refactor: prober auto-discovers attackers from log stream

Remove --probe-targets from deploy. The prober now tails the JSON log
file and automatically discovers attacker IPs, JARM-probing each on
common C2 ports (443, 8443, 8080, 4443, 50050, etc.).

- Deploy spawns prober automatically (like collector), no manual targets
- `decnet probe` runs in foreground, --daemon detaches to background
- Worker tracks probed (ip, port) pairs to avoid redundant scans
- Empty JARM hashes (no TLS server) are silently skipped
- 80 prober tests (jarm + worker discovery + bounty extraction)

tests/test_prober_worker.py

@@ -0,0 +1,207 @@
+"""
+Tests for the prober worker — target discovery from the log stream and
+probe cycle behavior.
+"""
+
+from __future__ import annotations
+
+import json
+from pathlib import Path
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+from decnet.prober.jarm import JARM_EMPTY_HASH
+from decnet.prober.worker import (
+    DEFAULT_PROBE_PORTS,
+    _discover_attackers,
+    _probe_cycle,
+    _write_event,
+)
+
+
+# ─── _discover_attackers ─────────────────────────────────────────────────────
+
+class TestDiscoverAttackers:
+
+    def test_discovers_unique_ips(self, tmp_path: Path):
+        json_file = tmp_path / "decnet.json"
+        records = [
+            {"service": "sniffer", "event_type": "tls_client_hello", "attacker_ip": "10.0.0.1", "fields": {}},
+            {"service": "ssh", "event_type": "login_attempt", "attacker_ip": "10.0.0.2", "fields": {}},
+            {"service": "sniffer", "event_type": "tls_client_hello", "attacker_ip": "10.0.0.1", "fields": {}},  # dup
+        ]
+        json_file.write_text("\n".join(json.dumps(r) for r in records) + "\n")
+
+        ips, pos = _discover_attackers(json_file, 0)
+        assert ips == {"10.0.0.1", "10.0.0.2"}
+        assert pos > 0
+
+    def test_skips_prober_events(self, tmp_path: Path):
+        json_file = tmp_path / "decnet.json"
+        records = [
+            {"service": "prober", "event_type": "jarm_fingerprint", "attacker_ip": "10.0.0.99", "fields": {}},
+            {"service": "ssh", "event_type": "login_attempt", "attacker_ip": "10.0.0.1", "fields": {}},
+        ]
+        json_file.write_text("\n".join(json.dumps(r) for r in records) + "\n")
+
+        ips, _ = _discover_attackers(json_file, 0)
+        assert "10.0.0.99" not in ips
+        assert "10.0.0.1" in ips
+
+    def test_skips_unknown_ips(self, tmp_path: Path):
+        json_file = tmp_path / "decnet.json"
+        records = [
+            {"service": "sniffer", "event_type": "startup", "attacker_ip": "Unknown", "fields": {}},
+        ]
+        json_file.write_text("\n".join(json.dumps(r) for r in records) + "\n")
+
+        ips, _ = _discover_attackers(json_file, 0)
+        assert len(ips) == 0
+
+    def test_handles_missing_file(self, tmp_path: Path):
+        json_file = tmp_path / "nonexistent.json"
+        ips, pos = _discover_attackers(json_file, 0)
+        assert len(ips) == 0
+        assert pos == 0
+
+    def test_resumes_from_position(self, tmp_path: Path):
+        json_file = tmp_path / "decnet.json"
+        line1 = json.dumps({"service": "ssh", "attacker_ip": "10.0.0.1", "fields": {}}) + "\n"
+        json_file.write_text(line1)
+
+        _, pos1 = _discover_attackers(json_file, 0)
+
+        # Append more
+        with open(json_file, "a") as f:
+            f.write(json.dumps({"service": "ssh", "attacker_ip": "10.0.0.2", "fields": {}}) + "\n")
+
+        ips, pos2 = _discover_attackers(json_file, pos1)
+        assert ips == {"10.0.0.2"}  # only the new one
+        assert pos2 > pos1
+
+    def test_handles_file_rotation(self, tmp_path: Path):
+        json_file = tmp_path / "decnet.json"
+        # Write enough data to push position well ahead
+        lines = [json.dumps({"service": "ssh", "attacker_ip": f"10.0.0.{i}", "fields": {}}) + "\n" for i in range(10)]
+        json_file.write_text("".join(lines))
+        _, pos = _discover_attackers(json_file, 0)
+        assert pos > 0
+
+        # Simulate rotation — new file is smaller than the old position
+        json_file.write_text(json.dumps({"service": "ssh", "attacker_ip": "10.0.0.99", "fields": {}}) + "\n")
+        assert json_file.stat().st_size < pos
+
+        ips, new_pos = _discover_attackers(json_file, pos)
+        assert "10.0.0.99" in ips
+
+    def test_handles_malformed_json(self, tmp_path: Path):
+        json_file = tmp_path / "decnet.json"
+        json_file.write_text("not valid json\n" + json.dumps({"service": "ssh", "attacker_ip": "10.0.0.1", "fields": {}}) + "\n")
+
+        ips, _ = _discover_attackers(json_file, 0)
+        assert "10.0.0.1" in ips
+
+
+# ─── _probe_cycle ────────────────────────────────────────────────────────────
+
+class TestProbeCycle:
+
+    @patch("decnet.prober.worker.jarm_hash")
+    def test_probes_new_ips(self, mock_jarm: MagicMock, tmp_path: Path):
+        mock_jarm.return_value = "c0c" * 10 + "a" * 32  # fake 62-char hash
+        log_path = tmp_path / "decnet.log"
+        json_path = tmp_path / "decnet.json"
+
+        targets = {"10.0.0.1"}
+        probed: dict[str, set[int]] = {}
+
+        _probe_cycle(targets, probed, [443, 8443], log_path, json_path, timeout=1.0)
+
+        assert mock_jarm.call_count == 2  # two ports
+        assert 443 in probed["10.0.0.1"]
+        assert 8443 in probed["10.0.0.1"]
+
+    @patch("decnet.prober.worker.jarm_hash")
+    def test_skips_already_probed_ports(self, mock_jarm: MagicMock, tmp_path: Path):
+        mock_jarm.return_value = "c0c" * 10 + "a" * 32
+        log_path = tmp_path / "decnet.log"
+        json_path = tmp_path / "decnet.json"
+
+        targets = {"10.0.0.1"}
+        probed: dict[str, set[int]] = {"10.0.0.1": {443}}
+
+        _probe_cycle(targets, probed, [443, 8443], log_path, json_path, timeout=1.0)
+
+        # Should only probe 8443 (443 already done)
+        assert mock_jarm.call_count == 1
+        mock_jarm.assert_called_once_with("10.0.0.1", 8443, timeout=1.0)
+
+    @patch("decnet.prober.worker.jarm_hash")
+    def test_empty_hash_not_logged(self, mock_jarm: MagicMock, tmp_path: Path):
+        """All-zeros JARM hash (no TLS server) should not be written as a jarm_fingerprint event."""
+        mock_jarm.return_value = JARM_EMPTY_HASH
+        log_path = tmp_path / "decnet.log"
+        json_path = tmp_path / "decnet.json"
+
+        targets = {"10.0.0.1"}
+        probed: dict[str, set[int]] = {}
+
+        _probe_cycle(targets, probed, [443], log_path, json_path, timeout=1.0)
+
+        # Port should be marked as probed
+        assert 443 in probed["10.0.0.1"]
+        # But no jarm_fingerprint event should be written
+        if json_path.exists():
+            content = json_path.read_text()
+            assert "jarm_fingerprint" not in content
+
+    @patch("decnet.prober.worker.jarm_hash")
+    def test_exception_marks_port_probed(self, mock_jarm: MagicMock, tmp_path: Path):
+        mock_jarm.side_effect = OSError("Connection refused")
+        log_path = tmp_path / "decnet.log"
+        json_path = tmp_path / "decnet.json"
+
+        targets = {"10.0.0.1"}
+        probed: dict[str, set[int]] = {}
+
+        _probe_cycle(targets, probed, [443], log_path, json_path, timeout=1.0)
+
+        # Port marked as probed to avoid infinite retries
+        assert 443 in probed["10.0.0.1"]
+
+    @patch("decnet.prober.worker.jarm_hash")
+    def test_skips_ip_with_all_ports_done(self, mock_jarm: MagicMock, tmp_path: Path):
+        log_path = tmp_path / "decnet.log"
+        json_path = tmp_path / "decnet.json"
+
+        targets = {"10.0.0.1"}
+        probed: dict[str, set[int]] = {"10.0.0.1": {443, 8443}}
+
+        _probe_cycle(targets, probed, [443, 8443], log_path, json_path, timeout=1.0)
+
+        assert mock_jarm.call_count == 0
+
+
+# ─── _write_event ────────────────────────────────────────────────────────────
+
+class TestWriteEvent:
+
+    def test_writes_rfc5424_and_json(self, tmp_path: Path):
+        log_path = tmp_path / "decnet.log"
+        json_path = tmp_path / "decnet.json"
+
+        _write_event(log_path, json_path, "test_event", target_ip="10.0.0.1", msg="test")
+
+        assert log_path.exists()
+        assert json_path.exists()
+
+        log_content = log_path.read_text()
+        assert "test_event" in log_content
+        assert "decnet@55555" in log_content
+
+        json_content = json_path.read_text()
+        record = json.loads(json_content.strip())
+        assert record["event_type"] == "test_event"
+        assert record["service"] == "prober"
+        assert record["fields"]["target_ip"] == "10.0.0.1"