feat: FreeBSD and OpenBSD drivers, read side

FreeBSDDriver (`freebsd`) and OpenBSDDriver (`openbsd`) on a shared
BsdDriver, for the BSD VMs netOrk provisions and BSD hosts added by hand
(NetOrk/netork#798).

- SSH over exec channels (napalm-device-types' run_on_transport): no PTY,
  stdout and stderr apart, real exit codes; run_command()/open_stream()
  are public. Root through `sudo -S` with the password on stdin, or
  `sudo -n` without one.
- Facts: hostname, release and running kernel (freebsd-version / uname),
  hardware from SMBIOS (kenv) or hw.* sysctls, uptime from kern.boottime.
- Interfaces and addresses (ifconfig -a: ether/lladdr, hex netmasks,
  scoped IPv6), routes (netstat -rn, OpenBSD's abbreviated networks
  written out, host/broadcast/loopback entries left out), ARP (FreeBSD's
  sentences, OpenBSD's table), users and groups, processes (lstart read as
  one five-word field), cron jobs (system crontab and the login user's).
- Parsers are pure functions, tested on output recorded from FreeBSD 15.1
  (hand-installed and cloud image) and OpenBSD 7.9 (NetOrk/netork#793),
  with internal addresses replaced by documentation ranges.

tests/test_drivers.py

@@ -0,0 +1,195 @@
+"""FreeBSDDriver and OpenBSDDriver: what netOrk's poll reads, on recorded output."""
+
+from __future__ import annotations
+
+from pathlib import Path
+
+import pytest
+from napalm.base import NetworkDriver
+from napalm_device_types import OSDriver
+
+from napalm_bsd import FreeBSDDriver, OpenBSDDriver
+from napalm_bsd.base import BsdDriver
+
+FIXTURES = Path(__file__).parent / "fixtures"
+PS = "ps_axww_o_user_pid_ppid_cpu_mem_vsz_rss_stat_lstart_command.txt"
+
+
+def _read(system: str, name: str) -> str:
+    return (FIXTURES / system / name).read_text()
+
+
+def _driver(cls, answers: dict[str, str]):
+    """A driver whose commands are answered from *answers*; unknown ones print nothing."""
+    driver = cls("host", "netork", "")
+    asked: list[str] = []
+
+    def out(command: str, *, privileged: bool = False, timeout: float = 60) -> str:
+        asked.append(command)
+        return answers.get(command, "").strip()
+
+    driver._out = out  # type: ignore[method-assign]
+    driver.asked = asked  # type: ignore[attr-defined]
+    return driver
+
+
+def _freebsd_host():
+    s = "freebsd-host"
+    return _driver(
+        FreeBSDDriver,
+        {
+            "sysctl -n kern.hostname": "bsd-01.lab.example",
+            "freebsd-version -u": "15.1-RELEASE",
+            "freebsd-version -r": "15.1-RELEASE",
+            FreeBSDDriver.PLATFORM_COMMAND: "maker=QEMU\nproduct=Standard PC (i440FX + PIIX, 1996)\nserial=",
+            "sysctl -n kern.boottime": _read(s, "sysctl_n_kern.boottime.txt"),
+            "date +%s": "1791408816",
+            "ifconfig -a": _read(s, "ifconfig_a.txt"),
+            "netstat -rnW": _read(s, "netstat_rn.txt"),
+            "arp -an": _read(s, "arp_an.txt"),
+            "cat /etc/passwd": _read(s, "cat_etc_passwd.txt"),
+            "cat /etc/group": _read(s, "cat_etc_group.txt"),
+            BsdDriver.PS_COMMAND: _read(s, PS),
+            "cat /etc/crontab": _read(s, "cat_etc_crontab.txt"),
+            "crontab -l": "0 4 * * * /home/netork/backup.sh\n",
+        },
+    )
+
+
+def _openbsd_vm():
+    s = "openbsd-vm"
+    return _driver(
+        OpenBSDDriver,
+        {
+            "hostname": "spike-openbsd",
+            "uname -sr": "OpenBSD 7.9",
+            "uname -v": "GENERIC.MP#449",
+            OpenBSDDriver.PLATFORM_COMMAND: "vendor=QEMU\nproduct=Standard PC (i440FX + PIIX, 1996)\nserialno=",
+            "sysctl -n kern.boottime": _read(s, "sysctl_n_kern.boottime.txt"),
+            "date +%s": "1791406889",
+            "ifconfig -a": _read(s, "ifconfig_a.txt"),
+            "netstat -rn": _read(s, "netstat_rn.txt"),
+            "arp -an": _read(s, "arp_an.txt"),
+            "cat /etc/passwd": _read(s, "cat_etc_passwd.txt"),
+            BsdDriver.PS_COMMAND: _read(s, PS),
+        },
+    )
+
+
+class TestIdentity:
+    @pytest.mark.parametrize(
+        ("cls", "name", "label"),
+        [(FreeBSDDriver, "freebsd", "FreeBSD"), (OpenBSDDriver, "openbsd", "OpenBSD")],
+    )
+    def test_names(self, cls, name, label):
+        assert cls.DRIVER_NAME == name
+        assert cls.TYPE_LABEL == label
+        assert issubclass(cls, OSDriver)
+
+    @pytest.mark.parametrize("cls", [FreeBSDDriver, OpenBSDDriver])
+    @pytest.mark.parametrize(
+        "getter",
+        [
+            "get_facts",
+            "get_interfaces",
+            "get_interfaces_ip",
+            "get_route_to",
+            "get_arp_table",
+            "get_lldp_neighbors",
+            "get_users",
+            "get_processes",
+            "get_cron_jobs",
+        ],
+    )
+    def test_implements_what_the_poll_reads(self, cls, getter):
+        """netOrk asks whether a getter is overridden, not merely present."""
+        assert getattr(cls, getter) is not getattr(NetworkDriver, getter, None)
+
+
+class TestFacts:
+    def test_freebsd(self):
+        facts = _freebsd_host().get_facts()
+        assert facts == {
+            "hostname": "bsd-01",
+            "fqdn": "bsd-01.lab.example",
+            "vendor": "QEMU",
+            "model": "Standard PC (i440FX + PIIX, 1996)",
+            "serial_number": "",
+            "os_version": "FreeBSD 15.1-RELEASE",
+            "uptime": 1791408816 - 1791405216,
+            "interface_list": ["em0"],
+            "running_kernel": "15.1-RELEASE",
+        }
+
+    def test_openbsd(self):
+        facts = _openbsd_vm().get_facts()
+        assert facts["hostname"] == facts["fqdn"] == "spike-openbsd"
+        assert facts["os_version"] == "OpenBSD 7.9"
+        assert facts["running_kernel"] == "GENERIC.MP#449"
+        assert facts["uptime"] == 100
+        assert facts["interface_list"] == ["vio0", "enc0", "pflog0"]
+
+    def test_an_unreadable_boottime_is_no_uptime(self):
+        driver = _freebsd_host()
+        driver._out = lambda command, **kw: ""  # type: ignore[method-assign]
+        assert driver.get_facts()["uptime"] == -1
+
+
+class TestInterfaces:
+    def test_napalm_shape(self):
+        interfaces = _freebsd_host().get_interfaces()
+        assert interfaces["em0"] == {
+            "is_up": True,
+            "is_enabled": True,
+            "description": "",
+            "last_flapped": -1.0,
+            "speed": 1000.0,
+            "mtu": 1500,
+            "mac_address": "bc:24:11:20:b0:20",
+        }
+
+    def test_addresses(self):
+        assert _openbsd_vm().get_interfaces_ip()["vio0"] == {
+            "ipv4": {"10.0.2.15": {"prefix_length": 24}},
+            "ipv6": {},
+        }
+
+
+class TestRoutesAndNeighbours:
+    def test_routes_keyed_by_network(self):
+        routes = _freebsd_host().get_route_to()
+        default = routes["0.0.0.0/0"][0]
+        assert default["next_hop"] == "192.0.2.1"
+        assert default["outgoing_interface"] == "em0"
+        assert default["protocol"] == "static"
+        assert default["current_active"] is True
+
+    def test_openbsd_reads_routes_without_W(self):
+        driver = _openbsd_vm()
+        assert "10.0.2.0/24" in driver.get_route_to()
+        assert "netstat -rn" in driver.asked
+
+    def test_arp(self):
+        assert _openbsd_vm().get_arp_table()[0]["ip"] == "10.0.2.2"
+
+    def test_no_lldp_daemon_means_no_neighbours(self):
+        assert _freebsd_host().get_lldp_neighbors() == {}
+
+
+class TestAccountsAndProcesses:
+    def test_users(self):
+        users = _freebsd_host().get_users()
+        assert next(u for u in users if u["username"] == "root")["groups"] == ["wheel", "operator"]
+
+    def test_processes(self):
+        init = next(p for p in _openbsd_vm().get_processes() if p["pid"] == 1)
+        assert init["command"] == "/sbin/init"
+
+    def test_cron_jobs_from_the_system_and_the_login_users_crontab(self):
+        jobs = _freebsd_host().get_cron_jobs()
+        assert {"user": "root", "schedule": "0 * * * *", "command": "newsyslog"} in jobs
+        assert {
+            "user": "netork",
+            "schedule": "0 4 * * *",
+            "command": "/home/netork/backup.sh",
+        } in jobs