net.core.rmem_default is a global (non-namespaced) kernel sysctl.
Docker's OCI runtime rejects it at container start with "permission denied"
unless the container runs --privileged. Drop it from the windows profile;
TTL=128 and tcp_syn_retries=2 are sufficient for nmap TTL-based detection.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Each decky base container now receives a set of Linux kernel sysctls
(net.ipv4.ip_default_ttl, net.ipv4.tcp_syn_retries, etc.) tuned to
match the claimed OS family, making nmap OS detection return the
expected OS rather than the Linux host.
- decnet/os_fingerprint.py: OS profile table (linux/windows/bsd/embedded/cisco)
keyed by TTL and TCP tuning knobs
- decnet/archetypes.py: Archetype gains nmap_os field; windows-* → "windows",
printer/iot/industrial → "embedded", rest → "linux"
- decnet/config.py: DeckyConfig gains nmap_os field (default "linux")
- decnet/cli.py: nmap_os resolved from archetype → DeckyConfig in both CLI
and INI build paths
- decnet/composer.py: base container gets sysctls + cap_add: [NET_ADMIN];
service containers inherit via shared network namespace
- tests/test_os_fingerprint.py: 48 new tests covering profiles, compose
injection, archetype coverage, and CLI propagation
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
