diff options
| -rw-r--r-- | Changelog | 2 | ||||
| -rwxr-xr-x | client | 56 | ||||
| -rw-r--r-- | config/lacme-accountd.conf | 6 | ||||
| -rwxr-xr-x | lacme-accountd | 7 | ||||
| -rw-r--r-- | lacme-accountd.1.md | 18 | ||||
| -rw-r--r-- | tests/accountd-kid | 59 |
6 files changed, 130 insertions, 18 deletions
@@ -52,6 +52,8 @@ lacme (0.7.1) upstream; in messages to the standard error. * lacme-accountd(1): new setting 'logfile' to log (decoded) incoming signature requests to a file. + * lacme-accountd(1): new setting 'keyid' to easily revoke all account + management access from the client. + Improve nginx/apache2 snippets for direct serving of challenge files (with the new 'challenge-directory' logic symlinks can be disabled). + Split Nginx and Apapche2 static configuration snippets into seperate @@ -90,7 +90,7 @@ do { print STDERR "WARN: Ignoring extra greeting data from accountd \"$extra\"\n"; } else { print STDERR "Received extra greeting data from accountd: $extra\n" if $ENV{DEBUG}; - ($JWK_thumbprint, $ALG) = @$h{qw/jwk-thumbprint alg/}; + ($JWK_thumbprint, $ALG, $KID) = @$h{qw/jwk-thumbprint alg kid/}; } } my $jwk_str = $S->getline() // die "ERROR: No JWK from lacme-accountd\n"; @@ -194,39 +194,50 @@ sub request_json_decode($;$$) { ############################################################################# -# JSON-encode the hash reference $h and send it to the ACME server $uri -# encapsulated it in a JSON Web Signature (JWS). +# JSON-encode the hash reference $payload and send it to the ACME server +# $url encapsulated it in a JSON Web Signature (JWS). $header MUST +# contain either "jwk" (JSON Web Key) or "kid" per RFC 8555 sec. 6.2 # https://tools.ietf.org/html/rfc8555 # -sub acme($;$) { - my ($uri, $h) = @_; - die "Missing nonce\n" unless defined $NONCE; +sub acme2($$;$) { + my ($url, $header, $payload) = @_; # Produce the JSON Web Signature: RFC 7515 section 5 - my %header = ( alg => $ALG, nonce => $NONCE, url => $uri ); - defined $KID ? ($header{kid} = $KID) : ($header{jwk} = $JWK); - my $payload = defined $h ? encode_base64url(json()->encode($h)) : ""; - my $protected = encode_base64url(json()->encode(\%header)); - my $data = $protected .'.'. $payload; - $S->printflush($data, "\r\n"); + $header->{alg} = $ALG; + $header->{nonce} = $NONCE // die "Missing nonce\n"; + $header->{url} = $url; + my $protected = encode_base64url(json()->encode($header)); + $payload = defined $payload ? encode_base64url(json()->encode($payload)) : ""; + + $S->printflush($protected, ".", $payload, "\r\n"); my $sig = $S->getline() // die "ERROR: No response from lacme-accountd\n"; $sig =~ s/\r\n\z// or die; undef $NONCE; # consume the nonce # Flattened JSON Serialization, RFC 7515 section 7.2.2 - request(POST => $uri, { + request(POST => $url, { payload => $payload, protected => $protected, signature => $sig }); } +# Like above, but always use "kid" +sub acme($;$) { + my ($url, $payload) = @_; + die "Missing KID\n" unless defined $KID; + acme2($url, {kid => $KID}, $payload) +} + my $SERVER_URI = $CONFIG->{server} // '@@acmeapi_server@@'; my %RES; # Get the resource URI from the directory sub acme_resource($%) { my $r = shift; + my %payload = @_; + my %protected; + unless (%RES) { # query the ACME directory to get resources URIs %RES = %{ request_json_decode(request(GET => $SERVER_URI)) }; @@ -235,12 +246,23 @@ sub acme_resource($%) { request(HEAD => $RES{newNonce}); } my $uri = $RES{$r} // die "Unknown resource '$r'\n"; - acme($uri, {@_}); + + if ($r eq "newAccount" or ($r eq "revokeCert" and !defined $KID)) { + # per RFC 8555 sec. 6.2 these requests MUST have a JWK + print STDERR "WARNING: lacme-accountd supplied an empty JWK; try removing 'keyid' ", + "setting from lacme-accountd.conf if the ACME resource request fails.\n" + unless %$JWK; + return acme2($uri, {jwk => $JWK}, \%payload); + } else { + # per RFC 8555 sec. 6.2 all other requests MUST have a KID + return acme($uri, \%payload); + } } # Set the key ID (registration URI) sub set_kid(;$) { my $die = shift // 1; + return if defined $KID; # already set my $r = acme_resource('newAccount', onlyReturnExisting => JSON::true ); if ($r->is_success()) { $KID = $r->header('Location'); @@ -269,6 +291,7 @@ if ($COMMAND eq 'account') { if ($r->is_success()) { $KID = $r->header('Location'); + print STDERR "Key ID: $KID\n"; $r = acme($KID, \%h); request_json_decode($r, 1, \*STDOUT) if $r->is_success() and $r->content_type() eq 'application/json'; @@ -391,7 +414,10 @@ elsif ($COMMAND eq 'revokeCert') { my $der = do { local $/ = undef; <STDIN> }; close STDIN or die "close: $!"; - # send a KID if the request is signed with the acccount key, otherwise send a JWK + # RFC 8555 sec. 6.2: send a KID if the request is signed with the + # acccount key, otherwise send a JWK + # We have no way to know which of the account key or certificate key + # is used, so we try to get a KID and fallback to sending the JWK set_kid(0); my $r = acme_resource('revokeCert', certificate => encode_base64url($der)); diff --git a/config/lacme-accountd.conf b/config/lacme-accountd.conf index f31cf67..d31c6c8 100644 --- a/config/lacme-accountd.conf +++ b/config/lacme-accountd.conf @@ -20,6 +20,12 @@ # #socket = %t/S.lacme +# The "Key ID", as shown by `acme account`, to give the ACME client. +# A non-empty value revokes all account management access (status +# change, contact address updates etc.) from the client. +# +#keyid = + # Be quiet. Possible values: "Yes"/"No". # #quiet = Yes diff --git a/lacme-accountd b/lacme-accountd index d8c96b0..a842bce 100755 --- a/lacme-accountd +++ b/lacme-accountd @@ -125,7 +125,7 @@ do { open $LOG, ">>", $1 or die "Can't open $1: $!"; } error("Invalid section(s): ".join(', ', keys %$h)) if %$h; - my %h = map { $_ => delete $h2->{$_} } qw/privkey gpg socket logfile quiet/; + my %h = map { $_ => delete $h2->{$_} } qw/privkey gpg socket logfile keyid quiet/; error("Unknown option(s): ".join(', ', keys %$h2)) if %$h2; $h{quiet} = lc $h{quiet} eq 'yes' ? 1 : 0 if defined $h{quiet}; $OPTS{$_} //= $h{$_} foreach grep {defined $h{$_}} keys %h; @@ -183,6 +183,11 @@ if ($OPTS{privkey} =~ /\A(file|gpg):(\p{Print}+)\z/) { # use of SHA-256 digest in the thumbprint is hardcoded, see RFC 8555 sec. 8.1 $JWK_STR = JSON::->new->utf8->canonical->encode(\%jwk); $extra_greeting{"jwk-thumbprint"} = encode_base64url(sha256($JWK_STR)); + + if ((my $kid = $OPTS{keyid} // "") ne "") { + $extra_greeting{kid} = $kid; + $JWK_STR = "{}"; + } $EXTRA_GREETING_STR = JSON::->new->encode(\%extra_greeting); } else { diff --git a/lacme-accountd.1.md b/lacme-accountd.1.md index d0b2c6b..4933a78 100644 --- a/lacme-accountd.1.md +++ b/lacme-accountd.1.md @@ -119,14 +119,28 @@ leading `--`) in the configuration file. Valid settings are: [`gpg`(1)] to use, as well as some default options. Default: `gpg --quiet`. +*socket* + +: See `--socket=`. + *logfile* : An optional file where to log to. The value is subject to [%-specifier expansion](#percent-specifiers). -*socket* +*keyid* -: See `--socket=`. +: The "Key ID", as shown by `` `acme account` ``, to give the [ACME] + client. With an empty *keyid* (the default) the client forwards the + JSON Web Key (JWK) to the [ACME] server to retrieve the correct + value. A non-empty value therefore saves a round-trip. + + A non-empty value also causes `lacme-accountd` to send an empty JWK, + thereby revoking all account management access (status change, + contact address updates etc.) from the client: any `` `acme account` `` + command (or any command from [`lacme`(8)] before version 0.8.0) is + bound to be rejected by the [ACME] server. This provides a + safeguard against malicious clients. *quiet* diff --git a/tests/accountd-kid b/tests/accountd-kid new file mode 100644 index 0000000..e1bd63d --- /dev/null +++ b/tests/accountd-kid @@ -0,0 +1,59 @@ +# Hide JWK from ACME client and pass KID instead + +# get the key ID +lacme account 2>"$STDERR" || fail +keyid="$(sed -n "/^Key ID: / {s///p;q}" <"$STDERR")" + +# prepare accountd +adduser --disabled-password \ + --home /home/lacme-account \ + --gecos "lacme account user" \ + --quiet lacme-account + +install -olacme-account -glacme-account -Ddm0700 -- \ + ~lacme-account/.config/lacme ~lacme-account/.local/share/lacme +mv -t ~lacme-account/.config/lacme /etc/lacme/account.key +chown lacme-account: ~lacme-account/.config/lacme/account.key + +cat >~lacme-account/.config/lacme/lacme-accountd.conf <<-EOF + privkey = file:%E/lacme/account.key + logfile = %h/.local/share/lacme/accountd.log + keyid = $keyid +EOF + +SOCKET=~lacme-account/S.lacme +runuser -u lacme-account -- lacme-accountd --socket="$SOCKET" --quiet & PID=$! + +# newAccount resource fails as per RFC 8555 sec. 6.2 it requires a JWK +! lacme --socket="$SOCKET" account 2>"$STDERR" || fail +grepstderr -Fxq "WARNING: lacme-accountd supplied an empty JWK; try removing 'keyid' setting from lacme-accountd.conf if the ACME resource request fails." +grepstderr -Fxq "400 Bad Request (Parse error reading JWS)" +! grep -F ">>> OK signing request: header=" ~lacme-account/.local/share/lacme/accountd.log | \ + grep -vF ">>> OK signing request: header=base64url({\"alg\":\"RS256\",\"jwk\":{}," || exit 1 + +# rotate log and restart accountd +kill $PID +wait + +rm ~lacme-account/.local/share/lacme/accountd.log +runuser -u lacme-account -- lacme-accountd --socket="$SOCKET" --quiet & PID=$! + +# newOrder works fine without JWK +lacme --socket="$SOCKET" newOrder +test /etc/lacme/simpletest.rsa.crt -nt /etc/lacme/simpletest.rsa.key + +# and so does revokeCert (for requests authenticated with the account key) +lacme --socket="$SOCKET" revokeCert /etc/lacme/simpletest.rsa.crt +! lacme --socket="$SOCKET" revokeCert /etc/lacme/simpletest.rsa.crt 2>"$STDERR" || fail +grepstderr -Fxq "Revoking /etc/lacme/simpletest.rsa.crt" +grepstderr -Fxq "400 Bad Request (Certificate already revoked)" +grepstderr -Fxq "Warning: Couldn't revoke /etc/lacme/simpletest.rsa.crt" + +kill $PID +wait + +# make sure all signing requests have a KID +! grep -F ">>> OK signing request: header=" ~lacme-account/.local/share/lacme/accountd.log | \ + grep -vF ">>> OK signing request: header=base64url({\"alg\":\"RS256\",\"kid\":\"$keyid\"," || exit 1 + +# vim: set filetype=sh : |