feature: web.shell lets /shell of the web service open a login shell of web.shell_user over a WebSocket for the Router Manager's Shell page, after the user signs in again.

ADR.md

@@ -152,8 +152,8 @@ Status: Accepted
 
 Context: Users are managed from the command line, by an operator at a terminal, and through
 `/users` of the web service, by the Router Manager. Both must apply the same rules to names,
-passwords and person attributes, and both change the directory and the PKI, whose state is one
+passwords and person attributes, and both change the directory and the PKI, whose CRL numbers and
-file, so two changes must not run at the same time. The web unit is sandboxed with
+CRLs two changes must not write at the same time. The web unit is sandboxed with
 `ProtectSystem=strict`.
 
 Decision: `vpnrouter_users.py` holds the user operations, the checks and a session that takes a
@@ -162,9 +162,9 @@ lock and the connection of the user manager account. The web service imports it
 the output, text for people and JSON with `--json`. The web unit allows writing the paths the
 operations need: `/run/vpn-router` for the lock, its `RuntimeDirectory`, which systemd creates
 before the service starts, also before setup has run, and keeps when it stops, as setup's state
-files are there too; `/etc/vpn-router/pki` for the certificates and the PKI's state, and
+files are there too, and `/etc/swanctl/x509crl`, `/etc/openvpn/server` and
-`/etc/swanctl/x509crl`, `/etc/openvpn/server` and `/var/lib/vpn-router/pki-publish` for the
+`/var/lib/vpn-router/pki-publish` for the copies of the CRLs a revocation signs; the PKI itself is
-CRLs a revocation signs. The PKI module, `vpnrouter_pki.py`, works the same way for `/ca`,
+in the directory (ADR-32). The PKI module, `vpnrouter_pki.py`, works the same way for `/ca`,
 `vpn-router-ca` and `vpn-router-setup`, and its lock is the users' lock, as adding and removing
 a user issue and revoke a certificate.
 
@@ -757,8 +757,8 @@ of common name and the subject alternative names a certificate may have; `vpn-se
 `vpn-user` are issued by the router only, so no certificate for another use comes from the P2S
 CA. The module `vpnrouter_pki.py`, with `python3-cryptography` from the Ubuntu archive, builds
 the keys, certificates, CSRs and CRLs in the processes that need them, as the user module does
-(ADR-6); the settings are the `pki` section of `vpn-router.json` and the state is
+(ADR-6); the settings are the `pki` section of `vpn-router.json`, and the CAs and the
-`pki/state.json`. Keeping the root key off the router is recommended, not required: while it is
+certificates are kept in the router's directory (ADR-32). Keeping the root key off the router is recommended, not required: while it is
 on the router a new issuing CA is signed at once, and while it is not the CA gets its key and a
 CSR, signed offline and imported with `vpn-router-ca` or `/ca`. The root key itself crosses
 neither the API nor the Manager. For a certificate of something other than the router, the router
@@ -808,14 +808,17 @@ secret to distribute. Azure's VPN gateway authenticates site-to-site connections
 keys only.
 
 Decision: A connection's `auth` is `psk`, the default, or `certificate`. With `certificate` the
-router presents one site-to-site certificate of its `s2s` CA, whose names are `wan.local_fqdn`,
+router presents one site-to-site certificate of its `s2s` CA, whose names are `wan.local_fqdn` and
-the public address and the internal address, so it fits every `local_id_mode`; the peer's
+the local identities the connections with `certificate` use, the public or the internal address of
+their `local_id_mode`, and no address no connection presents, such as an internal address the peers
+never see; the peer's
 certificate must name the connection's `id` and be issued by the router's `s2s` CA or, when the
 connection has `remote_ca`, by that CA, its PEM certificate kept in the connection and copied to
 `/etc/swanctl/x509ca/s2s-<name>.pem`. A peer without a PKI gets its certificate from the router.
 
 Consequences: The connection Azure's gateway needs stays `psk`, so the platform writes nothing
-new. The router's site-to-site certificate is issued again when an address it names changes. The
+new. The router's site-to-site certificate is issued again when the set of names it needs changes,
+such as when a connection's `local_id_mode` or its address changes. The
 router does not check a remote CA's revocations unless strongSwan can fetch the CRL its
 certificates name.
 
@@ -861,3 +864,60 @@ Manager shows which one is in effect.
 Consequences: The first setup run with HTTPS starts the installation and serves HTTPS on the run
 that follows it. The key of Caddy's repository is trusted as downloaded over HTTPS, the way Caddy's
 installation instructions do it. Going back to the archive's Caddy is a manual downgrade.
+
+## ADR-32: The PKI is kept in the router's directory
+
+Status: Accepted
+
+Context: The CAs, their keys and CRLs, the inventory of the certificates issued and their
+revocations, and the router's and the users' certificates and keys need a store. Files with a
+JSON state file cannot be searched, and are copied apart from the users the certificates belong
+to. The router runs slapd, which holds the users and is provisioned on every
+configured router (ADR-10), and PostgreSQL, which holds the refresh tokens and the metrics, may
+be another server (`web.database`) and is in a backup only with `backup.metrics`. RFC 4523
+defines `pkiCA` with `cACertificate` and `certificateRevocationList`, and `userCertificate`, which
+OpenLDAP's core schema includes.
+
+Decision: The PKI is held in `ou=pki` of the router's directory. A CA is an entry of the package's
+class `vpnRouterAuthority` with `cACertificate` and `certificateRevocationList`, its key, its CSR,
+its CRL number, the source of the root CRL and the time it was retired; a certificate is an entry
+of `vpnRouterCertificate` named by its serial number under its CA, with `userCertificate`, its
+kind, template, names, expiry and revocation, and the key of a router or user certificate. A
+user's certificate is also the `userCertificate` of the user's entry. An ACL lets no account read
+`vpnRouterPrivateKey`; only root, the database's root DN, does, through the local socket. A
+retired CA keeps its entry, renamed, so its certificates stay in the inventory. A root supplied
+from outside, by cloud-init or by hand, is placed as files before the first setup with a platform,
+which imports and removes them. strongSwan, OpenVPN, Caddy and the system's trust store read files,
+so setup and every revocation write them from the directory. Setup provisions the directory before
+the PKI; without the directory it leaves the PKI and its files as they are and configures the rest.
+
+Consequences: `slapcat` writes the users and the PKI into every backup in one consistent copy, and a
+restore brings both back together. The PKI depends on slapd, as the users already do, and not on
+PostgreSQL. The directory holds the CA keys, so it is as sensitive as the CA itself. The schema
+grows by the package's PKI attributes and classes, which setup adds to slapd's configuration.
+
+## ADR-33: The web service opens a shell for the Router Manager over a WebSocket
+
+Context: The Router Manager's Shell page gives an administrator a terminal on the router in the
+browser, with xterm.js, the terminal of VS Code. A terminal needs a full-duplex channel, which
+xterm.js expects as a WebSocket. The web service runs in a sandbox (`NoNewPrivileges`,
+`ProtectSystem=strict`, `ProtectHome`) that a shell must not inherit, and as root, which a shell
+in a browser should not be. A stolen session cookie or access token alone must not give a shell.
+
+Decision: `/shell` of the web service is off until `web.shell` is set on the router; the Router
+Manager cannot set it. The shell runs as `web.shell_user`, a system user other than root, which
+reaches root through its sudoers entry. `POST /shell` signs the user in again with the password
+and TOTP code and gives a one-time ticket valid 30 seconds; a WebSocket on `GET /shell` with that
+ticket gets the shell. The WebSocket of RFC 6455 is implemented on the standard library inside the
+web service's `http.server`, server side only, without extensions. `systemd-run --pty` starts the
+shell in a transient unit with a PAM login session, outside the sandbox, and `setsid --ctty`
+makes the terminal its controlling terminal so window sizes reach the shell. A shell idle for
+`web.shell_idle_minutes` is closed, and the journal records every opening and end. The Router
+Manager checks the session and the WebSocket's origin, and relays the bytes to the router after
+both handshakes.
+
+Consequences: Who can sign in as a member of `admins` and knows the password and the current code
+can get a shell when the router allows one; a session alone cannot. The ticket travels in the URL
+and appears in request logs, used up. The shell's sessions show up as `vpn-router-shell-<id>`
+units and logind sessions of `web.shell_user`. The shell's traffic is as protected as the Router
+Manager's: HTTPS to Caddy, plain HTTP on the internal network to the web service.

README.md

@@ -128,6 +128,9 @@ must have the type shown below; an unknown section or setting is an error.
 | `web` | `database` | string | | A PostgreSQL connection string for the refresh tokens; without it, the `vpn-router` database on this host that the web service creates |
 | `web` | `trusted_proxies` | list | the address the call came in on | Addresses whose `X-Forwarded-For` header names the client for the `/auth` rate limit and the Client IP of the status |
 | `web` | `status_content` | string | `basic` | What `/` and `/status` show: `basic`, `standard` or `full` (see Status web service) |
+| `web` | `shell` | boolean | `false` | `/shell` opens a login shell of `shell_user` for a member of `admins` (see The shell) |
+| `web` | `shell_user` | string | | The system user the shell runs as, not `root`; required by `shell` |
+| `web` | `shell_idle_minutes` | integer | `15` | Minutes without a keystroke after which a shell is closed, 1 to 1440 |
 | `https` | `enabled` | boolean | `true` | Caddy serves the status web service and the Router Manager over HTTPS for `wan.local_fqdn` |
 | `https` | `email` | string | | The e-mail address of the Let's Encrypt account |
 | `https` | `web_port` | integer | `7444` | HTTPS port of the status web service |
@@ -144,6 +147,7 @@ must have the type shown below; an unknown section or setting is an error.
 | `pki` | `s2s_name` | string | `VPN Router Site-to-Site CA` | Common name of the site-to-site issuing CA |
 | `pki` | `issuing_cas` | object | | The general-purpose issuing CAs, each a name and `{name, templates, acme}` (see Certificates) |
 | `pki` | `templates` | object | | Certificate templates, each a name and the options it changes or defines (see Certificates) |
+| `pki` | `extended_key_usages` | object | | Custom extended key usages templates may give, each a name and its OID in dotted form (see Certificates) |
 | `pki` | `root_key_warning` | boolean | `true` | `vpn-router-ca status` and `/ca` warn while the root key is on the router; `false` silences that warning |
 | `metrics` | `enabled` | boolean | `true` | The metrics service: collection, history and `/metrics` |
 | `metrics` | `listen` | string | `internal` | The interfaces `/metrics` is served on: `internal`, `external` or `both` |
@@ -202,8 +206,9 @@ certificate; all such connections are written to `/etc/swanctl/conf.d/site-to-si
 Traffic from a connection's `local_cidrs` to its `cidrs` is not masqueraded.
 
 With `auth` `certificate`, the router authenticates with its site-to-site certificate, which the
-site-to-site issuing CA signs for `wan.local_fqdn`, the public address and the internal
+site-to-site issuing CA signs for `wan.local_fqdn` and for the public or the internal address
-address, so it fits every `local_id_mode`. The peer's certificate must name `id` and be issued
+that a connection with `auth` `certificate` uses as its identity (`local_id_mode` `public_ip` or
+`internal_ip`); it is issued again when that set of names changes. The peer's certificate must name `id` and be issued
 by the router's site-to-site CA, or by the CA of `remote_ca`. A peer with no PKI of its own gets
 its certificate from the router (template `site-to-site`, see Certificates), with the root and
 the site-to-site CA certificates as its trust anchors.
@@ -371,18 +376,27 @@ services - that is what `systemctl restart vpn-router-setup` adds.
 
 ## Certificates
 
-The router has a two-level certificate authority in `/etc/vpn-router/pki` (mode 0700), kept by
+The router has a two-level certificate authority, kept by `vpn-router-setup` and managed with
-`vpn-router-setup` and managed with `vpn-router-ca`, `vpn-router-user` and `/ca` of the status
+`vpn-router-ca`, `vpn-router-user` and `/ca` of the status web service, which the Router Manager
-web service, which the Router Manager uses:
+uses. It is held in `ou=pki,dc=vpn-router,dc=local` of the router's directory, next to the users:
 
 ```
-root/cert.pem  root/key.pem  root/crl.pem       the root CA; key.pem is absent while the root is offline
+cn=root                       the root CA; without vpnRouterPrivateKey while the root is offline
-ca/<name>/cert.pem  key.pem  crl.pem  csr.pem    an issuing CA; csr.pem while it waits for the offline root
+cn=<name>                     an issuing CA; with vpnRouterCertificateRequest while it waits for the offline root
-router/vpn-server_cert.pem  _key.pem              the router's VPN server certificate
+cn=<name>-<time>              an issuing CA taken out of use, with vpnRouterRetired
-router/site-to-site_cert.pem  _key.pem            the router's site-to-site certificate
+serialNumber=<serial>,cn=<CA> a certificate the CA issued
-users/<user>_cert.pem  _key.pem                   the users' certificates
+```
-retired/<name>-<time>/                            the issuing CAs taken out of use
+
-state.json                                        the certificates issued, revocations and CRL numbers
+A CA entry (class `vpnRouterAuthority`) has its certificate (`cACertificate;binary`), key, CRL
+(`certificateRevocationList;binary`) and CRL number. A certificate entry (class
+`vpnRouterCertificate`) has the certificate (`userCertificate;binary`), its kind (`ca`, `router`,
+`user` or `external`), template, names, expiry and revocation, and for the router's and the users'
+certificates the key. A user's certificate is also the `userCertificate` of the user's entry. No
+account of the directory reads a key (`vpnRouterPrivateKey`); only root does, through the local
+socket. `slapcat` writes the whole PKI into every backup with the users.
+
+```sh
+ldapsearch -Q -Y EXTERNAL -H ldapi:/// -b ou=pki,dc=vpn-router,dc=local -s one cn
 ```
 
 ### The CAs
@@ -403,8 +417,8 @@ The root signs the issuing CAs only (path length 1), and the issuing CAs sign th
 Once a platform is chosen, `vpn-router-setup` creates what is missing: the root when it has
 neither certificate nor key, each issuing CA, the router's certificates once `wan.local_fqdn` is
 set, and the CRLs. The names, lifetimes and key type of `pki` apply when something is created. An
-issuing CA removed from `pki.issuing_cas` is retired: its directory moves to `retired/` and its
+issuing CA removed from `pki.issuing_cas` is retired: its entry is renamed `cn=<name>-<time>`,
-certificate is revoked on the root CRL. The router renews its own certificates when less than a
+loses its key, and its certificate is revoked on the root CRL. The router renews its own certificates when less than a
 third of their lifetime is left, when the names they need change, or when their CA changes; a
 user's certificate is renewed by removing and adding the user.
 
@@ -432,7 +446,8 @@ A template says what a certificate holds:
 | `key` | string | `rsa-3072` | `rsa-2048`, `rsa-3072`, `rsa-4096`, `ec-p256` or `ec-p384`, for a key the router makes |
 | `days` | integer | `365` | Days the certificate is valid, at most until its CA's certificate expires |
 | `key_usage` | list | `digital_signature` | Of `digital_signature`, `content_commitment`, `key_encipherment`, `data_encipherment`, `key_agreement` |
-| `extended_key_usage` | list | | Of `server_auth`, `client_auth`, `code_signing`, `email_protection`, `time_stamping`, `ocsp_signing`, `ipsec_ike`, `ike_intermediate` |
+| `extended_key_usage` | list | | Of the built-in `server_auth`, `client_auth`, `code_signing`, `email_protection`, `time_stamping`, `ocsp_signing`, `ipsec_ike`, `ike_intermediate`, and the custom usages of `pki.extended_key_usages` |
+| `policies` | list | | Certificate policy OIDs in dotted form, written into a Certificate Policies extension |
 | `subject` | string | `name` | The common name: `dns`, a DNS name, which is also a subject alternative name; `name`, any name; `email`, an e-mail address |
 | `sans` | list | | The subject alternative names allowed: of `dns`, `ip`, `email` |
 
@@ -451,15 +466,25 @@ templates of its own, named like the issuing CAs:
 
 ```json
 "pki": {
-  "issuing_cas": { "servers": { "name": "Example Server CA", "templates": ["server", "web"] } },
+  "issuing_cas": { "servers": { "name": "Example Server CA", "templates": ["server", "web", "smartcard"] } },
+  "extended_key_usages": { "smartcard_logon": "1.3.6.1.4.1.311.20.2.2" },
   "templates": {
     "server": { "days": 397 },
     "web": { "key": "ec-p256", "days": 90, "key_usage": ["digital_signature"],
-             "extended_key_usage": ["server_auth"], "subject": "dns", "sans": ["dns"] }
+             "extended_key_usage": ["server_auth"], "subject": "dns", "sans": ["dns"] },
+    "smartcard": { "key_usage": ["digital_signature", "key_encipherment"],
+                   "extended_key_usage": ["client_auth", "smartcard_logon"], "subject": "name",
+                   "sans": ["email"], "policies": ["1.3.6.1.4.1.99999.1.1"] }
   }
 }
 ```
 
+A custom extended key usage is first added to `pki.extended_key_usages`, a name of at most 31
+lowercase letters, digits, hyphens and underscores that is not a built-in one, and its OID; a
+template then gives it by its name. A usage a template gives cannot be removed. `policies` puts
+the OIDs of the issuance policies a certificate is issued under into its Certificate Policies
+extension, without qualifiers.
+
 ### Issuing and revoking
 
 ```sh
@@ -541,9 +566,9 @@ vpn-router-ca root import-crl root.crl
 ```
 
 An existing root CA of your own is used by placing its certificate, and its key if the router may
-use it, before choosing the platform: `vpn-router-ca root import-cert root-cert.pem`, or the files
+use it, as `/etc/vpn-router/pki/root/cert.pem` and `key.pem` before `vpn-router-setup` first runs
-`root/cert.pem` and `root/key.pem`. Without the key, the issuing CAs wait for their certificates
+with a platform, as cloud-init can. Setup imports them into the directory and removes the files.
-as above.
+Without the key, the issuing CAs wait for their certificates as above.
 
 ### ACME server
 
@@ -623,7 +648,7 @@ it is added:
 
 - a VPN user, an `inetOrgPerson` with a first name, a last name and an e-mail address
   (`givenName`, `sn` and `mail`; `cn` is the first and the last name), and a client certificate
-  with the user name as its common name, in `/etc/vpn-router/pki/users`;
+  with the user name as its common name, the entry's `userCertificate`, whose key the PKI keeps;
 - a Manager-only account, an `account`, `simpleSecurityObject` and `vpnRouterAccount` with the
   name, the password and an optional e-mail address, for notifications: no names and no
   certificate, so no VPN access. It can sign in to `/auth` and, as a member of `admins`, manage
@@ -782,7 +807,7 @@ configuration: no key, identity, subnet, or address but the client's. They show
 |---|---|
 | `basic` (default) | The overall status (`ok` or `degraded`), the time and the Client IP |
 | `standard` | Also the `vpn-router` version, the `vpn-router-manager` version or that it is not installed, and the number of active services and of services in any other state, without their names |
-| `full` | Also each service and its state, Docker, and the state of each site-to-site connection, road-warrior, OpenVPN and WireGuard |
+| `full` | Also each service and its state, Docker, how many site-to-site connections are set up and how many of them are established (`site_to_site`: `connections` and `established`, `null` when swanctl cannot be asked), road-warrior, OpenVPN and WireGuard |
 
 The Client IP is the address the request came from: the last entry of `X-Forwarded-For` for a
 request from one of `web.trusted_proxies`, by default the address the request came in on, so
@@ -830,8 +855,9 @@ road-warrior access is configured, of `wg-quick@wg0` when WireGuard is, and of
 OpenVPN clients, from the server's status file, which OpenVPN rewrites every minute; the package version and,
 as `manager_version`, the installed version of `vpn-router-manager` (`null`, shown as not installed, without it); whether
 Docker is installed, and when it is, the state of `docker.service` and of `vpn-router-docker`
-(the Docker rules), which do not change `status`; as `site_to_site.connections`, whether each
+(the Docker rules), which do not change `status`; as `site_to_site`, the number of site-to-site
-site-to-site connection that is set up is established (`null` when swanctl cannot be asked); the number of connected road-warrior (IPsec P2S) clients; and
+connections that are set up (`connections`) and of those established (`established`, `null` when
+swanctl cannot be asked), without their names; the number of connected road-warrior (IPsec P2S) clients; and
 the WireGuard peers with the age of their last handshake and their traffic. `status` is `ok` when
 all these services are active, and `degraded` otherwise.
 
@@ -842,7 +868,7 @@ curl http://10.0.0.4:7081/status
 
 ### Tokens and signing in
 
-`/config`, `/users`, `/service-accounts`, `/groups`, `/site-to-site` and `/account` need a JWT in an `Authorization: Bearer` header, signed with
+`/config`, `/users`, `/service-accounts`, `/groups`, `/site-to-site`, `/shell` and `/account` need a JWT in an `Authorization: Bearer` header, signed with
 HS256 by the key the web service makes on its first run, `/etc/vpn-router/web.key` (root only).
 The key never leaves the router; while it does not exist these paths and `/auth` are not served
 (404). A missing, expired or wrongly signed token, or one of another algorithm, gets 401 with
@@ -894,6 +920,39 @@ curl -H 'Content-Type: application/json' -d '{"name": "alice", "password": "s3cr
 curl -H "Authorization: Bearer $TOKEN" http://10.0.0.4:7081/config
 ```
 
+### The /status/full page
+
+`/status/full`, with the same token as `/config`, shows the whole status document, as `/status`
+does with `web.status_content` `full`, whatever that setting says, so the Router Manager shows
+every service and tunnel while the public status page shows less.
+
+### The shell
+
+While `web.shell` is `true`, `/shell` gives a member of `admins` a login shell on the router, as
+the system user `web.shell_user`, for the Router Manager's Shell page. It is off by default and
+switched on and off on the router only:
+
+```sh
+vpn-config-edit set web.shell_user azureuser
+vpn-config-edit set web.shell true
+```
+
+| Request | Body | Answer |
+| --- | --- | --- |
+| `POST /shell` | `{"password", "code"}`; `code` only for a user enrolled for TOTP | `{"ticket", "expires_in": 30}` |
+| `GET /shell?ticket=<ticket>` | a WebSocket handshake | the terminal |
+
+`POST /shell` needs an access token of `/auth`, not one of `vpn-router-token`, and signs its user
+in again: a wrong password or code gets 403 and counts as a failed login. The ticket opens one
+shell for the same user within 30 seconds. Over the WebSocket, binary messages of the client
+are keystrokes, a text message `{"cols", "rows"}` sets the window size, and binary messages of
+the router are the terminal's output. The shell is a PAM login session of `web.shell_user`, run
+by `systemd-run` in a transient unit `vpn-router-shell-<id>`; sudo works as the user's sudoers
+entry allows. It is closed after `web.shell_idle_minutes` without a keystroke, when the shell
+exits, or when the connection closes; the router then sends a close frame with the reason. The
+journal of `vpn-router-web` records who opened each shell, from which address, in which unit,
+when it ended and why.
+
 ### The /config page
 
 `/config` shows what `/` and `/status` leave out, for a client such as manage-ui:
@@ -1056,11 +1115,12 @@ A change is made, checked and applied as for `/site-to-site`.
 
 | Request | Body | Answer |
 | --- | --- | --- |
-| `GET /ca` | | `{"settings", "templates", "status", "certificates"}` |
+| `GET /ca` | | `{"settings", "templates", "extended_key_usages", "status", "certificates"}` |
 | `PUT /ca` | any of the settings of the `pki` section | `{"settings", "templates"}` |
 | `POST /ca/certificates` | `{"ca", "template", "csr"}` | 201 and `{"serial", "certificate", "chain"}`, PEM |
 | `POST /ca/certificates` | `{"ca", "template", "subject", "sans", "password"}` | 201 and `{"serial", "pfx"}`, a PKCS#12 file in base64 |
 | `POST /ca/certificates/<serial>/revoke` | `{"reason"}`, optional | the certificate, with `reissue` for a router certificate |
+| `GET /ca/bundle/<name>` | | `{"name", "pem"}`: the certificates a client trusts the CA with, the root alone for `root`, the issuing CA followed by the root for an issuing CA |
 | `GET /ca/issuing/<name>/csr` | | `{"name", "csr", "extensions"}` of an issuing CA waiting for the offline root |
 | `PUT /ca/issuing/<name>/certificate` | `{"certificate"}`, PEM, signed by the root | `{"name", "subject", "expires"}` |
 | `PUT /ca/root/crl` | `{"crl"}`, PEM, signed by the root | `{"next_update"}` |
@@ -1069,6 +1129,7 @@ The answer of `GET /ca` holds:
 
 - **`settings`:** the `pki` section.
 - **`templates`:** every template, the built-in ones included, with all its options.
+- **`extended_key_usages`:** every extended key usage templates may give, name -> `{"oid", "builtin"}`.
 - **`status`:** `root` (`subject`, `expires`, `key`, whether the root key is on the router, `crl_next_update` and `crl_source`, `signed` or `uploaded`), `authorities`, one per issuing CA (`name`, `common_name`, `state`: `active`, `pending` or `missing`, `builtin`, `templates`, `acme`, `subject`, `expires`, `key`, `crl_next_update`, `acme_url`), `retired` and `warnings`.
 - **`certificates`:** the certificates issued, newest first, each `{"serial", "ca", "kind", "template", "subject", "sans", "created", "expires", "revoked", "reason", "state"}`; `kind` is `ca`, `router`, `user` or `external`, and `state` `valid`, `expired` or `revoked`.
 
@@ -1266,12 +1327,12 @@ A backup holds the state that `vpn-router-setup` cannot make again:
 
 | Item | Content |
 |---|---|
-| `/etc/vpn-router` | `vpn-router.json`, the secrets, `rclone.conf`, and the PKI: the CAs, the root key while it is on the router, and the certificates of the router and the users |
+| `/etc/vpn-router` | `vpn-router.json`, the secrets and `rclone.conf` |
 | `/etc/wireguard` | The WireGuard keys and the peers |
 | `/etc/ufw`, `/etc/default/ufw` | The firewall rules |
 | `/etc/vpn-router-manager` | The Router Manager's settings, when it is installed |
 | `files/<path>` | Each `psk_file` outside `/etc/vpn-router` |
-| `ldap/vpn-router.ldif` | The user directory, written by `slapcat`: users, groups, service accounts, password hashes and TOTP secrets |
+| `ldap/vpn-router.ldif` | The user directory, written by `slapcat`: users, groups, service accounts, password hashes and TOTP secrets, and the PKI: the CAs and their keys, the root key while it is on the router, and the certificates issued, with the keys of the router's and the users' certificates |
 | `postgresql/vpn-router.dump` | With `backup.metrics`, the database of the metrics and the refresh tokens, written by `pg_dump -Fc` |
 | `manifest.json` | The host, the time, the version of the package, the schedule and the items |
 
@@ -1373,8 +1434,8 @@ file when the package created them, and Caddy's configuration `/etc/caddy/vpn-ro
 `/var/lib/caddy` belongs to the `caddy` package. It removes the backup timer's schedule, the
 record of the last backup, the published CA files, the copies of the ACME CAs in
 `/etc/caddy/vpn-router-pki` and OpenVPN's CA and CRL files. Caddy stays installed, and with it the
-source of Caddy's repository. Key material, users and backups are never deleted: `/etc/vpn-router/pki`,
+source of Caddy's repository. Key material, users and backups are never deleted:
-`/etc/vpn-router/ldap`, `/etc/vpn-router/rclone.conf`, the user directory in slapd, the WireGuard
+`/etc/vpn-router/ldap`, `/etc/vpn-router/rclone.conf`, the user directory in slapd with the PKI, the WireGuard
 key pair, everything under `/etc/swanctl`, the archives in `backup.path` and
 `/var/lib/vpn-router/backup/before-restore` are left alone.
 

debian-package/debian/changelog

@@ -1,3 +1,81 @@
+vpn-router (0.23.0-1) unstable; urgency=medium
+
+  feature: web.shell lets /shell of the web service open a login shell of web.shell_user over a WebSocket for the Router Manager's Shell page, after the user signs in again.
+
+  * web.shell (false), web.shell_user and web.shell_idle_minutes (15).
+  * POST /shell takes the password and the TOTP code and answers a
+    one-time ticket; GET /shell with it is a WebSocket carrying the
+    terminal, closed after web.shell_idle_minutes without a keystroke.
+  * The journal of vpn-router-web records each shell opened and ended.
+
+ -- Slawomir Koszewski <slawek@koszewscy.waw.pl>  Mon, 02 Nov 2026 20:00:00 +0100
+
+vpn-router (0.22.1-1) unstable; urgency=medium
+
+  fix: the status gives the number of site-to-site connections set up and established, not each connection by name.
+
+  * site_to_site of the status document is {"connections", "established"},
+    and the status page shows "Site to site: N of M established".
+
+ -- Slawomir Koszewski <slawek@koszewscy.waw.pl>  Mon, 02 Nov 2026 18:00:00 +0100
+
+vpn-router (0.22.0-1) unstable; urgency=medium
+
+  feature: pki.extended_key_usages adds custom extended key usages by their OIDs, which templates give by name, and a template's policies put certificate policy OIDs into its certificates.
+
+  * pki.extended_key_usages maps a name to the OID of a custom extended
+    key usage; a template's extended_key_usage takes the built-in and the
+    custom names.
+  * The template option policies lists certificate policy OIDs, written
+    into a Certificate Policies extension.
+  * GET /ca answers extended_key_usages, each usage with its OID and
+    whether it is built in.
+
+ -- Slawomir Koszewski <slawek@koszewscy.waw.pl>  Mon, 02 Nov 2026 14:00:00 +0100
+
+vpn-router (0.21.5-1) unstable; urgency=medium
+
+  fix: /status/full of the status web service gives an authenticated client the whole status, whatever web.status_content says.
+
+  * /status/full takes the token of /config and answers the status
+    document as web.status_content full shows it.
+
+ -- Slawomir Koszewski <slawek@koszewscy.waw.pl>  Mon, 02 Nov 2026 12:00:00 +0100
+
+vpn-router (0.21.4-1) unstable; urgency=medium
+
+  fix: vpn-router-setup, vpn-router-ca and /ca read a CA's key and CRL from the directory each as itself, instead of failing on a CA with a CRL.
+
+  * A CA's CRL was read as its key and its key as its CRL, so every
+    operation on a CA with a CRL failed with "Could not deserialize key
+    data".
+
+ -- Slawomir Koszewski <slawek@koszewscy.waw.pl>  Mon, 02 Nov 2026 10:00:00 +0100
+
+vpn-router (0.21.3-1) unstable; urgency=medium
+
+  fix: the PKI is kept in ou=pki of the router's directory instead of files under /etc/vpn-router/pki, and the router's site-to-site certificate names only the identities its connections present, and /ca/bundle gives the certificate bundle of a CA.
+
+  * The CAs with their certificates, keys, CSRs and CRLs, and every
+    certificate issued with its revocation, are entries of the
+    package's schema in ou=pki; a user's certificate is also the
+    userCertificate of the user's entry, and only root reads a key.
+  * slapcat puts the PKI into every backup with the users.
+  * A root CA supplied as /etc/vpn-router/pki/root/cert.pem and key.pem
+    before the first setup is imported into the directory, and the files
+    are removed; vpn-router-ca root import-cert is gone.
+  * Setup provisions the directory before the configuration; without it,
+    the PKI and its files are left as they are.
+  * The router's site-to-site certificate names wan.local_fqdn and the
+    public or internal address a connection with auth certificate uses
+    as its identity, not every address of the router, and is issued
+    again when those names change.
+  * GET /ca/bundle/<name> of the status web service answers the PEM
+    certificates a client trusts a CA with: the root alone, or an issuing
+    CA followed by the root.
+
+ -- Slawomir Koszewski <slawek@koszewscy.waw.pl>  Sun, 01 Nov 2026 10:00:00 +0100
+
 vpn-router (0.21.2-1) unstable; urgency=medium
 
   fix: pki.root_key_warning silences the warning of vpn-router-ca status and /ca about the root key on the router.

debian-package/src/usr/lib/vpn-router/setup

@@ -577,7 +577,12 @@ def manage_caddy(cfg, ctx):
         group = grp.getgrnam(CADDY_GROUP).gr_gid
     except KeyError:
         fail(f'the group {CADDY_GROUP} does not exist; is the caddy package installed?')
-    acme = [name for name in ctx['pki_acme'] if vpnrouter_pki.ready(name)]
+    try:
+        credentials = {name: vpnrouter_pki.authority_files(name) for name in ctx['pki_acme']}
+    except ldap.LDAPError as exc:
+        warn(f'the ACME servers are left out: the PKI cannot be read: {exc}')
+        credentials = {}
+    acme = [name for name, files in credentials.items() if files is not None]
     copied = False
     for folder in (CADDY_PKI_DIR.iterdir() if CADDY_PKI_DIR.is_dir() else []):
         if folder.name not in acme:
@@ -587,8 +592,8 @@ def manage_caddy(cfg, ctx):
         for path in (CADDY_PKI_DIR, folder):
             path.mkdir(mode=0o750, exist_ok=True)
             os.chown(path, 0, group)
-        for file in ('cert.pem', 'key.pem'):
+        for file, data in zip(('cert.pem', 'key.pem'), credentials[name]):
-            copied |= vpnrouter.install_file(vpnrouter_pki.CA_DIR / name / file, folder / file, 0o640)
+            copied |= vpnrouter_pki.write(folder / file, data, 0o640)
             os.chown(folder / file, 0, group)
     authorities = vpnrouter.issuing_cas(cfg)
     caddy_ctx = dict(ctx, manager_port=manager_port() if MANAGER.exists() else 0,
@@ -739,14 +744,19 @@ def main():
     start_bootstrap()
     progress('running', 'configuration')
     cfg = vpnrouter.load_config()
-    ctx, changed = vpnrouter.configure(cfg)
+    if vpnrouter.deferred(cfg):
-
-    if ctx is None:
         print('vpn-router: platform is none, configuration deferred; '
               f'set general.platform in {vpnrouter.CONFIG_FILE}')
         progress('deferred', 'configuration', f'general.platform is none; set it in {vpnrouter.CONFIG_FILE}')
         return 0
 
+    # The directory holds the PKI, which the configuration needs; its problem ends setup only after every other step.
+    failed_step = 'user directory'
+    progress('running', failed_step)
+    problem = manage_directory()
+    progress('running', 'configuration')
+    ctx, changed = vpnrouter.configure(cfg)
+
     progress('running', 'routes')
     if vpnrouter.routing_ready(ctx):
         apply_routes(ctx)
@@ -778,10 +788,6 @@ def main():
     progress('running', 'WireGuard')
     manage_wireguard(ctx, changed)
 
-    # The tunnels are up before the directory and the admin, whose problem ends setup only after every other step.
-    failed_step = 'user directory'
-    progress('running', failed_step)
-    problem = manage_directory()
     if not problem:
         failed_step = 'Router Manager admin'
         progress('running', failed_step)

debian-package/src/usr/lib/vpn-router/vpnrouter.py

@@ -17,6 +17,7 @@ import tempfile
 import urllib.parse
 
 import jinja2
+import ldap
 
 LIB_DIR = pathlib.Path(__file__).resolve().parent
 if str(LIB_DIR) not in sys.path:
@@ -51,12 +52,12 @@ SCHEMA = {
     'openvpn':    {'enabled': False, 'address_pool': '', 'port': 1194, 'protocol': 'udp'},
     'docker':     {'mode': 'auto', 'exposed_ports': []},
     'web':        {'enabled': True, 'listen': DEFAULT_LISTEN, 'port': 7081, 'database': '', 'trusted_proxies': [],
-                   'status_content': 'basic'},
+                   'status_content': 'basic', 'shell': False, 'shell_user': '', 'shell_idle_minutes': 15},
     'https':      {'enabled': True, 'email': '', 'web_port': 7444, 'manager_port': 7443, 'caddy_source': 'ubuntu'},
     'pki':        {'root_name': 'VPN Router Root CA', 'root_days': 7300, 'ca_days': 3650, 'key': 'rsa-4096',
                    'crl_days': 7, 'root_crl_days': 180, 'publish': ['http'], 'p2s_name': 'VPN Router P2S CA',
                    's2s_name': 'VPN Router Site-to-Site CA', 'issuing_cas': {}, 'templates': {},
-                   'root_key_warning': True},
+                   'extended_key_usages': {}, 'root_key_warning': True},
     'metrics':    {'enabled': True, 'listen': 'internal', 'port': 9464, 'https_port': 9465, 'service_account': 'metrics',
                    'otlp_endpoint': '', 'otlp_username': '', 'otlp_password': '',
                    'keep_details': '24 hours', 'keep_hourly': '1 month', 'keep_daily': '3 months',
@@ -135,9 +136,23 @@ PKI_PUBLISH = ('http', 'http-80', 'https', 'https-default')
 #: The key usages a template may give, as the arguments of cryptography's KeyUsage.
 KEY_USAGES = ('digital_signature', 'content_commitment', 'key_encipherment', 'data_encipherment', 'key_agreement')
 
-#: The extended key usages a template may give.
+#: The built-in extended key usages a template may give, name -> OID; pki.extended_key_usages adds custom ones.
-EXTENDED_KEY_USAGES = ('server_auth', 'client_auth', 'code_signing', 'email_protection', 'time_stamping',
+EXTENDED_KEY_USAGES = {
-                       'ocsp_signing', 'ipsec_ike', 'ike_intermediate')
+    'server_auth': '1.3.6.1.5.5.7.3.1',
+    'client_auth': '1.3.6.1.5.5.7.3.2',
+    'code_signing': '1.3.6.1.5.5.7.3.3',
+    'email_protection': '1.3.6.1.5.5.7.3.4',
+    'time_stamping': '1.3.6.1.5.5.7.3.8',
+    'ocsp_signing': '1.3.6.1.5.5.7.3.9',
+    'ipsec_ike': '1.3.6.1.5.5.7.3.17',
+    'ike_intermediate': '1.3.6.1.5.5.8.2.2',
+}
+
+#: The name of a custom extended key usage of pki.extended_key_usages.
+EKU_NAME = re.compile(r'^[a-z][a-z0-9_-]{0,30}$')
+
+#: An object identifier in dotted form, of a custom extended key usage or a certificate policy.
+OID = re.compile(r'^[0-2](\.(0|[1-9][0-9]*)){1,63}$')
 
 #: What the common name of a template's certificates is: a DNS name, any name, or an e-mail address.
 TEMPLATE_SUBJECTS = ('dns', 'name', 'email')
@@ -147,7 +162,7 @@ SAN_TYPES = ('dns', 'ip', 'email')
 
 #: A certificate template: option -> default, the type of the default being the required type.
 TEMPLATE = {'key': 'rsa-3072', 'days': 365, 'key_usage': ['digital_signature'], 'extended_key_usage': [],
-            'subject': 'name', 'sans': []}
+            'subject': 'name', 'sans': [], 'policies': []}
 
 #: The built-in templates; pki.templates changes their options and adds templates of its own.
 PKI_TEMPLATES = {
@@ -179,6 +194,12 @@ CA_NAME_MAX = 64
 #: What / and /status of the web service show, web.status_content, from the least to the most.
 STATUS_CONTENTS = ('basic', 'standard', 'full')
 
+#: A system user the shell of the web service runs as, web.shell_user; root is refused.
+SHELL_USER = re.compile(r'^[a-z_][a-z0-9_-]{0,31}$')
+
+#: The longest web.shell_idle_minutes, a day.
+SHELL_IDLE_MAX = 1440
+
 DOCKER_MODES = ('auto', 'on', 'off')
 
 OPENVPN_PROTOCOLS = ('udp', 'tcp')
@@ -462,6 +483,15 @@ def validate(cfg):
         raise ConfigError(
             f'web.status_content: {status_content!r} is not one of {", ".join(STATUS_CONTENTS)}')
 
+    shell_user = _get(cfg, 'web', 'shell_user')
+    if shell_user and (not SHELL_USER.match(shell_user) or shell_user == 'root'):
+        raise ConfigError(f'web.shell_user: {shell_user!r} is not a system user name other than root')
+    if _get(cfg, 'web', 'shell') and not shell_user:
+        raise ConfigError('web.shell needs web.shell_user, the system user the shell runs as')
+    shell_idle = _get(cfg, 'web', 'shell_idle_minutes')
+    if not 1 <= shell_idle <= SHELL_IDLE_MAX:
+        raise ConfigError(f'web.shell_idle_minutes: {shell_idle} is not between 1 and {SHELL_IDLE_MAX}')
+
     https_ports = []
     for option in ('web_port', 'manager_port'):
         port = _get(cfg, 'https', option)
@@ -501,6 +531,14 @@ def validate(cfg):
         raise ConfigError('pki.publish: http is served by the web service, which needs web.enabled')
     if set(publish) - {'http'} and not _get(cfg, 'https', 'enabled'):
         raise ConfigError('pki.publish: http-80, https and https-default are served by Caddy, which needs https.enabled')
+    for name, oid in cfg['pki']['extended_key_usages'].items():
+        prefix = f'pki.extended_key_usages.{name}'
+        if not EKU_NAME.match(name) or name in EXTENDED_KEY_USAGES:
+            raise ConfigError(f'{prefix}: an extended key usage name starts with a lowercase letter, has at most 31 '
+                              'lowercase letters, digits, hyphens and underscores, and is not a built-in one')
+        if not isinstance(oid, str) or not OID.match(oid):
+            raise ConfigError(f'{prefix} must be an OID in dotted form, such as 1.3.6.1.4.1.311.20.2.2')
+    usages = extended_key_usages(cfg)
     for name, template in cfg['pki']['templates'].items():
         prefix = f'pki.templates.{name}'
         if not PKI_NAME.match(name):
@@ -516,11 +554,14 @@ def validate(cfg):
             raise ConfigError(f'{prefix}.key: {template["key"]!r} is not one of {", ".join(PKI_KEYS)}')
         if not 1 <= template['days'] <= 36500:
             raise ConfigError(f'{prefix}.days must be 1 to 36500 days')
-        for option, allowed in (('key_usage', KEY_USAGES), ('extended_key_usage', EXTENDED_KEY_USAGES),
+        for option, allowed in (('key_usage', KEY_USAGES), ('extended_key_usage', tuple(usages)),
                                 ('sans', SAN_TYPES)):
             for item in template[option]:
                 if item not in allowed:
                     raise ConfigError(f'{prefix}.{option}: {item!r} is not one of {", ".join(allowed)}')
+        for item in template['policies']:
+            if not OID.match(item):
+                raise ConfigError(f'{prefix}.policies: {item!r} is not an OID in dotted form, such as 1.3.6.1.4.1.99999.1')
         if not template['key_usage']:
             raise ConfigError(f'{prefix}.key_usage needs at least one usage')
         if template['subject'] not in TEMPLATE_SUBJECTS:
@@ -664,6 +705,13 @@ def pki_templates(cfg):
             for name in [*PKI_TEMPLATES, *(name for name in custom if name not in PKI_TEMPLATES)]}
 
 
+def extended_key_usages(cfg):
+    """The extended key usages templates may give, name -> OID: the built-in ones (EXTENDED_KEY_USAGES) and those of
+    pki.extended_key_usages."""
+    custom = cfg['pki']['extended_key_usages']
+    return {**EXTENDED_KEY_USAGES, **{name: oid for name, oid in custom.items() if isinstance(oid, str)}}
+
+
 def issuing_cas(cfg):
     """The issuing CAs, name -> {name, templates, acme, builtin}: p2s and s2s (BUILTIN_CAS) with their common names from
     the pki section, then those of pki.issuing_cas, each filled from ISSUING_CA."""
@@ -1011,6 +1059,7 @@ def configure(cfg=None, public_ip=None):
 
     changed = set()
 
+    # Without the directory, which holds the PKI, the copies of the last run stay and what needs none is configured.
     with vpnrouter_pki.locked():
         try:
             notices = vpnrouter_pki.provision(cfg, ctx)
@@ -1018,6 +1067,8 @@ def configure(cfg=None, public_ip=None):
                 changed.add('swanctl')
         except vpnrouter_pki.Failure as failure:
             fail(str(failure))
+        except ldap.LDAPError as exc:
+            notices = [f'the PKI is left as it is: the directory cannot be reached: {exc}']
     for notice in notices:
         warn(notice)
     # What needs the router's own certificates.

debian-package/src/usr/lib/vpn-router/vpnrouter_ldap.py

@@ -11,6 +11,9 @@ The password policy locks an account for LOCKOUT_SECONDS after LOCKOUT_FAILURES
 a successful bind clears the count. slapd's otp overlay is configured on the database, so a
 bind of a user with a TOTP token takes the password followed by a current code.
 cn=totp,ou=policies holds the TOTP parameters the token of every user points to.
+
+ou=pki holds the router's PKI (vpnrouter_pki): an entry per CA, and under it an entry per
+certificate the CA issued. Private keys are readable by root alone, the database's root DN.
 """
 
 import os
@@ -29,6 +32,7 @@ USERS = f'ou=users,{BASE}'
 GROUPS = f'ou=groups,{BASE}'
 SERVICES = f'ou=services,{BASE}'
 POLICIES = f'ou=policies,{BASE}'
+PKI = f'ou=pki,{BASE}'
 DEFAULT_POLICY = f'cn=default,{POLICIES}'
 TOTP_PARAMS = f'cn=totp,{POLICIES}'
 MANAGER = f'cn=user-manager,{SERVICES}'
@@ -54,16 +58,43 @@ OVERLAYS = ('ppolicy', 'otp')
 #: under .1 and object classes under .2. vpnRouterAccount, auxiliary, adds properties of the
 #: package to a user of either kind: mail, for a Manager-only account, vpnRouterScope,
 #: authorization scopes, of which service marks a service account, and displayName and
-#: description, the labels of a service account.
+#: description, the labels of a service account. vpnRouterAuthority is a CA of the PKI: its
+#: certificate and CRL (cACertificate and certificateRevocationList of RFC 4523), its key, the
+#: CSR it waits with for the offline root, the number of its last CRL, where the CRL came from,
+#: and when it was retired. vpnRouterCertificate is a certificate a CA issued, named by its
+#: serial number: the certificate, the key the router keeps for its own and the users'
+#: certificates, its kind, template, names and expiry, and its revocation.
 SCHEMA_OID = '2.25.98477352595735834532404256531620013001'
 SCHEMA_NAME = 'vpn-router'
+_STRING = 'EQUALITY caseIgnoreMatch SYNTAX 1.3.6.1.4.1.1466.115.121.1.15{256} SINGLE-VALUE'
+_TIME = 'EQUALITY generalizedTimeMatch ORDERING generalizedTimeOrderingMatch SYNTAX 1.3.6.1.4.1.1466.115.121.1.24 SINGLE-VALUE'
+_OCTETS = 'EQUALITY octetStringMatch SYNTAX 1.3.6.1.4.1.1466.115.121.1.40 SINGLE-VALUE'
 SCHEMA_ATTRIBUTE_TYPES = (
     f"( {SCHEMA_OID}.1.1 NAME 'vpnRouterScope' DESC 'VPN router: an authorization scope of the account' "
     "EQUALITY caseIgnoreMatch SUBSTR caseIgnoreSubstringsMatch SYNTAX 1.3.6.1.4.1.1466.115.121.1.15{256} )",
+    f"( {SCHEMA_OID}.1.2 NAME 'vpnRouterPrivateKey' DESC 'VPN router: a private key, PEM' {_OCTETS} )",
+    f"( {SCHEMA_OID}.1.3 NAME 'vpnRouterCertificateRequest' DESC 'VPN router: the CSR of a CA, PEM' {_OCTETS} )",
+    f"( {SCHEMA_OID}.1.4 NAME 'vpnRouterCRLNumber' DESC 'VPN router: the number of the last CRL of a CA' "
+    "EQUALITY integerMatch SYNTAX 1.3.6.1.4.1.1466.115.121.1.27 SINGLE-VALUE )",
+    f"( {SCHEMA_OID}.1.5 NAME 'vpnRouterCRLSource' DESC 'VPN router: signed or uploaded, where the CRL of a CA came from' {_STRING} )",
+    f"( {SCHEMA_OID}.1.6 NAME 'vpnRouterRetired' DESC 'VPN router: when a CA was retired' {_TIME} )",
+    f"( {SCHEMA_OID}.1.7 NAME 'vpnRouterKind' DESC 'VPN router: ca, router, user or external, the kind of a certificate' {_STRING} )",
+    f"( {SCHEMA_OID}.1.8 NAME 'vpnRouterTemplate' DESC 'VPN router: the template of a certificate' {_STRING} )",
+    f"( {SCHEMA_OID}.1.9 NAME 'vpnRouterSubjectAltName' DESC 'VPN router: a subject alternative name of a certificate' "
+    "EQUALITY caseIgnoreMatch SYNTAX 1.3.6.1.4.1.1466.115.121.1.15{256} )",
+    f"( {SCHEMA_OID}.1.10 NAME 'vpnRouterNotAfter' DESC 'VPN router: when a certificate expires' {_TIME} )",
+    f"( {SCHEMA_OID}.1.11 NAME 'vpnRouterRevoked' DESC 'VPN router: when a certificate was revoked' {_TIME} )",
+    f"( {SCHEMA_OID}.1.12 NAME 'vpnRouterRevocationReason' DESC 'VPN router: why a certificate was revoked' {_STRING} )",
 )
 SCHEMA_OBJECT_CLASSES = (
     f"( {SCHEMA_OID}.2.1 NAME 'vpnRouterAccount' DESC 'VPN router: properties of a user or a Manager-only account' "
     "SUP top AUXILIARY MAY ( mail $ vpnRouterScope $ displayName $ description ) )",
+    f"( {SCHEMA_OID}.2.2 NAME 'vpnRouterAuthority' DESC 'VPN router: a CA of the PKI' SUP top STRUCTURAL MUST cn "
+    "MAY ( cACertificate $ certificateRevocationList $ vpnRouterPrivateKey $ vpnRouterCertificateRequest $ "
+    "vpnRouterCRLNumber $ vpnRouterCRLSource $ vpnRouterRetired ) )",
+    f"( {SCHEMA_OID}.2.3 NAME 'vpnRouterCertificate' DESC 'VPN router: a certificate a CA of the PKI issued' SUP top "
+    "STRUCTURAL MUST serialNumber MAY ( cn $ userCertificate $ vpnRouterPrivateKey $ vpnRouterKind $ vpnRouterTemplate $ "
+    "vpnRouterSubjectAltName $ vpnRouterNotAfter $ vpnRouterRevoked $ vpnRouterRevocationReason ) )",
 )
 
 #: The TOTP parameters: digits, the OID of HMAC-SHA1, seconds per time step, and the time steps accepted before and after now.
@@ -74,6 +105,7 @@ TOTP_WINDOW = 1
 
 #: The ACLs of the database, in order.
 ACCESS = (
+    'to attrs=vpnRouterPrivateKey by * none',
     f'to attrs=userPassword by dn.exact="{MANAGER}" =wx by self =wx by anonymous auth by * none',
     f'to attrs=oathSecret by dn.exact="{MANAGER}" =w by * none',
     f'to dn.subtree="{USERS}" by dn.exact="{MANAGER}" manage by * read',
@@ -126,20 +158,27 @@ def _ensure_modules(connection):
 
 
 def _ensure_schema(connection):
-    """Add the package's schema to cn=config when missing, else set its definitions that differ."""
+    """Add the package's schema to cn=config when missing, else add the definitions it lacks; a definition that differs
+    from the one of the same OID replaces the whole list of its kind."""
     found = connection.search_s('cn=schema,cn=config', ldap.SCOPE_ONELEVEL, f'(cn=*{SCHEMA_NAME})',
                                 ['olcAttributeTypes', 'olcObjectClasses'])
-    attributes = {'olcAttributeTypes': [value.encode() for value in SCHEMA_ATTRIBUTE_TYPES],
+    attributes = {'olcAttributeTypes': list(SCHEMA_ATTRIBUTE_TYPES), 'olcObjectClasses': list(SCHEMA_OBJECT_CLASSES)}
-                  'olcObjectClasses': [value.encode() for value in SCHEMA_OBJECT_CLASSES]}
     if not found:
         connection.add_s(f'cn={SCHEMA_NAME},cn=schema,cn=config', ldap.modlist.addModlist(
-            dict(attributes, objectClass=[b'olcSchemaConfig'], cn=[SCHEMA_NAME.encode()])))
+            dict({name: [value.encode() for value in values] for name, values in attributes.items()},
+                 objectClass=[b'olcSchemaConfig'], cn=[SCHEMA_NAME.encode()])))
         return
     dn, current = found[0]
-    changes = [(ldap.MOD_REPLACE, name, values) for name, values in attributes.items()
+    for name, wanted in attributes.items():
-               if unordered(current.get(name, [])) != [value.decode() for value in values]]
+        present = unordered(current.get(name, []))
-    if changes:
+        oids = {value.split()[1] for value in present}
-        connection.modify_s(dn, changes)
+        missing = [value for value in wanted if value not in present]
+        if not missing:
+            continue
+        if any(value.split()[1] in oids for value in missing):
+            connection.modify_s(dn, [(ldap.MOD_REPLACE, name, [value.encode() for value in wanted])])
+        else:
+            connection.modify_s(dn, [(ldap.MOD_ADD, name, [value.encode() for value in missing])])
 
 
 def _ensure_password_hash(connection):
@@ -230,7 +269,7 @@ def provision():
         database = _ensure_database(connection)
         _ensure_overlays(connection, database)
         _ensure_entry(connection, BASE, {'objectClass': [b'dcObject', b'organization'], 'dc': [b'vpn-router'], 'o': [b'vpn-router']})
-        for unit in (USERS, GROUPS, SERVICES, POLICIES):
+        for unit in (USERS, GROUPS, SERVICES, POLICIES, PKI):
             _ensure_entry(connection, unit, {'objectClass': [b'organizationalUnit'], 'ou': [unit.split(',')[0][3:].encode()]})
         _ensure_entry(connection, DEFAULT_POLICY, {
             'objectClass': [b'organizationalRole', b'pwdPolicy'],

debian-package/src/usr/lib/vpn-router/vpnrouter_users.py

@@ -3,7 +3,8 @@
 A user is an entry in ou=users of the router's directory, of one of two kinds, fixed when it is
 added. A VPN user is an inetOrgPerson with a first name, a last name and an e-mail address, whose
 password OpenVPN checks, and a client certificate of the P2S issuing CA (vpnrouter_pki) with the
-user name as its common name, which OpenVPN and IKEv2 accept. A Manager-only account is an account,
+user name as its common name, which OpenVPN and IKEv2 accept; the certificate is the entry's
+userCertificate, and the PKI keeps it with its key. A Manager-only account is an account,
 simpleSecurityObject and vpnRouterAccount (the package's schema) with a name, a password and
 optionally an e-mail address, no names, no certificate and so no VPN access; it is added when
 neither the first nor the last name is given, and can sign in to the web service. A service
@@ -68,7 +69,7 @@ PERSON = (('first_name', 'givenName'), ('last_name', 'sn'), ('email', 'mail'))
 LABELS = (('display_name', 'displayName'), ('description', 'description'))
 #: The attributes read for a user.
 ATTRIBUTES = ['uid', 'objectClass', 'pwdAccountLockedTime', 'givenName', 'sn', 'mail', 'oathTOTPToken', 'vpnRouterScope',
-              'displayName', 'description']
+              'displayName', 'description', 'userCertificate;binary']
 #: The vpnRouterScope of a service account.
 SERVICE_SCOPE = 'service'
 #: The object classes of a VPN user and of a Manager-only account.
@@ -173,9 +174,6 @@ def dn_of(name):
     return f'uid={name},{vpnrouter_ldap.USERS}'
 
 
-def certificate(name):
-    return vpnrouter_pki.user_files(name)
-
 
 def entry(connection, name):
     """The attributes of the user's entry; Failure with status 3 when there is none."""
@@ -234,7 +232,7 @@ def summary(attributes):
         'internal': service(attributes) and name in internal_accounts(),
         'enabled': lock != LOCKED,
         'locked': lock not in (None, LOCKED) and locked_since(lock) > time.time() - vpnrouter_ldap.LOCKOUT_SECONDS,
-        'certificate': certificate(name)[0].is_file(),
+        'certificate': 'userCertificate;binary' in attributes,
         'otp': 'oathTOTPToken' in attributes,
     }
     for key, attribute in PERSON + LABELS:
@@ -468,9 +466,10 @@ def profile(connection, name):
     cfg = vpnrouter.load_config()
     if not cfg['openvpn']['enabled']:
         raise Failure('OpenVPN is not enabled', 2)
-    cert, key = certificate(name)
+    credentials = vpnrouter_pki.user_credentials(name)
-    if not cert.is_file() or not key.is_file():
+    if credentials is None:
         raise Failure(f'user {name} has no certificate')
+    cert, key = (value.decode() for value in credentials)
     fqdn = cfg['wan']['local_fqdn'].strip()
     text = '\n'.join([
         'client',
@@ -486,8 +485,8 @@ def profile(connection, name):
         'auth-nocache',
         'verb 3',
         '<ca>', extract_pem(vpnrouter_pki.OPENVPN_CA.read_text(encoding='utf-8')), '</ca>',
-        '<cert>', extract_pem(cert.read_text(encoding='utf-8')), '</cert>',
+        '<cert>', extract_pem(cert), '</cert>',
-        '<key>', key.read_text(encoding='utf-8').strip(), '</key>',
+        '<key>', key.strip(), '</key>',
         '',
     ])
     return {'name': name, 'profile': text}

debian-package/src/usr/lib/vpn-router/web

@@ -8,6 +8,8 @@ Pages:
   /        the status for people: plain text for curl and wget, a styled page
            (Tailwind CSS from a CDN) for a browser
   /status  the status as JSON
+  /status/full
+           the whole status as JSON, whatever web.status_content says, for the Router Manager
   /config  the configuration without its secrets, and what the router resolved and
            runs, with the installed Caddy and where it comes from, as JSON
   /users   the users in the router's directory, whether or not a P2S system is enabled: list,
@@ -32,6 +34,9 @@ Pages:
   /pki/<name>.crt, /pki/<name>.crl
            the DER certificate and CRL of the root (root) and of each issuing CA, which the
            certificates name in their AIA and CRL distribution points; no authentication
+  /shell   while web.shell is true, a login shell of web.shell_user on a terminal: POST signs the
+           user in again for a one-time ticket (see shell_ticket()), GET with it is a WebSocket
+           that carries the terminal (see Handler.shell())
   /auth   sign-in with a user's password and TOTP code, refresh and sign-out (see auth())
   /metrics/history
            the metrics the metrics service keeps, for a view: hour, day, month or year (see
@@ -40,7 +45,7 @@ Pages:
            the databases of each PostgreSQL cluster on the router with their sizes, as JSON (see
            postgresql_databases()); /config has the clusters' settings
 
-/config, /metrics/history, /postgresql, /users, /service-accounts, /groups, /site-to-site, /backup, /ca and /account need an HS256 JWT in an Authorization: Bearer header signed
+/status/full, /config, /metrics/history, /postgresql, /users, /service-accounts, /groups, /site-to-site, /backup, /ca, /shell and /account need an HS256 JWT in an Authorization: Bearer header signed
 with vpnrouter_auth.WEB_KEY (see vpnrouter_auth.verify). A token of /auth names a user in sub;
 /account serves that user, and the other paths need a member of vpnrouter_users.ADMIN_GROUP. A
 token of vpn-router-token has the admin claim and names no user; it may call every path but
@@ -54,9 +59,9 @@ default the address the call came in on, is the last entry of its X-Forwarded-Fo
 default, the overall status, the time and the client's address (its address as for the rate limit
 below); standard also the package version, the installed version of vpn-router-manager
 (manager_version, null when it is not installed) and the number of active and other services; full
-whether each service runs, whether Docker is installed, and the state of each site-to-site connection, road-warrior
+whether each service runs, whether Docker is installed, how many of the site-to-site connections are established
-(IPsec P2S), OpenVPN and WireGuard. No configuration data or key is shown, and no address but the
+(site_to_site: connections and established, null when swanctl cannot be asked), and road-warrior (IPsec P2S), OpenVPN
-client's.
+and WireGuard. No configuration data, key or connection name is shown, and no address but the client's.
 
 The service first initializes, without listening: it makes the signing key and the refresh
 tokens' database (vpnrouter_auth), retrying every INIT_RETRY_SECONDS until both are ready and
@@ -74,13 +79,23 @@ key, the configuration, and the features of the router and the facts shown by /c
 the router has no features, and /config shows no configuration or interfaces.
 """
 
+import base64
 import collections
 import configparser
+import fcntl
+import hashlib
 import json
 import os
+import pwd
+import secrets
+import select
 import shutil
 import signal
+import socket
+import struct
+import subprocess
 import sys
+import termios
 import threading
 import time
 import urllib.parse
@@ -142,6 +157,18 @@ PKI_STATUS = {2: 400, 3: 404, 4: 409}
 #: A file /pki/ serves: the certificate or the CRL of a CA, and its content type.
 PUBLISHED = {'.crt': 'application/pkix-cert', '.crl': 'application/pkix-crl'}
 
+#: Seconds a ticket of POST /shell may open a shell.
+SHELL_TICKET_SECONDS = 30
+
+#: The largest WebSocket message accepted from a client, in bytes.
+MESSAGE_LIMIT = 65536
+
+#: The GUID of RFC 6455 that the Sec-WebSocket-Accept of a handshake is made with.
+WEBSOCKET_GUID = '258EAFA5-E914-47DA-95CA-C5AB0DC85B11'
+
+#: WebSocket opcodes.
+TEXT, BINARY, CLOSE, PING, PONG = 1, 2, 8, 9, 10
+
 _cache = {'at': 0.0, 'data': None}
 _lock = threading.Lock()
 
@@ -149,6 +176,10 @@ _lock = threading.Lock()
 _auth_calls = collections.defaultdict(collections.deque)
 _auth_lock = threading.Lock()
 
+#: The unused tickets of POST /shell: ticket -> (user, monotonic time of expiry).
+_shell_tickets = {}
+_shell_lock = threading.Lock()
+
 
 def read_json(path):
     """The object in a JSON file, or {} when the file is missing or holds no object."""
@@ -232,8 +263,9 @@ def collect(state):
     }
     names = state.get('site_to_site')
     if isinstance(names, list) and names:
-        status['site_to_site'] = {'connections': {name: None if count is None else count > 0
+        counts = established_each(names).values()
-                                                  for name, count in established_each(names).items()}}
+        status['site_to_site'] = {'connections': len(names),
+                                  'established': None if None in counts else sum(1 for count in counts if count)}
     if state.get('p2s'):
         status['p2s'] = {'clients': established('road-warrior')}
     if state.get('wireguard'):
@@ -399,8 +431,9 @@ def text_of(status):
         docker = status['docker']
         lines.append('Docker: not installed' if not docker['installed']
                      else f'Docker: installed, service {docker["service"]}, rules {docker["rules"]}')
-    for name, value in status.get('site_to_site', {}).get('connections', {}).items():
+    if 'site_to_site' in status:
-        lines.append(f'Site to site {name}: {"unknown" if value is None else "established" if value else "not established"}')
+        established, connections = status['site_to_site']['established'], status['site_to_site']['connections']
+        lines.append(f'Site to site: {"unknown" if established is None else established} of {connections} established')
     if 'p2s' in status:
         clients = status['p2s']['clients']
         lines.append(f'Road-warrior (IPsec P2S): {"unknown" if clients is None else f"{clients} connected"}')
@@ -779,15 +812,18 @@ def backup(method, path, body):
 def ca(method, path, body):
     """Answer a /ca request with vpnrouter_pki: the HTTP status and the JSON document.
 
-      GET  /ca                                  {"settings", "templates", "status", "certificates"}: the pki section,
+      GET  /ca                                  {"settings", "templates", "extended_key_usages", "status",
-                                                the templates with the built-in ones, the root, the issuing CAs, the
+                                                "certificates"}: the pki section, the templates with the built-in
-                                                retired CAs and the warnings (vpnrouter_pki.status), and the
+                                                ones, the extended key usages, each {oid, builtin}, the root, the
-                                                certificates issued, newest first
+                                                issuing CAs, the retired CAs and the warnings (vpnrouter_pki.status),
+                                                and the certificates issued, newest first
       PUT  /ca                                  change any of the settings of the pki section
       POST /ca/certificates                     issue a certificate: {"ca", "template", "csr"} answers {"serial",
                                                 "certificate", "chain"}; {"ca", "template", "subject", "sans",
                                                 "password"} answers {"serial", "pfx"}, a PKCS#12 file in base64
       POST /ca/certificates/<serial>/revoke     revoke a certificate: {"reason"?}
+      GET  /ca/bundle/<name>                    the PEM certificates a client trusts the CA with: {"name", "pem"}; for
+                                                root the root alone, for an issuing CA the issuing CA and the root
       GET  /ca/issuing/<name>/csr               the CSR of an issuing CA that waits for the offline root, with the
                                                 openssl extensions to sign it with: {"name", "csr", "extensions"}
       PUT  /ca/issuing/<name>/certificate       take its certificate signed by the root: {"certificate"}
@@ -803,8 +839,12 @@ def ca(method, path, body):
     route = (method, *parts[1:])
     try:
         cfg = vpnrouter.load_config()
+        if len(route) == 3 and route[:2] == ('GET', 'bundle'):
+            return 200, vpnrouter_pki.bundle(route[2])
         if route == ('GET',):
             return 200, {'settings': cfg['pki'], 'templates': vpnrouter.pki_templates(cfg),
+                         'extended_key_usages': {name: {'oid': oid, 'builtin': name in vpnrouter.EXTENDED_KEY_USAGES}
+                                                 for name, oid in vpnrouter.extended_key_usages(cfg).items()},
                          'status': vpnrouter_pki.status(cfg), 'certificates': vpnrouter_pki.certificates()}
         if route == ('PUT',):
             settings = {option: body[option] for option in vpnrouter.SCHEMA['pki'] if option in body}
@@ -836,6 +876,8 @@ def ca(method, path, body):
         return 400, {'error': str(exc)}
     except vpnrouter_pki.Failure as failure:
         return PKI_STATUS.get(failure.status, 500), {'error': str(failure)}
+    except ldap.LDAPError as exc:
+        return 500, {'error': f'the directory, which holds the PKI, failed: {exc}'}
     except OSError as exc:
         return 500, {'error': f'the PKI cannot be changed: {exc}'}
     except SystemExit as exc:
@@ -979,6 +1021,68 @@ def auth(path, body):
         return 500, {'error': str(exc.code)}
 
 
+def shell_ticket(name, body):
+    """Answer POST /shell: the HTTP status and the JSON document.
+
+    The user named by the token signs in again with {"password", "code"?}; a wrong password or code is 403 and counts
+    as a failed login. The answer is {"ticket", "expires_in"}: a ticket that opens one shell (GET /shell) for the
+    same user within SHELL_TICKET_SECONDS. 403 while web.shell is false.
+    """
+    if not isinstance(name, str):
+        return 403, {'error': 'the shell needs a token of a signed-in user'}
+    if not isinstance(body, dict):
+        return 400, {'error': 'the body must be a JSON object'}
+    try:
+        if not vpnrouter.load_config()['web']['shell']:
+            return 403, {'error': 'the shell is disabled; vpn-config-edit set web.shell true enables it'}
+        vpnrouter_users.login(name, body.get('password'), body.get('code'))
+    except vpnrouter_users.Failure as failure:
+        if failure.status == 5:
+            return 403, {'error': 'the password or the code is wrong'}
+        return USER_STATUS.get(failure.status, 500), {'error': str(failure)}
+    except (ldap.LDAPError, OSError) as exc:
+        return 500, {'error': f'the user directory failed: {exc}'}
+    except SystemExit as exc:
+        return 500, {'error': str(exc.code)}
+    ticket = secrets.token_urlsafe(32)
+    now = time.monotonic()
+    with _shell_lock:
+        for unused in [key for key, (_, expires) in _shell_tickets.items() if expires <= now]:
+            del _shell_tickets[unused]
+        _shell_tickets[ticket] = (name, now + SHELL_TICKET_SECONDS)
+    return 200, {'ticket': ticket, 'expires_in': SHELL_TICKET_SECONDS}
+
+
+def take_ticket(name, ticket):
+    """Whether the ticket of POST /shell is unexpired and was given to the user; it is used up either way."""
+    with _shell_lock:
+        holder, expires = _shell_tickets.pop(ticket, (None, 0.0))
+    return holder == name and expires > time.monotonic()
+
+
+def shell_command(account, unit):
+    """The command that runs the login shell of the system user account in the transient unit, on its terminal.
+
+    setsid makes the terminal the controlling one of systemd-run, which passes the window size on; systemd-run starts
+    the shell outside the web service's sandbox, in a PAM login session of the user.
+    """
+    return ['setsid', '--ctty', 'systemd-run', '--quiet', '--collect', '--pty', '--send-sighup', f'--unit={unit}',
+            f'--uid={account.pw_name}', '--property=PAMName=login', f'--working-directory={account.pw_dir}',
+            '--setenv=TERM=xterm-256color', account.pw_shell or '/bin/sh', '-l']
+
+
+def frame(opcode, payload):
+    """A final, unmasked WebSocket frame of a server."""
+    size = len(payload)
+    if size < 126:
+        length = bytes([size])
+    elif size < 65536:
+        length = bytes([126]) + size.to_bytes(2, 'big')
+    else:
+        length = bytes([127]) + size.to_bytes(8, 'big')
+    return bytes([0x80 | opcode]) + length + payload
+
+
 def auth_wait(address):
     """Seconds until the client address may call /auth again, 0 when it may now; a call that may is counted."""
     now = time.monotonic()
@@ -1026,6 +1130,161 @@ class Handler(BaseHTTPRequestHandler):
             return 500, f'the user directory failed: {exc}'
         return (403, reason) if reason else None
 
+    def exact(self, size):
+        """The next size bytes from the client; ConnectionError when it closes first."""
+        data = self.rfile.read(size)
+        if len(data) != size:
+            raise ConnectionError('the client closed the connection')
+        return data
+
+    def message(self, send):
+        """The opcode and the payload of the client's next WebSocket data message, or CLOSE and its payload.
+
+        Fragments are joined and unmasked; a ping is answered with send, a pong ignored. ValueError for an unmasked
+        frame or a message over MESSAGE_LIMIT.
+        """
+        opcode, payload = None, b''
+        while True:
+            head = self.exact(2)
+            code, size = head[0] & 0x0F, head[1] & 0x7F
+            if not head[1] & 0x80:
+                raise ValueError('a frame of the client is not masked')
+            if size == 126:
+                size = int.from_bytes(self.exact(2), 'big')
+            elif size == 127:
+                size = int.from_bytes(self.exact(8), 'big')
+            if len(payload) + size > MESSAGE_LIMIT:
+                raise ValueError(f'a message is larger than {MESSAGE_LIMIT} bytes')
+            mask = self.exact(4) * (size // 4 + 1)
+            data = bytes(byte ^ key for byte, key in zip(self.exact(size), mask))
+            if code == PING:
+                send(PONG, data)
+                continue
+            if code == PONG:
+                continue
+            if code == CLOSE:
+                return CLOSE, data
+            opcode = code if opcode is None else opcode
+            payload += data
+            if head[0] & 0x80:
+                return opcode, payload
+
+    def shell(self, name):
+        """Answer GET /shell?ticket=<ticket>, a WebSocket handshake, with a login shell of web.shell_user on a terminal.
+
+        The ticket must come from POST /shell for the user named by the token. Binary messages of the client are its
+        keystrokes, a text message {"cols", "rows"} sets the window size, and binary messages of the server are the
+        terminal's output. The shell ends after web.shell_idle_minutes without a keystroke, when it exits, or when the
+        client closes the connection; the server then closes it with the reason. Each opening and end is logged.
+        """
+        def refuse(code, message):
+            body = json.dumps({'error': message}).encode() + b'\n'
+            self.send_response(code)
+            self.send_header('Content-Type', 'application/json')
+            self.send_header('Content-Length', str(len(body)))
+            self.end_headers()
+            self.wfile.write(body)
+
+        key = self.headers.get('Sec-WebSocket-Key', '').strip()
+        if self.headers.get('Upgrade', '').lower() != 'websocket' or 'upgrade' not in self.headers.get('Connection', '').lower() \
+                or self.headers.get('Sec-WebSocket-Version') != '13' or not key:
+            return refuse(400, 'GET /shell must be a WebSocket handshake')
+        query = urllib.parse.parse_qs(urllib.parse.urlsplit(self.path).query)
+        if not take_ticket(name, query.get('ticket', [''])[0]):
+            return refuse(403, 'the ticket is not valid; POST /shell gives one')
+        try:
+            options = vpnrouter.load_config()['web']
+        except SystemExit as exc:
+            return refuse(500, str(exc.code))
+        if not options['shell']:
+            return refuse(403, 'the shell is disabled; vpn-config-edit set web.shell true enables it')
+        try:
+            account = pwd.getpwnam(options['shell_user'])
+        except KeyError:
+            return refuse(500, f'the system user {options["shell_user"]} of web.shell_user does not exist')
+        unit = f'vpn-router-shell-{secrets.token_hex(4)}'
+        master, terminal = os.openpty()
+        try:
+            process = subprocess.Popen(shell_command(account, unit), stdin=terminal, stdout=terminal, stderr=terminal,
+                                       env={'PATH': '/usr/sbin:/usr/bin:/sbin:/bin'})
+        except OSError as exc:
+            os.close(master)
+            return refuse(500, f'the shell cannot be started: {exc}')
+        finally:
+            os.close(terminal)
+        accept = base64.b64encode(hashlib.sha1((key + WEBSOCKET_GUID).encode()).digest()).decode()
+        self.send_response(101, 'Switching Protocols')
+        self.send_header('Upgrade', 'websocket')
+        self.send_header('Connection', 'Upgrade')
+        self.send_header('Sec-WebSocket-Accept', accept)
+        self.end_headers()
+        self.close_connection = True
+        client, started, idle = self.client(), time.monotonic(), options['shell_idle_minutes'] * 60
+        log(f'shell of {name} from {client} opened as {account.pw_name} in {unit}')
+
+        lock, ended, typed = threading.Lock(), threading.Event(), [started]
+
+        def send(opcode, payload):
+            with lock:
+                self.wfile.write(frame(opcode, payload))
+
+        def receive():
+            """Pass the client's keystrokes and window sizes to the terminal until it closes the connection."""
+            try:
+                while True:
+                    opcode, payload = self.message(send)
+                    if opcode == CLOSE:
+                        break
+                    if opcode == BINARY:
+                        os.write(master, payload)
+                        typed[0] = time.monotonic()
+                    elif opcode == TEXT:
+                        size = json.loads(payload)
+                        fcntl.ioctl(master, termios.TIOCSWINSZ, struct.pack('HHHH', int(size['rows']), int(size['cols']), 0, 0))
+            except (OSError, ValueError, KeyError, TypeError, struct.error):
+                pass
+            finally:
+                ended.set()
+
+        reader = threading.Thread(target=receive, name=f'{unit} input', daemon=True)
+        reader.start()
+        reason = 'the shell ended'
+        try:
+            while not ended.is_set():
+                left = typed[0] + idle - time.monotonic()
+                if left <= 0:
+                    reason = f'no keystroke for {options["shell_idle_minutes"]} minutes'
+                    break
+                if select.select([master], [], [], min(left, 1))[0]:
+                    try:
+                        output = os.read(master, 65536)
+                    except OSError:
+                        output = b''
+                    if not output:
+                        break
+                    send(BINARY, output)
+            else:
+                reason = 'the client closed the connection'
+        except OSError:
+            reason = 'the connection failed'
+        run('systemctl', 'stop', unit)
+        try:
+            send(CLOSE, (1000).to_bytes(2, 'big') + reason.encode()[:120])
+        except OSError:
+            pass
+        try:
+            self.connection.shutdown(socket.SHUT_RDWR)
+        except OSError:
+            pass
+        reader.join()
+        os.close(master)
+        try:
+            process.wait(timeout=10)
+        except subprocess.TimeoutExpired:
+            process.kill()
+            process.wait()
+        log(f'shell of {name} from {client} in {unit} ended after {int(time.monotonic() - started)} seconds: {reason}')
+
     def answer(self, send_body):
         path = self.path.split('?', 1)[0]
         extra = []
@@ -1034,9 +1293,9 @@ class Handler(BaseHTTPRequestHandler):
         if self.command not in ('GET', 'HEAD'):
             self.close_connection = True
         directory = next((name for name in ('users', 'service-accounts', 'groups', 'account', 'site-to-site', 'backup',
-                                            'ca')
+                                            'ca', 'shell')
                           if path == f'/{name}' or path.startswith(f'/{name}/')), None)
-        protected = path in ('/config', '/metrics/history', '/postgresql') or directory is not None
+        protected = path in ('/status/full', '/config', '/metrics/history', '/postgresql') or directory is not None
         signing = path in ('/auth', '/auth/refresh', '/auth/logout')
         state = current() if protected or signing else {}
         claims = self.claims(state['key']) if protected and state['key'] else None
@@ -1061,6 +1320,9 @@ class Handler(BaseHTTPRequestHandler):
         elif protected and (refused := self.refusal(claims, path, payload)):
             code, kind = refused[0], 'application/json'
             body = json.dumps({'error': refused[1]}, indent=2).encode() + b'\n'
+        elif path == '/status/full' and self.command in ('GET', 'HEAD'):
+            document = shown(self.status(), 'full', self.client())
+            body, kind, code = json.dumps(document, indent=2).encode() + b'\n', 'application/json', 200
         elif path == '/config' and self.command in ('GET', 'HEAD'):
             body, kind, code = json.dumps(details(state), indent=2).encode() + b'\n', 'application/json', 200
         elif path == '/postgresql' and self.command in ('GET', 'HEAD'):
@@ -1069,6 +1331,12 @@ class Handler(BaseHTTPRequestHandler):
             query = urllib.parse.parse_qs(urllib.parse.urlsplit(self.path).query)
             code, document = metrics_history(query.get('range', ['hour'])[0])
             body, kind = json.dumps(document).encode() + b'\n', 'application/json'
+        elif directory == 'shell' and (path, self.command) == ('/shell', 'GET'):
+            return self.shell(claims.get('sub'))
+        elif directory == 'shell':
+            code, document = shell_ticket(claims.get('sub'), payload) if (path, self.command) == ('/shell', 'POST') \
+                else (404, {'error': f'no route {self.command} {path}'})
+            body, kind = json.dumps(document, indent=2).encode() + b'\n', 'application/json'
         elif directory == 'account':
             code, document = account(claims['sub'], self.command, path, payload)
             body, kind = json.dumps(document, indent=2).encode() + b'\n', 'application/json'

debian-package/src/usr/sbin/vpn-router-ca

@@ -1,13 +1,13 @@
 #!/usr/bin/python3
-"""Manage the router's PKI from the command line, with vpnrouter_pki.
+"""Manage the router's PKI, which the router's directory holds, from the command line, with vpnrouter_pki.
 
 status shows the root, the issuing CAs and the warnings; list the certificates the router issued. issue signs a CSR,
 or makes a key and writes a PFX file whose password is read from the first line of standard input. ca csr prints the
 CSR of an issuing CA that waits for the offline root, with the openssl extensions to sign it with, and ca import takes
 the signed certificate. root export-key writes the root key encrypted with the passphrase read from standard input,
-root remove-key removes it from the router, root import-key puts it back, root import-cert places an existing root's
+root remove-key removes it from the router, root import-key puts it back, and root import-crl takes a root CRL signed
-certificate before the root exists, and root import-crl takes a root CRL signed offline. maintain signs the stale CRLs
+offline. maintain signs the stale CRLs again; vpn-router-pki.service runs it daily. A change that needs
-again; vpn-router-pki.service runs it daily. A change that needs vpn-router-setup restarts it without waiting.
+vpn-router-setup restarts it without waiting.
 
 The answer is text for people on standard output, and a failure is a message on standard error. With --json the answer
 is JSON on standard output, and a failure is {"error": ...} there too. The exit status says what failed: 2 the request
@@ -22,7 +22,6 @@ commands and their options.
   vpn-router-ca [--json] maintain
   vpn-router-ca [--json] ca csr NAME
   vpn-router-ca [--json] ca import NAME FILE
-  vpn-router-ca [--json] root import-cert FILE
   vpn-router-ca [--json] root export-key --out FILE   (passphrase on stdin)
   vpn-router-ca [--json] root remove-key [--yes]
   vpn-router-ca [--json] root import-key FILE   (passphrase on stdin, an empty line for none)
@@ -39,6 +38,8 @@ import sys
 
 sys.path.insert(0, '/usr/lib/vpn-router')
 
+import ldap
+
 import vpnrouter
 import vpnrouter_pki
 from vpnrouter_pki import Failure
@@ -125,10 +126,6 @@ def run(options):
             document = vpnrouter_pki.import_ca(cfg, options.name, pathlib.Path(options.file).read_text(encoding='ascii'))
             restart_setup()
             return document, f'Issuing CA {options.name} has its certificate, which expires {document["expires"]}.'
-        if options.action == 'import-cert':
-            document = vpnrouter_pki.import_root_cert(pathlib.Path(options.file).read_bytes())
-            restart_setup()
-            return document, f'Root CA {document["subject"]} placed, without its key.'
         if options.action == 'export-key':
             data = vpnrouter_pki.export_root_key(secret())
             out = pathlib.Path(options.out)
@@ -177,7 +174,6 @@ def main(argv):
     importer.add_argument('file')
     root = commands.add_parser('root', help='the root CA')
     root_actions = root.add_subparsers(dest='action', required=True, parser_class=Parser)
-    root_actions.add_parser('import-cert', help="place an existing root's certificate").add_argument('file')
     exporter = root_actions.add_parser('export-key', help='write the root key encrypted with the passphrase from stdin')
     exporter.add_argument('--out', required=True, help='the file to write')
     remover = root_actions.add_parser('remove-key', help='remove the root key from the router')
@@ -193,6 +189,8 @@ def main(argv):
         code, message = failure.status, str(failure)
     except OSError as exc:
         code, message = 1, str(exc)
+    except ldap.LDAPError as exc:
+        code, message = 1, f'the directory, which holds the PKI, failed: {exc}'
     except SystemExit as exc:
         code, message = 1, str(exc.code)
     else:

debian-package/src/usr/share/doc/vpn-router/vpn-router.json.example

@@ -61,7 +61,10 @@
     "port": 7081,
     "database": "",
     "trusted_proxies": [],
-    "status_content": "basic"
+    "status_content": "basic",
+    "shell": false,
+    "shell_user": "",
+    "shell_idle_minutes": 15
   },
   "https": {
     "enabled": true,
@@ -92,6 +95,9 @@
         "days": 397
       }
     },
+    "extended_key_usages": {
+      "smartcard_logon": "1.3.6.1.4.1.311.20.2.2"
+    },
     "root_key_warning": true
   },
   "metrics": {