57_WolveandClaude Opus 5
a3843d3d85
Hardened hosts rejected clients that implement the very same key exchange. The
KEX list was assembled from version arithmetic and emitted only the
standardised spellings:
KexAlgorithms mlkem768x25519-sha256,sntrup761x25519-sha512
OpenSSH called that hybrid sntrup761x25519-sha512@openssh.com before the method
was standardised (8.5, in the default proposal from 8.9) and
sntrup761x25519-sha512 after (9.9), and KEXINIT matches names byte-exactly with
no alias resolution -- so every client older than the rename was refused with
"no matching key exchange method found" despite implementing the algorithm. The
same arithmetic was a latent server-side bug: on OpenSSH 9.0-9.8 it wrote the
post-standardisation name into sshd_config, which those builds do not know, and
sshd fatals on an unknown KexAlgorithms token rather than starting.
Ask the binary instead of guessing. oslib gains kex_supported(),
ssh_kex_pq_list(), ssh_kex_classic_list(), ssh_kex_list() and ssh_kex_has_pq(),
which filter candidates through `ssh -Q kex` and offer every spelling the host
actually has. Version thresholds are gone, and with them both failure modes --
including on distros whose backports make the version string meaningless.
SSH_ALLOW_CLASSIC_KEX=1 (off by default) additionally offers curve25519-sha256
and its @libssh.org spelling. Some clients have no PQ method at all: notably
Windows' in-box ssh.exe, which is not merely old -- Microsoft's fork compiles
sntrup761 out because it needs C99 VLAs that MSVC lacks, so even a fully patched
9.5p2 reports zero PQ methods. The knob is a real trade and says so in the
warning, the generated sshd_config comment, and the README: such a session is
safe against a classical attacker but has no store-now-decrypt-later protection.
Modern clients still negotiate PQ, since the client's preference order decides.
Three defects found reviewing the above, fixed here:
- the printed pre-reload verification command pinned the server's full list via
`-o KexAlgorithms=`, which ssh rejects at option-parse time when the client
lacks any one name. That made the one safety gate before a wholesale
sshd_config swap a false negative for exactly the clients this commit admits.
Dropped, matching harden-jumphost.sh.
- the no-PQ branch was unreachable: without the opt-in the classical names are
never collected, so a host with no PQ hybrid died reporting "no usable key
exchange method" instead of the actionable message written for it. The branch
now keys off a separate PQ probe, and the empty-list die is narrowed to a
genuinely empty `ssh -Q kex`.
- SSH_VER is cosmetic but its grep could abort the whole run under pipefail on
any banner that does not match (vendor forks, OpenSSH_for_Windows_9.5p2) --
silently, with no message. Guarded.
Wired through cloud-init/base.yml and jumphost.yml, since harden-ssh.sh rewrites
sshd_config wholesale on every run and a hand edit there does not survive.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
445 lines
19 KiB
Bash
445 lines
19 KiB
Bash
#!/usr/bin/env bash
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#
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# harden-ssh.sh
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#
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# SSH hardening for Alpine, Debian, and Alma Linux. Run on a fresh box (and,
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# for the simplex relay, BEFORE deploy-simplex.sh).
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#
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# All distro-specific operations go through scripts/oslib.sh. The OS-specific
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# surface for this script is: package install, the sshd service name, the
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# external sftp-server path, host-key keygen suppression (Alpine only), the
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# sshguard log source + firewall backend, and the boot hook that installs the
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# iptables jump. Each is clearly marked.
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#
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# What this does:
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# 1. Generates fresh Ed25519 host keys; removes RSA/ECDSA/DSA host keys
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# 2. Generates an Ed25519 root keypair, installs the public key into
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# /root/.ssh/authorized_keys, and PRINTS the private key to stdout once.
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# 3. Forces post-quantum hybrid KEX only (mlkem768x25519, sntrup761x25519 --
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# every spelling this OpenSSH supports). SSH_ALLOW_CLASSIC_KEX=1 also
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# offers curve25519-sha256 for clients with no PQ method at all.
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# 4. Modern ciphers and MACs only.
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# 5. Disables everything but an interactive terminal + SFTP (no forwarding,
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# tunneling, X11, agent, password auth).
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# 6. Optional non-default port (SSH_PORT).
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# 7. Installs sshguard for brute-force protection.
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# 8. Validates with `sshd -t` and prompts before reloading (so you don't
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# lock yourself out).
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#
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# A note on "quantum-safe": stock OpenSSH gives PQ KEY EXCHANGE (protects the
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# session key against store-now-decrypt-later) but classical Ed25519 AUTH
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# keys -- the strongest practical posture available without breaking client
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# compatibility.
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#
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# Usage:
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# bash harden-ssh.sh # port stays 22
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# SSH_PORT=2222 bash harden-ssh.sh # change port
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# ALLOWED_IP=1.2.3.4 bash harden-ssh.sh # whitelist your client IP
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# FORCE=1 bash harden-ssh.sh # skip the confirm prompt
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# SSH_ALLOW_CLASSIC_KEX=1 bash harden-ssh.sh # also offer curve25519-sha256
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#
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# SSH_ALLOW_CLASSIC_KEX exists for one reason: clients too old for ANY
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# post-quantum KEX. The ssh.exe bundled with Windows is the common case -- its
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# `ssh -Q kex` lists no mlkem or sntrup at all, so it cannot connect to a
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# PQ-only host however the server spells the algorithms. Turning this on is a
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# real trade: a session that negotiates curve25519-sha256 is safe against a
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# classical attacker but has no store-now-decrypt-later protection. Prefer
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# upgrading the client (Git for Windows, WSL, or a current Win32-OpenSSH ship
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# OpenSSH 9.x) and leave this off.
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set -euo pipefail
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# Load the OS abstraction layer (sits next to this script).
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SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
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# shellcheck source=scripts/oslib.sh
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. "$SCRIPT_DIR/oslib.sh"
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# ============================================================================
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# CONFIG
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# ============================================================================
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: "${SSH_PORT:=22}"
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: "${ALLOWED_IP:=}" # optional: your client IP, sshguard-whitelisted
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: "${KEY_COMMENT:=root@$(hostname)-$(date +%Y%m%d)}"
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: "${FORCE:=0}"
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# log()/warn()/die() come from oslib (_log/_warn/_die); alias for readability.
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log() { _log "$@"; }
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warn() { _warn "$@"; }
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die() { _die "$@"; }
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[[ $EUID -eq 0 ]] || die "Run as root."
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os_detect
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log "Detected OS: ${OS_ID} (family ${OS_FAMILY}, init ${INIT_SYSTEM})"
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# ----------------------------------------------------------------------------
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# 1. Pre-flight: ensure an ssh client exists before probing its version
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# ----------------------------------------------------------------------------
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if ! command -v ssh >/dev/null 2>&1; then
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log "ssh not found; installing openssh..."
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install_openssh || die "Could not install OpenSSH; cannot harden. Fix the package error above, then re-run."
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fi
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log "Checking which key exchange methods this OpenSSH supports..."
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# Cosmetic only -- every decision below comes from `ssh -Q kex`, not this. A build
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# whose banner does not match (OpenSSH_for_Windows_9.5p2, vendor forks) must not
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# abort the run: without the guard, grep's non-match fails the pipeline under
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# pipefail and set -e kills the script here with no message at all.
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SSH_VER=$(ssh -V 2>&1 | grep -oE 'OpenSSH_[0-9]+[.][0-9]+' | head -1 | sed 's/OpenSSH_//' || true)
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# Ask the binary what it supports rather than deriving it from the version -- the
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# same algorithm has two spellings and guessing wrong either breaks sshd_config or
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# locks out clients that implement it under the other name. See oslib.
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KEX_PQ="$(ssh_kex_pq_list)"
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KEX_LIST="$(ssh_kex_list)"
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if [[ -n "$KEX_PQ" ]]; then
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if [[ "${SSH_ALLOW_CLASSIC_KEX:-0}" == "1" ]]; then
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KEX_NOTE='# --- Key exchange: post-quantum hybrid + classical fallback ---
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# curve25519-sha256 is offered for clients too old for any PQ method
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# (SSH_ALLOW_CLASSIC_KEX=1). A session that negotiates it has NO store-now-
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# decrypt-later protection -- drop the fallback once those clients are gone.'
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warn "SSH_ALLOW_CLASSIC_KEX=1 -- offering curve25519-sha256 next to the PQ methods."
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warn " Admits clients with no PQ KEX at all (Windows in-box ssh.exe), at the cost of"
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warn " store-now-decrypt-later protection for any session that negotiates it."
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else
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KEX_NOTE='# --- Key exchange: post-quantum hybrid only ---
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# Every classical-only method is rejected, which is what protects the session key
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# against "store now, decrypt later". Clients with no PQ KEX cannot connect --
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# re-run with SSH_ALLOW_CLASSIC_KEX=1 to also offer curve25519-sha256.'
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fi
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else
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# No post-quantum method on this host at all. Decide on THAT, not on an empty
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# list: without the opt-in the classical names are never collected, so an empty
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# list here would otherwise be misreported as "no usable KEX".
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[[ "${SSH_ALLOW_CLASSIC_KEX:-0}" == "1" ]] \
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|| die "OpenSSH ${SSH_VER:-?} has no post-quantum KEX (needs >= 8.5 built with sntrup761). Re-run with SSH_ALLOW_CLASSIC_KEX=1 to accept classical-only."
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[[ -n "$KEX_LIST" ]] \
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|| die "OpenSSH ${SSH_VER:-?} reports no usable key exchange method at all ('ssh -Q kex' returned nothing)."
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KEX_NOTE='# --- Key exchange: CLASSICAL ONLY ---
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# This OpenSSH has no post-quantum method. No store-now-decrypt-later protection.'
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warn "OpenSSH ${SSH_VER:-?} has no PQ KEX -- classical curve25519 only."
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fi
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log "OpenSSH ${SSH_VER:-?}: KexAlgorithms ${KEX_LIST}"
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# ----------------------------------------------------------------------------
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# 2. Install packages (OS-gated inside oslib)
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# ----------------------------------------------------------------------------
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log "Installing OpenSSH server + sshguard + iptables..."
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install_openssh || die "OpenSSH packages failed to install; cannot harden SSH. Fix the package error above, then re-run."
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# sshguard is best-effort: a host where it can't install right now (e.g. EPEL
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# momentarily unreachable) must still get the sshd_config hardening AND the login
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# notifier -- not a silently half-configured box. Warn and press on.
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install_bruteforce_protection \
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|| warn "sshguard not installed; brute-force protection is OFF. Add it later with: dnf install -y epel-release sshguard. Continuing with the rest of the hardening."
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# The external SFTP subsystem binary path differs per distro.
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SFTP_PATH="$(sftp_server_path)"
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[[ -x "$SFTP_PATH" ]] || warn "sftp-server not found at expected path ($SFTP_PATH); SFTP may not work until installed."
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# ----------------------------------------------------------------------------
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# 3. Host keys -- regenerate with Ed25519 only
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# ----------------------------------------------------------------------------
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log "Regenerating host keys (Ed25519 only)..."
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rm -f /etc/ssh/ssh_host_rsa_key* \
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/etc/ssh/ssh_host_ecdsa_key* \
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/etc/ssh/ssh_host_dsa_key*
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if [[ ! -f /etc/ssh/ssh_host_ed25519_key ]]; then
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ssh-keygen -q -t ed25519 -f /etc/ssh/ssh_host_ed25519_key -N "" \
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-C "host@$(hostname)-$(date +%Y%m%d)"
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fi
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chmod 600 /etc/ssh/ssh_host_ed25519_key
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chmod 644 /etc/ssh/ssh_host_ed25519_key.pub
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log "Host key fingerprint (verify on first connect):"
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ssh-keygen -l -f /etc/ssh/ssh_host_ed25519_key.pub | sed 's/^/ /'
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# Alpine's OpenRC sshd init regenerates RSA/ECDSA keys on each start; pin off.
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# No-op on systemd distros.
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sshd_disable_keygen
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# ----------------------------------------------------------------------------
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# 4. Root user keypair
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# ----------------------------------------------------------------------------
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log "Generating Ed25519 keypair for root..."
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mkdir -p /root/.ssh
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chmod 700 /root/.ssh
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touch /root/.ssh/authorized_keys
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chmod 600 /root/.ssh/authorized_keys
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TMP_KEY=$(mktemp -u /tmp/root_ed25519.XXXXXX)
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ssh-keygen -q -t ed25519 -f "$TMP_KEY" -N "" -C "$KEY_COMMENT"
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ROOT_PUB=$(cat "${TMP_KEY}.pub")
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ROOT_PRIV=$(cat "$TMP_KEY")
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# Idempotency: don't add the same pubkey twice.
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grep -qxF "$ROOT_PUB" /root/.ssh/authorized_keys || echo "$ROOT_PUB" >> /root/.ssh/authorized_keys
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# Seed root's authorized_keys with the shared admin keys from globals/ so the
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# box has a known, secure default login (SSH_KEYS_URL first, else
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# globals/authorized_keys). Best-effort: needs the repo's lib.sh present.
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if [[ "${SEED_KEYS:-1}" == "1" && -f "$SCRIPT_DIR/lib.sh" ]]; then
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# shellcheck source=scripts/lib.sh
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. "$SCRIPT_DIR/lib.sh"
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load_globals
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if declare -f resolve_ssh_keys >/dev/null 2>&1; then
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SEEDED=0
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while IFS= read -r k; do
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[[ -n "$k" ]] || continue
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grep -qxF "$k" /root/.ssh/authorized_keys || { echo "$k" >> /root/.ssh/authorized_keys; SEEDED=$((SEEDED+1)); }
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done <<< "$(resolve_ssh_keys 2>/dev/null || true)"
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[[ "$SEEDED" -gt 0 ]] && log "Seeded ${SEEDED} admin key(s) into /root/.ssh/authorized_keys from globals."
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fi
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fi
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# ----------------------------------------------------------------------------
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# 5. sshd_config
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# ----------------------------------------------------------------------------
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log "Writing /etc/ssh/sshd_config..."
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[[ -f /etc/ssh/sshd_config.orig ]] || cp /etc/ssh/sshd_config /etc/ssh/sshd_config.orig
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cat > /etc/ssh/sshd_config <<EOF
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# Generated by harden-ssh.sh on ${OS_ID} -- $(date -u +%FT%TZ)
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# Original config preserved at /etc/ssh/sshd_config.orig
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Port ${SSH_PORT}
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AddressFamily any
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ListenAddress 0.0.0.0
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ListenAddress ::
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PidFile /run/sshd.pid
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# --- Host key: Ed25519 only ---
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HostKey /etc/ssh/ssh_host_ed25519_key
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${KEX_NOTE}
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KexAlgorithms ${KEX_LIST}
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# --- Modern ciphers and MACs ---
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Ciphers chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes128-gcm@openssh.com
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MACs hmac-sha2-512-etm@openssh.com,hmac-sha2-256-etm@openssh.com,umac-128-etm@openssh.com
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# --- Host key signature algorithms ---
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HostKeyAlgorithms ssh-ed25519,ssh-ed25519-cert-v01@openssh.com
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# --- Public key algorithms accepted from clients ---
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# Ed25519 + RSA-4096 (RSA kept for older YubiKey PIV firmware pre-5.7).
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PubkeyAcceptedAlgorithms ssh-ed25519,ssh-ed25519-cert-v01@openssh.com,sk-ssh-ed25519@openssh.com,sk-ssh-ed25519-cert-v01@openssh.com,rsa-sha2-512,rsa-sha2-512-cert-v01@openssh.com,rsa-sha2-256,rsa-sha2-256-cert-v01@openssh.com
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RequiredRSASize 4096
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# --- Authentication ---
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PermitRootLogin prohibit-password
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PubkeyAuthentication yes
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PasswordAuthentication no
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PermitEmptyPasswords no
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ChallengeResponseAuthentication no
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KbdInteractiveAuthentication no
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UsePAM yes
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AuthenticationMethods publickey
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MaxAuthTries 3
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MaxSessions 4
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LoginGraceTime 30s
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# Expose the authenticated key to the session (file at \$SSH_USER_AUTH) so the
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# pam_exec login notifier can report which key was used.
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ExposeAuthInfo yes
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# --- Session restrictions: terminal + SFTP only, no forwarding/tunneling ---
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X11Forwarding no
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X11UseLocalhost yes
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AllowAgentForwarding no
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AllowTcpForwarding no
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AllowStreamLocalForwarding no
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DisableForwarding yes # belt-and-braces: kills *all* forwarding types
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GatewayPorts no
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PermitTunnel no
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PermitUserRC no
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PermitListen none
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PermitOpen none
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PrintMotd no
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TCPKeepAlive no
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ClientAliveInterval 300
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ClientAliveCountMax 2
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# --- Misc ---
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StrictModes yes
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IgnoreRhosts yes
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HostbasedAuthentication no
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Compression no
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Banner none
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# SFTP subsystem: external sftp-server binary (path is per-distro, resolved
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# by oslib's sftp_server_path). Enabled for backup retrieval, with logging to
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# AUTHPRIV at INFO so file transfers are auditable.
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Subsystem sftp ${SFTP_PATH} -f AUTHPRIV -l INFO
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# Restrict who can SSH in. Add other users here if you create them.
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AllowUsers root
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EOF
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# ----------------------------------------------------------------------------
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# 6. Validate config
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# ----------------------------------------------------------------------------
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log "Validating sshd config..."
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if ! sshd -t 2>/tmp/sshd-test.err; then
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cat /tmp/sshd-test.err >&2
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cp /etc/ssh/sshd_config.orig /etc/ssh/sshd_config
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die "sshd config invalid; restored original. NOT reloading."
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fi
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rm -f /tmp/sshd-test.err
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# ----------------------------------------------------------------------------
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# 7. sshguard (brute-force protection)
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# ----------------------------------------------------------------------------
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log "Configuring sshguard (backend + log source are OS-gated in oslib)..."
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mkdir -p /etc/sshguard
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WHITELIST=/etc/sshguard/whitelist
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{
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echo "127.0.0.1"
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echo "::1"
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[[ -n "$ALLOWED_IP" ]] && echo "$ALLOWED_IP"
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} > "$WHITELIST"
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SSHGUARD_BACKEND="$(sshguard_backend)"
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SSHGUARD_LOGREADER="$(sshguard_logreader)"
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[[ -x "${SSHGUARD_BACKEND}" ]] || warn "sshguard backend not found at ${SSHGUARD_BACKEND}; brute-force blocking may be inactive."
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cat > /etc/sshguard/sshguard.conf <<EOF
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BACKEND="${SSHGUARD_BACKEND}"
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${SSHGUARD_LOGREADER:+LOGREADER="${SSHGUARD_LOGREADER}"}
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THRESHOLD=30
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BLOCK_TIME=300
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DETECTION_TIME=1800
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PID_FILE=/run/sshguard.pid
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WHITELIST_FILE=${WHITELIST}
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EOF
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# INPUT -> sshguard jump. When the host firewall (harden-firewall.sh) is enabled
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# it owns the whole INPUT chain -- including this jump -- and persists it via the
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# distro's native iptables package, so we install the firewall and skip the
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# standalone boot hook. Otherwise fall back to the minimal init-agnostic boot
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# hook that just (re)inserts the jump at every boot.
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: "${ENABLE_FIREWALL:=1}"
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# Proxmox (VE/PMG) is Debian underneath, but pve-firewall already owns the host
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# ruleset -- harden-firewall.sh skips those hosts, so fall through to the boot
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# hook and keep sshguard's jump. That jump is safe there: pve-firewall restores
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# with --noflush and only ever flushes its own PVEFW-* chains, and the hook it
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# adds to INPUT is APPENDED -- so a jump inserted with -I sits ahead of it and
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# keeps getting first look at NEW connections, firewall enabled or not.
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# FW_IGNORE_PVE=1 forces our firewall anyway.
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if [[ "$ENABLE_FIREWALL" == "1" && "${FW_IGNORE_PVE:-0}" != "1" ]] && is_proxmox; then
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warn "Proxmox detected -- pve-firewall owns the host firewall; installing only the sshguard jump hook."
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# A host hardened before the skip existed still has a live DROP chain that only
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# accepts the OLD port -- changing SSH_PORT here would lock you out of it.
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[[ -x /usr/local/sbin/firewall-apply || -d /etc/firewall ]] && warn " This host still has an older harden-firewall.sh ruleset. Run 'harden-firewall.sh disable' FIRST, especially if you are changing SSH_PORT."
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ENABLE_FIREWALL=0
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fi
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if [[ "$ENABLE_FIREWALL" == "1" && -f "$SCRIPT_DIR/harden-firewall.sh" ]]; then
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log "Installing host firewall (deny-by-default INPUT; carries the sshguard jump)..."
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SSH_PORT="$SSH_PORT" OPEN_PORTS="${OPEN_PORTS:-}" \
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FW_SSH_SOURCE="${FW_SSH_SOURCE:-}" FW_ALLOW_PING="${FW_ALLOW_PING:-1}" \
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FORCE=1 bash "$SCRIPT_DIR/harden-firewall.sh" apply \
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|| warn "harden-firewall.sh failed; INPUT left unfiltered. Re-run it manually."
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else
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HOOK=$(mktemp)
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cat > "$HOOK" <<'EOF'
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#!/bin/sh
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# Ensure sshguard chain exists and INPUT jumps to it for the SSH port.
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SSH_PORT=$(awk '/^Port / {print $2; exit}' /etc/ssh/sshd_config)
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SSH_PORT=${SSH_PORT:-22}
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for ipt in iptables ip6tables; do
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command -v "$ipt" >/dev/null 2>&1 || continue
|
|
$ipt -N sshguard 2>/dev/null || true
|
|
$ipt -C INPUT -p tcp --dport "$SSH_PORT" -j sshguard 2>/dev/null \
|
|
|| $ipt -I INPUT -p tcp --dport "$SSH_PORT" -j sshguard
|
|
done
|
|
EOF
|
|
install_boot_hook sshguard-iptables "$HOOK"
|
|
rm -f "$HOOK"
|
|
fi
|
|
|
|
svc_enable_start sshguard || warn "Could not start sshguard; check 'sshguard.conf' on this distro."
|
|
|
|
# ----------------------------------------------------------------------------
|
|
# 7b. Optional: SSH login notifier (pam_exec -> ntfy)
|
|
# ----------------------------------------------------------------------------
|
|
# Enabled when NTFY_URL is provided. Reports user + source IP + the key used,
|
|
# filtered by NOTIFY_GROUPS (empty here = every login on this host).
|
|
if [[ -n "${NTFY_URL:-}" ]]; then
|
|
: "${NTFY_REGION:=$(host_region)}"
|
|
log "Installing SSH login notifier (ntfy)..."
|
|
install_login_notifier "$SCRIPT_DIR/ntfy-ssh-login.sh" || warn "Notifier install had issues."
|
|
fi
|
|
|
|
# ----------------------------------------------------------------------------
|
|
# 7c. Optional: daily unattended updates (set AUTO_UPDATE=1). New OS branches
|
|
# are reported, not auto-applied.
|
|
# ----------------------------------------------------------------------------
|
|
if [[ "${AUTO_UPDATE:-0}" == "1" && -f "$SCRIPT_DIR/auto-update.sh" ]]; then
|
|
log "Scheduling daily auto-update..."
|
|
AUTO_REBOOT="${AUTO_REBOOT:-0}" \
|
|
ALLOW_RELEASE_UPGRADE="${ALLOW_RELEASE_UPGRADE:-0}" \
|
|
NOTIFY="${NOTIFY:-1}" \
|
|
bash "$SCRIPT_DIR/auto-update.sh" install || warn "Could not schedule auto-update."
|
|
fi
|
|
|
|
# ----------------------------------------------------------------------------
|
|
# 8. Enable sshd & reload (with safety prompt)
|
|
# ----------------------------------------------------------------------------
|
|
SSHD_SVC="$(sshd_service)"
|
|
log "Enabling ${SSHD_SVC} at boot..."
|
|
svc_enable "$SSHD_SVC"
|
|
|
|
# Print the private key BEFORE reloading sshd so a bad reload still leaves you
|
|
# with what you need to get back in via console.
|
|
cat <<EOF
|
|
|
|
================================================================
|
|
COPY THIS PRIVATE KEY TO YOUR CLIENT *NOW*
|
|
|
|
Save it as e.g. ~/.ssh/id_ed25519_host on your local machine,
|
|
chmod 600, and connect with:
|
|
|
|
ssh -i ~/.ssh/id_ed25519_host -p ${SSH_PORT} root@<host>
|
|
|
|
----- BEGIN ROOT PRIVATE KEY (Ed25519) -----
|
|
${ROOT_PRIV}
|
|
----- END ROOT PRIVATE KEY -----
|
|
|
|
Public key (already in /root/.ssh/authorized_keys):
|
|
${ROOT_PUB}
|
|
|
|
Host fingerprint (verify on first connect):
|
|
$(ssh-keygen -l -f /etc/ssh/ssh_host_ed25519_key.pub)
|
|
|
|
================================================================
|
|
EOF
|
|
|
|
shred -u "$TMP_KEY" "${TMP_KEY}.pub" 2>/dev/null || rm -f "$TMP_KEY" "${TMP_KEY}.pub"
|
|
|
|
if [[ "$FORCE" != "1" ]]; then
|
|
cat <<EOF
|
|
sshd config has passed validation. Ready to reload sshd.
|
|
|
|
If you are connected via SSH RIGHT NOW, open a SECOND session in another
|
|
terminal -- before answering yes -- to verify the new keys, port, and PQ
|
|
KEX work. If something is wrong, this reload will end your current session.
|
|
|
|
Test in another terminal first:
|
|
ssh -i ~/.ssh/<your saved key> -p ${SSH_PORT} root@<host>
|
|
|
|
Reload sshd now? [y/N]
|
|
EOF
|
|
read -r ans
|
|
if [[ "${ans,,}" != "y" && "${ans,,}" != "yes" ]]; then
|
|
warn "Skipping reload. Run 'svc reload of ${SSHD_SVC}' manually when ready."
|
|
exit 0
|
|
fi
|
|
fi
|
|
|
|
log "Reloading ${SSHD_SVC}..."
|
|
# Reload -- and on Alpine swap in the PAM sshd build if the running one
|
|
# predates this config (oslib explains why that can happen).
|
|
sshd_apply_config
|
|
log "Done. Your session, if any, should remain alive (reload preserves connections)."
|
|
log "Test from another machine before closing this session."
|