Files
diskless-workstation/files/dracut/95dot1x-macsec/tpm-enrol.sh
T
Audiobuzz 86a9839cc4 fleet-enrol: content-aware NV check (-check-only), not blind "index defined"
The enrol trigger keyed on "is NV 0x01800001 defined/readable", so leftover
state (an earlier tpm-provision run — bench-seen on the 820: "cert present —
normal boot" with no real identity) or random bytes (tpm-selftest) silently
suppressed enrolment. Now content-aware:

- tpmkey.ReadNVCert reads the full NV contents (chunked).
- classifyNVCert (TPM-agnostic, unit-tested): parses X.509, checks validity
  window, and when a real fleet CA bundle is present verifies the cert chains
  to it. Only a valid fleet cert = enrolled.
- New `fleet-enrol -check-only` (no network/no key-gen) exits 0=valid cert,
  20=enrol needed, 1=error. The full enrol path uses the same classification
  instead of NVPresent.
- The dracut hook calls -check-only as the single gate, replacing the blind
  tpm2_nvread (and its now-dead TPM2TOOLS_TCTI export). tpm2_nvread stays in
  the initramfs for the secure path (dot1x-macsec-up.sh).

Lab fallback: the shipped radius-ca.pem is a placeholder (not a cert) ->
loadCAPool returns nil -> chain-less "parseable + unexpired" acceptance, so
reboot-converge doesn't loop; production replaces radius-ca.pem with the real
fleet CA for strict chaining.

Tests: classifyNVCert table (valid/expired/garbage/foreign/no-CA) + simtest
ReadNVCert roundtrip across the 512B chunk. All pass; packer validate clean.
2026-07-03 01:02:25 +00:00

131 lines
6.3 KiB
Bash

#!/bin/bash
# tpm-enrol.sh — initqueue/settled hook, runs BEFORE dot1x-macsec-up.sh.
#
# INLINE empty-NV enrolment GATE (docs/tpm-enrolment-design.md). On a secure
# build whose TPM NV 0x01800001 is empty, it brings up a pre-auth network on the
# physical NIC and hands off to the out-of-VM `fleet-enrol` binary (Go + go-tpm),
# which generates the key/CSR, talks to the broker, shows the Plymouth
# fingerprint, and writes the issued cert to NV. On success this hook REBOOTS.
# It is a no-op when a cert is already present (normal boot — dot1x-macsec-up.sh
# reads NV) or when disabled via rd.fleet.enrol=0.
#
# The crypto/HTTP/NV work lives in the binary (testable, TPM-direct); this hook
# owns only the boot-environment concerns: the empty-NV gate, networking, and the
# reboot-to-converge. Empty-NV and the secure path are mutually exclusive, so this
# never reorders the load-bearing boot sequence (invariant #2).
#
# TEST-MODE ENROLMENT (rd.dot1x=0): enrolment ALSO runs on the open/test path so
# the flow can be exercised on a host with a TPM + a reachable broker WITHOUT
# standing up 802.1X/MACsec/RADIUS. In test mode `ip=dhcp` already owns the NIC,
# so this hook must NOT re-DHCP it (that races dracut → "address already
# assigned"); it just uses the existing lease. Production still gates real
# enrolment to the secure path; use rd.fleet.enrol=0 to disable it in either mode.
type getarg >/dev/null 2>&1 || . /lib/dracut-lib.sh
STAMP=/run/dot1x/.enrol-done
[ -e "$STAMP" ] && exit 0
mkdir -p /run/dot1x
# --- skip conditions --------------------------------------------------------
if [ "$(getarg rd.fleet.enrol=)" = "0" ]; then
info "tpm-enrol: disabled by rd.fleet.enrol=0"; exit 0
fi
# Test mode (rd.dot1x=0): enrolment still runs, but ip=dhcp owns the NIC, so we
# must not reconfigure it below.
TESTMODE=0
[ "$(getarg rd.dot1x=)" = "0" ] && TESTMODE=1
# --- knobs (override on the kernel cmdline) ---------------------------------
NVINDEX=$(getarg rd.dot1x.nvindex=); [ -n "$NVINDEX" ] || NVINDEX=0x01800001
# Persistent handle for the signing key: a NON-reserved owner handle. NOT the EK
# slot 0x81010001 (which most firmware/swtpm provisioning already occupies) nor
# the SRK 0x81000001 — see EnsureKey / CLAUDE.md invariant #1.
HANDLE=$(getarg rd.dot1x.handle=); [ -n "$HANDLE" ] || HANDLE=0x81000100
ENROL_URL=$(getarg rd.fleet.enrol_url=); [ -n "$ENROL_URL" ] || ENROL_URL=http://boot.fleet.lab/enrol
NETTMO=$(getarg rd.dot1x.timeout=); [ -n "$NETTMO" ] || NETTMO=60
# Wait briefly for the TPM resource-manager device so an early settle (before the
# TPM driver is up) doesn't misread NV as empty and wrongly trigger enrolment.
i=0
while [ ! -e /dev/tpmrm0 ] && [ "$i" -lt 10 ]; do sleep 1; i=$((i + 1)); done
[ -e /dev/tpmrm0 ] || { warn "tpm-enrol: no TPM (/dev/tpmrm0) — leaving to the secure path"; exit 0; }
# --- already enrolled? then this is a normal boot — do NOT touch the network -
# (Bringing up en* here would fight the secure path, which needs it UNMANAGED for
# wpa_supplicant. So gate on NV BEFORE any network action.)
# CONTENT-AWARE gate (fleet-enrol -check-only, no network/no key-gen): reads NV,
# parses the cert, and — when the fleet CA is bundled — verifies it chains, so a
# leftover/foreign/expired cert (or garbage) does NOT masquerade as enrolled.
# rc: 0 = valid fleet cert (normal boot); 20 = enrolment needed; other = error.
/usr/sbin/fleet-enrol -check-only -nvindex "$NVINDEX" -handle "$HANDLE"
rc=$?
case "$rc" in
0) info "tpm-enrol: valid fleet cert at NV $NVINDEX — normal boot"; exit 0 ;;
20) : ;; # fall through to enrolment
*) warn "tpm-enrol: NV check failed (rc=$rc) — leaving to the secure path"; exit 0 ;;
esac
# Committed to enrolling — one attempt per boot.
: > "$STAMP"
warn "tpm-enrol: no valid fleet cert in NV $NVINDEX — starting FIRST-TIME TPM enrolment"
# NIC: explicit rd.dot1x.if=, else first non-loopback, non-macsec interface.
NIC=$(getarg rd.dot1x.if=)
if [ -z "$NIC" ]; then
for _dev in /sys/class/net/*; do
_name=${_dev##*/}
case "$_name" in lo|macsec*) continue ;; esac
NIC=$_name; break
done
fi
[ -n "$NIC" ] || { warn "tpm-enrol: no network interface found"; exit 1; }
# --- network on the PHYSICAL NIC --------------------------------------------
if [ "$TESTMODE" = "1" ]; then
# Test mode: ip=dhcp already brought the NIC up + wrote resolv.conf. Do NOT
# reconfigure it (a second config races dracut → "address already assigned").
info "tpm-enrol: test mode (rd.dot1x=0) — using the ip=dhcp NIC as-is"
ip link set "$NIC" up 2>/dev/null || true
else
# Secure mode: nm-unmanaged.sh leaves en* UNMANAGED (wpa_supplicant would own
# it), but there is no supplicant yet — so explicitly hand the NIC to NM for a
# plaintext pre-auth DHCP lease (same permit-set the firmware used for the UKI).
# The runtime `nmcli device set managed yes` overrides the unmanaged drop-in.
ip link set "$NIC" up 2>/dev/null || true
nmcli device set "$NIC" managed yes 2>/dev/null || true
nmcli -w 0 device connect "$NIC" 2>/dev/null || true
fi
i=0
while [ "$i" -lt "$NETTMO" ]; do
ip -4 addr show "$NIC" 2>/dev/null | grep -q 'inet ' && break
sleep 1; i=$((i + 1))
done
if [ "$i" -ge "$NETTMO" ]; then
warn "tpm-enrol: no pre-auth DHCP lease on $NIC after ${NETTMO}s"
plymouth message --text="TPM enrolment FAILED (no network)" 2>/dev/null || true
exit 1
fi
info "tpm-enrol: pre-auth lease on $NIC; handing off to fleet-enrol ($ENROL_URL)"
# --- hand off to the enrolment binary ---------------------------------------
# It drives the TPM (key/CSR/NV), the broker exchange, and the Plymouth
# fingerprint. Exit 0 = enrolled (reboot to converge); 10 = already enrolled
# (shouldn't reach here after the NV gate, but treat as normal boot); else fail.
/usr/sbin/fleet-enrol -url "$ENROL_URL" -iface "$NIC" -nvindex "$NVINDEX" -handle "$HANDLE"
rc=$?
case "$rc" in
0)
info "tpm-enrol: enrolled — rebooting into the secure path"
sleep 2
systemctl --no-block reboot 2>/dev/null || reboot -f 2>/dev/null || \
{ echo 1 > /proc/sys/kernel/sysrq 2>/dev/null; echo b > /proc/sysrq-trigger 2>/dev/null; }
exit 0 ;;
10)
info "tpm-enrol: fleet-enrol reports cert already present — normal boot"
exit 0 ;;
*)
warn "tpm-enrol: fleet-enrol failed (rc=$rc) — reboot to retry"
exit 1 ;;
esac