The 5 management tools (get_service_status, tail_log, list_lxcs,
get_lxc_state, ping_service) were registered with sse but all SSH calls
went to per-host targets via a 'mcp-reader' user that didn't exist
anywhere. New design routes every management call through ONE channel:
LXC 105 -> hubris (SSH key + restricted authorized_keys command), then
hubris pct-execs into the right LXC where needed.
Adds mcp/mcp-reader-shell — a strict allowlist wrapper read from
$SSH_ORIGINAL_COMMAND. Rejects shell metacharacters up front and then
matches against a fixed set of read-only patterns (systemctl is-active/
is-enabled, journalctl -u, pct list/status/config, pct exec for the
same subset). Logged to syslog tag mcp-reader.
Authorized_keys line on hubris:
command="/usr/local/bin/mcp-reader-shell",restrict ssh-ed25519 ... mcp-reader@homelab-mcp
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
