Sign in

Choose the sign-in route available on your machine. If you have just installed Peios, complete first-boot setup first. Manual and legacy installation routes can provision accounts differently; Creating accounts explains those distinctions.

Choose how to connect #

• Use the desktop in a browser: Open the desktop. Check the machine's certificate before entering credentials.
• Use a local console: The login command explains the prompt, live-medium autologon and multiple-console behavior. Switching consoles does not lock or log out the session you leave.
• Use a remote terminal: Sign in over SSH. Verify the host fingerprint and read the access precautions before changing the SSH service or credential policy.

Manage your own account #

Use passwd to change your own password. For your SSH keys, follow Changing your own keys. To change the name shown beside your account name, follow Changing your own display name. Changing another account's credentials is an administration task; start with Manage local accounts and groups.

A stored password and the account's credential policy are separate. Follow Creating accounts when changing whether a password or SSH key is required; setting a password alone does not change a passwordless account's policy.

If sign-in fails #

Start with Troubleshoot a problem. Keep a working administrator route available while investigating. Do not delete the local principal store to try to restore access: it holds the machine's identity, and a corrupt store is different from a missing one. See The local store.

For the model behind the prompts, read How authentication works and Logon sessions in Security Fundamentals.

login is the terminal client for signing in. It collects an identifier, renders whatever credential prompts the authority sends, installs the token it is granted, and replaces itself with your shell.

login [name] [options]
login --try <name> [options]
login --try-no-password <name> [options]

It does not know what a password is. It renders the prompts it is asked to render and returns the answers, so adding a new credential type — a one-time code, a smartcard — changes the authority and leaves login alone.

Naming a principal, or not #

With no name, login asks for one:

Username: alice
Logging in as alice
Password:

With a name, the first prompt is skipped. The Logging in as line comes from the authority rather than from login, so it will gain a realm once authorities have them.

A principal who needs no credential is signed in immediately, with no prompt at all — see passwordless accounts.

--try and --try-no-password #

Both attempt a named principal and fall back to an ordinary prompt rather than failing. They differ in what they offer to collect.

--try <name> attempts the principal with login's full capabilities. A principal whose policy requires no credential is signed in immediately; one whose policy calls for a password is prompted for it.

--try-no-password <name> attempts the principal while declaring that it can collect nothing, so only a principal who needs no credential can succeed. This is what a console autologon uses.

Neither flag asserts that anyone is authenticated. The authority still decides, and understating what you can collect only denies you prompts you could have rendered — so running either by hand gains you nothing you did not already have.

The first two columns below describe credential policy, not just whether a password is stored. They assume an enabled account with console logon permitted and, for password sign-in, a password set.

A fallback restarts the sign-in from Username:, so you are never locked to the principal that was attempted.

When a fallback explains itself #

login says why it fell back only if something was already on your terminal.

A --try that reached a password prompt has interrupted you, and dropping to Username: without a word would read as a fault — you typed a password and got asked for a name. So it reports first:

$ login --try alice
Logging in as alice
Password:
login: Password incorrect
Username:

A --try-no-password that was refused before anything was rendered has interrupted nobody, and stays quiet. That is what keeps a line about a failed autologon off the console of every machine where the principal requires a credential.

Falling back is limited to denials another principal could survive. A failure of the authority itself is reported and login exits, because offering a prompt that cannot work either would spin a console.

Where existence is checked #

login asks /run/ident.sock whether a principal exists, not the logon socket. The logon socket will not tell it — an authority never distinguishes an unknown principal from a bad credential — while the identity socket answers plainly, which is what it is for.

If that lookup cannot be answered, login attempts the sign-in anyway rather than reporting an absence. An unreachable source reported as "no such user" would turn an outage into a fact.

Autologon on a console #

A console that signs in on its own is a passwordless principal plus --try-no-password. On a live image, peinit starts:

/bin/login --console --try-no-password peios

The same service definition suits an image where peios requires a password: the attempt is refused before anything is rendered, and an ordinary prompt appears. No second seed, and no conditional configuration.

To require a password instead of autologon, first set the principal's password with lps password, then select lps policy <name> password. Setting the password alone leaves the none credential policy and autologon unchanged.

Taking --try-no-password out of the login-console service's Arguments stops the automatic attempt, but does not change the account's credential policy: a principal whose policy is still none can still sign in at that prompt without a credential. To move the prompt to another terminal, change the service's TTYPath — see controlling services.

System Settings chooses it in its Startup & Shutdown section, under Console Sign-In: Automatic Sign-In is Off, or one of the local accounts. The choice is written the moment it is made, as Arguments: --console, followed by --try-no-password and the account if one is chosen. It applies the next time login-console starts, at the latest the next boot. Changing it needs write access to Machine\System\Services\login-console, which as shipped only Administrators have.

GXWI information on the console #

Managed login --console sessions show GXWI's browser address and certificate SHA-256 fingerprint before authentication when GXWI is installed. Compare the fingerprint on this trusted local console with the browser's certificate details before accepting its warning. See the machine's certificate.

The banner reads /var/state/gxwi/certificate.sha256 and the configured Machine\Software\GXWI\Listen address and port. With the IPv4 wildcard listener Peios ships (0.0.0.0:7780), it lists the machine's active non-loopback IPv4 addresses. If the value is missing or unreadable, the banner shows GXWI's own fallback, the loopback address 127.0.0.1:7780. An IPv6 wildcard lists IPv6 addresses; link-local addresses that need an interface zone are omitted. A specific listen address is displayed as configured. This is connection information, not a check that GXWI is currently running.

Information is read once each time login starts. Missing or malformed fingerprints and unavailable addresses are reported without preventing login. Ordinary login invocations without --console do not show this banner.

Options #

-f is not implemented. On Linux it means "trust me, they are already authenticated", gated only by the caller being root. On Peios that decision belongs to the authority, taken from the verified peer, so accepting a flag here would put an authentication bypass in an unprivileged process.

The environment your shell starts in #

Without -p, login builds a fresh environment: HOME, SHELL, USER, LOGNAME, PATH=/bin, and TERM. The shell's argv[0] gets a leading dash, which every shell reads as "this is a login shell, run the profile files".

TERM is carried through if login was started with one. Otherwise login decides it from the terminal it is on, the way a getty does elsewhere: linux on a virtual console (/dev/tty1 and its siblings, the display), vt220 on anything else (a serial line, a hypervisor's paravirtual console). /dev/console is whichever of those the kernel chose, and login resolves it through the kernel's own record of the active console rather than guessing, so one service definition on /dev/console gets the right answer on a machine with a display and on one without.

The home directory comes from the profile the authority sent, and a missing one is not fatal. login reports it and starts you in /. Refusing to proceed over an absent directory would turn a cosmetic problem into being locked out.

login does not create it. Two reasons, and either would be enough. It has already made your token its own by the time it changes directory, so it is you rather than the system — and /home lets you walk through it but not create in it. And directory provisioning has no business inside the one program that has to keep working when everything else is broken. The authority creates the directory when it grants the logon, before login is handed anything; reaching this fallback means the authority named no home, or could not make one.

Exit status #

login does not return on success — it replaces itself with your shell, so what you see afterwards is the shell's exit status.

Multiple local consoles #

The Experimental edition provides independent login sessions on tty1, tty2 and tty3. Switch between them with Alt+F1, Alt+F2 and Alt+F3 at a text console, or use chvt 1, chvt 2 and chvt 3 with the required console authority. Switching does not lock or log out the session you leave.

login-console follows the kernel's primary console: peinit resolves a display console to the fixed tty1, or uses the selected serial/paravirtual terminal. It retains the live-medium passwordless peios attempt. Additional services login-tty1, login-tty2 and login-tty3 show ordinary username prompts. On a display-primary machine, the duplicate login-tty1 service is skipped because login-console already owns that terminal. On a serial-primary machine all three local prompts can run alongside the serial session. Missing terminals are skipped.

First-boot setup retains the primary console. Additional terminals wait until both setup service definitions have been removed; they collect no credentials while setup is pending. Logging out terminates that terminal service's remaining processes and produces a fresh prompt with canonical input and echo restored. A normal logout does not consume the crash-restart budget. This resets terminal input settings; it does not implement a session lock or promise to erase all screen history.

passwd changes your own password.

passwd

It takes no arguments. The account it changes is the one you are signed in as: the authority reads it from your token, and the request has no field in which to name anybody else. To set another principal's password, an administrator uses lps password.

What it asks #

$ passwd
Changing the password for alice
Current password:
New password:
Retype new password:
password changed

Your current password is always asked for, even though you are signed in. Being signed in shows that someone authenticated as you; it does not show that the person at the keyboard now is you, and a password changed from an unattended terminal could not be recovered by signing in again.

If the new password and its confirmation differ, or the new one is empty, you are told why and asked again. After three attempts the change ends with the password unchanged.

The prompts come from the principal source that holds your account, not from passwd. passwd renders what it is asked and returns the answers, so a source with different requirements asks for what it needs without passwd changing.

How it works #

passwd opens a credential-change conversation with the authority on /run/logon.sock (PGSS §2.20). authd finds the source that holds your account from your token's SID and relays the conversation to it. lpsd checks your current password, sets the new one, and writes its store to disk before it reports success, so password changed means the next sign-in checks the new password. It records the change as an lpsd.credential.changed event, naming your account by SID, and records a refused change the same way with the reason, such as wrong-credential for a current password that did not verify.

Nothing is minted. Your current session carries on as it was, and so does every other session you hold.

Other ways to change it #

passwd is one client of this conversation, not the only one. A program can hold the same conversation for you. On the desktop, My Settings (type my in the launcher) does: its Password section collects your current password and the new one twice, and hands them over when the authority asks. The line along the bottom of the window shows what the authority said, then whether the password changed, and the fields are emptied whatever happened. An account with no password sees why in place of the form. The authority asks the same questions, applies the same rules and gives the same refusals whichever program asks; only how the questions are shown differs. A program written in Rust gets the conversation from the credential module of libauthd-client, which passwd itself uses.

Adding or removing your own SSH keys is a sibling conversation on the same socket, and asks for your current password the same way: see Changing your own keys.

From a script #

When standard input is not a terminal, passwd prints no prompts and reads one line for each, in order:

printf '%s\n' "$current" "$new" "$new" | passwd

When it refuses #

A message ending whether the password changed is not known means the authority went away after the change was asked for and before it said how it ended. Sign in with each password to find out which one holds.

Who can reach the socket #

Every authenticated principal can connect to /run/logon.sock so that passwd works for them. That does not let them originate a logon for anybody else, which still takes a LogonTypes record on their own policy entry.

A machine whose administrator has replaced the socket's descriptor with LogonSocketDescriptor may not admit you. See assigning privileges.

Exit status #

See also #

• How authentication works — the conversation this is one kind of.
• The lps command — setting another principal's password, as an administrator.
• PGSS §2.20 — the credential-change conversation, specified.

The SSH server lets people sign in to this machine from another over the network, with their password or one of their SSH keys. It is the sshd service, from the dev.peios.openssh package. Every SSH sign-in is a RemoteInteractive logon through the same authority as any other: see How authentication works.

That includes commands without a PTY and SFTP: the account must permit remote-interactive, not just network. An account with credential policy none cannot sign in over SSH. Password authentication requires an actual password and a policy allowing it; key authentication requires an enrolled key and a policy of key or either. The SSH implementation contract records the release-qualification and compatible-build requirements.

Four things about the server are settings:

The port and password sign-in are machine policy in the registry, not lines of sshd_config. start-sshd reads them each time the service starts and gives them to sshd on its command line, and a Port or PasswordAuthentication line in /lcl/etc/ssh/sshd_config has no effect. Other sshd options still go in that file.

Change them with ssh-settings on a terminal, or SSH Settings on the desktop (type ssh in the launcher), which is the same program and does the same things.

Looking #

$ ssh-settings
server       running
port         22
passwords    accepted
host key     SHA256:Wm3…

Anyone may look, except at the host key, which only SYSTEM and Administrators may read; others see why instead.

Connect from another computer #

1. From a trusted administrator session on the Peios console, or a certificate-verified GXWI session as an administrator, read the machine's address, SSH service state, port and host fingerprint:

   Copy

   net status
   ssh-settings
   ssh-settings fingerprint
   

   Check that the server is running. Choose an address on an interface reachable from the other computer; Reading net status explains the interface blocks. For a direct connection, use the port shown by ssh-settings, which is 22 as shipped. The QEMU Makefile's host-forwarded port 2222 is a separate route described in the build quick start.

2. On the other computer, use your account name, the machine's address and that observed port:

   Copy

   ssh -p <observed-port> <name>@<machine-address>
   

   Before accepting a first-connection prompt, compare its SSH host fingerprint with the trusted reading from step 1. This is the SSH host key, not GXWI's TLS certificate fingerprint. If they differ, stop and investigate; do not accept the key or discard a remembered key just to suppress a warning.

3. Sign in with the intended password or enrolled key and check that a new shell opens. A running service or an already-open session alone does not prove that a new sign-in works.

Turning it on and off #

ssh-settings on
ssh-settings off

on sets the service to start at boot and starts it now; off stops it and keeps it from starting. People signed in over SSH are disconnected when it stops. Each needs write access to the service's key, Machine\System\Services\sshd, and the right to start and stop sshd, which as shipped only Administrators have; see who can manage a service. Without the second, the setting is still saved and takes effect at the next boot, and you are told so.

Moving the port #

ssh-settings port 2222

A port is three things that must agree, and ssh-settings changes all three in one registry transaction, so none is ever moved without the others:

• the Port value;
• sshd's port reservation, the descriptor under Machine\System\Network\TcpIp\PortReservations that lets only sshd bind the port (see port reservations);
• the ssh firewall rule, Machine\System\Network\Rules\Flow\ssh, whose DstPort.Equal is the port let in (see network policy).

It then restarts sshd onto the new port, which disconnects everyone signed in over SSH, you too if you are. Connect again on the new port: ssh -p 2222 alice@host.

A port another program has reserved is refused: a reservation naming that one port and nothing else, such as tcp:80 for a web server, makes it that program's. A wider range that contains the port, such as tcp:1-1023, is fine, since reservations nest. Moving the port needs write access to all three keys, which as shipped only Administrators have.

Keys only #

ssh-settings passwords off disables password authentication for SSH. It does not require an account-wide policy of key. Keep the account policy either when its password must also work through GXWI: GXWI does not currently offer SSH-key authentication, so a key-only account cannot use that sign-in path.

With SSH passwords off, an account whose policy is password cannot sign in over SSH, though it can still use its password at the console and on the desktop, subject to its other sign-in restrictions.

Before changing the server:

1. Enroll a key for each person who needs SSH. They can use My Settings where permitted, or an administrator can use lps key add <name> <public-key-file> [label]. Adding a key does not change credential policy. For a password-enabled account that will also use keys, an administrator sets lps policy <name> either; retain that policy if GXWI password access is needed.
2. Inspect lps show <name> and lps key list <name> to check the enabled account, enrolled key, credential policy and permitted remote-interactive logon type. While SSH passwords are still available, make a fresh SSH connection that actually authenticates with the enrolled key, following the host-key check above. A connection that falls back to a password does not count as a key test. If the key test fails, stop before disabling passwords and check those account settings and the service state.
3. Verify a fresh administrator sign-in through a separate non-SSH route, such as the local console or certificate-verified GXWI, and keep that route available. The last-administrator guard does not prove that a usable route exists. Keeping another SSH session open is insufficient: this change restarts sshd and ends every SSH session.

Only after both access paths work, disable SSH passwords:

ssh-settings passwords off

Then make another new key-authenticated SSH connection and verify that its shell opens. If it fails, use the surviving console or GXWI administrator route to inspect the settings and restore SSH password acceptance with ssh-settings passwords on. This reversal also restarts sshd; it does not change account credential policy. Keep the separate administration route until fresh SSH access has been verified again.

The host key #

ssh-settings fingerprint

The first time someone connects, their SSH client shows the server's host key fingerprint and asks whether to trust it. Compare it with this one, read on the machine itself or by someone you trust who can read it, before answering yes. The key is made on the server's first start and never replaced automatically.

On the desktop #

SSH Settings shows the same four things on one page: the server, with how it is and a switch to turn it on or off; Port, with Apply once it is changed; Password Authentication, as a switch; and Host Key Fingerprint, with Copy. Turning the server on happens at once. Anything that restarts or stops it — turning it off, moving the port, password sign-in either way — ends every SSH session, so it asks first, under its row, and changes nothing until it is told to go ahead. What you may not change is shown read-only, with the reason, once. Each change says what it did along the bottom of the window, including whether sshd was restarted.

Exit status #