Adds persistent storage using modernc.org/sqlite (pure Go). Login
attempts are deduplicated by (username, password, ip) with counts.
Sessions and session logs are tracked with UUID IDs. Includes embedded
SQL migrations, configurable retention with background pruning, and
an in-memory store for tests.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Add log_format config field ("text" default, "json" for structured
JSON output) to support machine-readable logging.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
- Use subtle.ConstantTimeCompare for static credential checks to
prevent timing side-channel attacks
- Cap failCounts (100k) and rememberedCreds (10k) maps with eviction
to prevent memory exhaustion from botnet-scale scanning
- Sweep expired credentials on each auth attempt
- Add configurable max_connections (default 500) with semaphore to
limit concurrent connections and prevent goroutine/fd exhaustion
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Add core SSH server with password authentication, per-IP failure
tracking, credential memory with TTL, and static credential support.
Includes TOML config loading with validation, Ed25519 host key
auto-generation, and a Nix package output.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
