Not implemented: compression open flags other than FastLZ, CBT / allocated-block queries, disk geometry (DDB_GET), encrypted disks, and direct ESXi ha-nfc without vCenter vpxa-nfc.

Install

python3.12 -m venv .venv
.venv/bin/pip install -e .

Usage

from openvixdisklib import nfc_auth
from openvixdisklib import openvixdisklib as vixdisklib

handle = vixdisklib.VixDiskLibHandle(
    vixdisklib_compatibility_version="8.0")
buf = vixdisklib.get_buffer(vixdisklib.VIXDISKLIB_SECTOR_SIZE)
thumbprint = nfc_auth.get_ssl_cert_thumbprint("vcenter.example.com")

with handle.connect(
        server_name="vcenter.example.com",
        thumbprint=thumbprint,
        username="[email protected]",
        password="secret",
        vmx_spec="moref=vm-1234",
        transport_modes="nbdssl",
        read_only=False) as conn:
    with handle.open(conn, "[datastore] vm/vm.vmdk", flags=0) as disk:
        handle.write(disk, 0, 1, buf)
        handle.read(disk, 0, 1, buf)

Lower-level NFC helpers live in openvixdisklib.nfc_auth and openvixdisklib.nfc_open if you need the ticket or socket without the VDDK-shaped handle.

Layout

Path	Role
`openvixdisklib/openvixdisklib.py`	Drop-in handle (`connect` / `open` / `read` / `write`)
`openvixdisklib/nfc_auth.py`	VIM login, NFC ticket, authd on 902
`openvixdisklib/nfc_open.py`	Classic NFC handshake, AIO open, sector read/write
`openvixdisklib/fastlz.py`	FastLZ NFC adapter (pip `pyfastlz`)
`tests/integration/`	Live pytest suite against a lab vCenter
`tests/perf/`	Throughput comparison of openvixdisklib vs VDDK
`tests/integration/vixdisklib.py`	Native VDDK wrapper used only to cross-check
`docs/`	Protocol notes and reverse-engineering steps

VDDK shared libraries, if present for cross-check, belong in .vddk/ (gitignored). They are not required to use openvixdisklib.

Tests

Lab connection settings live in .test_config.yaml at the repo root (gitignored). Copy:

host: vcenter.example.com
port: 443
username: [email protected]
password: secret
allow_untrusted: true
datacenter: Datacenter
datastore: datastore0

A session-scoped pytest fixture creates an empty VM with a 10 GiB thin disk on that datastore and tears it down when the session ends. Tests write known patterns and read them back.

tox -e integration
# or
.venv/bin/pytest tests/integration

Compare write/read throughput of openvixdisklib and native VDDK (64KiB, 129-sector, and 32MiB transfers; nbdssl and nbd; plain and FastLZ):

tox -e perf

VDDK cross-check tests skip when libvixDiskLib is not loadable from .vddk. tox -e integration sets LD_LIBRARY_PATH to that directory and clears LD_PRELOAD. For a direct pytest run, do the same.

Lint and typecheck: tox -e pep8, tox -e mypy.

Documentation

Document	Contents
`docs/nfc_auth.md`	Ticket SOAP and authd handshake
`docs/nfc_open.md`	Classic NFC and AIO open
`docs/nfc_read.md`	AIO IO / `VixDiskLib_Read`
`docs/nfc_write.md`	AIO IO / `VixDiskLib_Write`
`docs/ssl_hook.md`	TLS intercept used for capture
`docs/reverse_engineering_procedure.md`	How the protocol was recovered