", $order)
+ if !$order->{certificate};
+
+ my $r = $self->do(POST => $order->{certificate}, '');
+ my $return = eval { __get_result($r, 200, 1); };
+ $self->fatal("POST of '$order->{certificate}' failed - $@", $r) if $@;
+ return $return;
+}
+
+# Revoke given certificate
+# POST to revokeCert endpoint
+# currently only supports revokation with account key
+# $certificate can either be PEM or DER encoded
+# Expects a '200 OK' reply
+sub revoke_certificate {
+ my ($self, $certificate, $reason) = @_;
+
+ my $url = $self->_method('revokeCert');
+
+ if ($certificate =~ /^-----BEGIN CERTIFICATE-----/) {
+ $certificate = PVE::Certificate::pem_to_der($certificate);
+ }
+
+ my $req = {
+ certificate => encode($certificate),
+ reason => $reason // 0,
+ };
+ # TODO: set use_jwk if revoking with certificate key
+ my $r = $self->do(POST => $url, $req);
+ eval {
+ die "unexpected code $r->code\n" if $r->code != 200;
+ };
+ $self->fatal("POST to '$url' failed - $@", $r) if $@;
+}
+
+# Request validation of challenge
+# POST to challenge URL
+# call after validation has been setup
+# returns (potentially updated) challenge object
+sub request_challenge_validation {
+ my ($self, $url, $key_authorization) = @_;
+
+ my $req = { keyAuthorization => $key_authorization };
+
+ my $r = $self->do(POST => $url, $req);
+ my $return = eval { __get_result($r, 200); };
+ $self->fatal("POST to '$url' failed - $@", $r) if $@;
+ return $return;
+}
+
+# actually 'do' a $method request on $url
+# $data: input for JWS, optional
+# $use_jwk: use JWK instead of KID in JWD (see sub jws)
+sub do {
+ my ($self, $method, $url, $data, $use_jwk) = @_;
+
+ $self->fatal("Error: can't $method to empty URL") if !$url || $url eq '';
+
+ my $headers = HTTP::Headers->new();
+ $headers->header('Content-Type' => 'application/jose+json');
+ my $content = defined($data) ? $self->jws($use_jwk, $data, $url) : undef;
+ my $request;
+ if (defined($content)) {
+ $content = tojs($content);
+ $request = HTTP::Request->new($method, $url, $headers, $content);
+ } else {
+ $request = HTTP::Request->new($method, $url, $headers);
+ }
+ my $res = $self->{ua}->request($request);
+ if (!$res->is_success) {
+ # check for nonce rejection
+ if ($res->code == 400 && $res->decoded_content) {
+ my $parsed_content = fromjs($res->decoded_content);
+ if ($parsed_content->{type} eq 'urn:ietf:params:acme:error:badNonce') {
+ warn("bad Nonce, retrying\n");
+ $self->{nonce} = $res->header('Replay-Nonce');
+ return $self->do($method, $url, $data, $use_jwk);
+ }
+ }
+ $self->fatal("Error: $method to $url\n".$res->decoded_content, $res);
+ }
+ if (my $nonce = $res->header('Replay-Nonce')) {
+ $self->{nonce} = $nonce;
+ }
+ return $res;
+}
+
+1;
projects / proxmox-acme.git / commitdiff