ca2749e1bd
In practical terms, passt doesn't benefit from the additional protection offered by the AGPL over the GPL, because it's not suitable to be executed over a computer network. Further, restricting the distribution under the version 3 of the GPL wouldn't provide any practical advantage either, as long as the passt codebase is concerned, and might cause unnecessary compatibility dilemmas. Change licensing terms to the GNU General Public License Version 2, or any later version, with written permission from all current and past contributors, namely: myself, David Gibson, Laine Stump, Andrea Bolognani, Paul Holzinger, Richard W.M. Jones, Chris Kuhn, Florian Weimer, Giuseppe Scrivano, Stefan Hajnoczi, and Vasiliy Ulyanov. Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
648 lines
28 KiB
Markdown
648 lines
28 KiB
Markdown
<!---
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SPDX-License-Identifier: GPL-2.0-or-later
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Copyright (c) 2021-2022 Red Hat GmbH
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Author: Stefano Brivio <sbrivio@redhat.com>
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-->
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<style scoped>
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.mobile_hide {
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visibility: hidden;
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display: none;
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display: none;
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}
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margin: 10px;
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visibility: hidden;
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display: none;
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}
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}
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</style>
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# passt: Plug A Simple Socket Transport
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_passt_ implements a translation layer between a Layer-2 network interface and
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native Layer-4 sockets (TCP, UDP, ICMP/ICMPv6 echo) on a host. It doesn't
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require any capabilities or privileges, and it can be used as a simple
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replacement for Slirp.
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<div class="mobile_hide">
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<picture>
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<source type="image/webp" srcset="/builds/latest/web/passt_overview.webp">
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<source type="image/png" srcset="/builds/latest/web/passt_overview.png">
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<img src="/builds/latest/web/passt_overview.png" usemap="#image-map" class="bright" style="z-index: 20; position: relative;" alt="Overview diagram of passt">
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</picture>
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for (var i = 0; i < map_areas.length; i++) {
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map_areas[i].onmouseout = map_out;
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}
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</script>
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# pasta: Pack A Subtle Tap Abstraction
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_pasta_ (same binary as _passt_, different command) offers equivalent
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functionality, for network namespaces: traffic is forwarded using a tap
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interface inside the namespace, without the need to create further interfaces on
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the host, hence not requiring any capabilities or privileges.
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It also implements a tap bypass path for local connections: packets with a local
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destination address are moved directly between Layer-4 sockets, avoiding Layer-2
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translations, using the _splice_(2) and _recvmmsg_(2)/_sendmmsg_(2) system calls
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for TCP and UDP, respectively.
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<div class="mobile_hide">
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<picture>
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<source type="image/webp" srcset="/builds/latest/web/pasta_overview.webp">
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<source type="image/png" srcset="/builds/latest/web/pasta_overview.png">
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<img src="/builds/latest/web/passt_overview.png" class="bright" style="z-index: 20; position: relative;" alt="Overview diagram of pasta">
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</picture>
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</div>
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- [Motivation](#motivation)
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- [Features](#features)
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- [Interfaces and Environment](#interfaces-and-environment)
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- [Services](#services)
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- [Addresses](#addresses)
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- [Protocols](#protocols)
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- [Ports](#ports)
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- [Demo](#demo)
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- [Continuous Integration](#continuous-integration)
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- [Performance](#performance_1)
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- [Try it](#try-it)
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- [Contribute](#contribute)
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- [Security and Vulnerability Reports](#security-and-vulnerability-reports)
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See also the [man page](/builds/latest/web/passt.1.html).
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## Motivation
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### passt
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When container workloads are moved to virtual machines, the network traffic is
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typically forwarded by interfaces operating at data link level. Some components
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in the containers ecosystem (such as _service meshes_), however, expect
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applications to run locally, with visible sockets and processes, for the
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purposes of socket redirection, monitoring, port mapping.
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To solve this issue, user mode networking, as provided e.g. by _libslirp_,
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can be used. Existing solutions implement a full TCP/IP stack, replaying traffic
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on sockets that are local to the pod of the service mesh. This creates the
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illusion of application processes running on the same host, eventually separated
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by user namespaces.
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While being almost transparent to the service mesh infrastructure, that kind of
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solution comes with a number of downsides:
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* three different TCP/IP stacks (guest, adaptation and host) need to be
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traversed for every service request
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* addressing needs to be coordinated to create the pretense of consistent
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addresses and routes between guest and host environments. This typically needs
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a NAT with masquerading, or some form of packet bridging
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* the traffic seen by the service mesh and observable externally is a distant
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replica of the packets forwarded to and from the guest environment:
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* TCP congestion windows and network buffering mechanisms in general operate
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differently from what would be naturally expected by the application
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* protocols carrying addressing information might pose additional challenges,
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as the applications don't see the same set of addresses and routes as they
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would if deployed with regular containers
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_passt_ implements a thinner layer between guest and host, that only implements
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what's strictly needed to pretend processes are running locally. The TCP
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adaptation doesn't keep per-connection packet buffers, and reflects observed
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sending windows and acknowledgements between the two sides. This TCP adaptation
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is needed as _passt_ runs without the `CAP_NET_RAW` capability: it can't create
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raw IP sockets on the pod, and therefore needs to map packets at Layer-2 to
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Layer-4 sockets offered by the host kernel.
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See also a
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[detailed illustration](https://gitlab.com/abologna/kubevirt-and-kvm/-/blob/master/Networking.md)
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of the problem and what lead to this approach.
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### pasta
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On Linux, regular users can create network namespaces and run application
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services inside them. However, connecting namespaces to other namespaces and to
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external hosts requires the creation of network interfaces, such as `veth`
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pairs, which needs in turn elevated privileges or the `CAP_NET_ADMIN`
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capability. _pasta_, similarly to _slirp4netns_, solves this problem by creating
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a tap interface available to processes in the namespace, and mapping network
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traffic outside the namespace using native Layer-4 sockets.
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Existing approaches typically implement a full, generic TCP/IP stack for this
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translation between data and transport layers, without the possibility of
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speeding up local connections, and usually requiring NAT. _pasta_:
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* avoids the need for a generic, full-fledged TCP/IP stack by coordinating TCP
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connection dynamics between sender and receiver
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* offers a fast bypass path for local connections: if a process connects to
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another process on the same host across namespaces, data is directly forwarded
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using pairs of Layer-4 sockets
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* with default options, maps routing and addressing information to the
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namespace, avoiding any need for NAT
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## Features
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✅: done/supported, ❌: out of scope, 🛠: in progress/being considered
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⌚: nice-to-have, eventually
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### Protocols
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* ✅ IPv4
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* ✅ all features, except for
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* ❌ fragmentation
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* ✅ IPv6
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* ✅ all features, except for
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* ❌ fragmentation
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* ❌ jumbograms
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* ✅ [TCP](/passt/tree/tcp.c)
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* ✅ Window Scaling (RFC 7323)
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* ✅ Defenses against Sequence Number Attacks (RFC 6528)
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* ⌚ [Protection Against Wrapped Sequences](https://bugs.passt.top/show_bug.cgi?id=1) (PAWS, RFC 7323)
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* ⌚ [Timestamps](https://bugs.passt.top/show_bug.cgi?id=1) (RFC 7323)
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* ❌ Selective Acknowledgment (RFC 2018)
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* ✅ [UDP](/passt/tree/udp.c)
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* ✅ ICMP/ICMPv6 Echo
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* ⌚ [IGMP/MLD](https://bugs.passt.top/show_bug.cgi?id=2) proxy
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* ⌚ [SCTP](https://bugs.passt.top/show_bug.cgi?id=3)
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### Portability
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* Linux
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* ✅ starting from 4.18 kernel version
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* ✅ starting from 3.13 kernel version
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* ✅ run-time selection of AVX2 build
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* C libraries:
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* ✅ glibc
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* ✅ [_musl_](https://bugs.passt.top/show_bug.cgi?id=4)
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* ⌚ [_uClibc-ng_](https://bugs.passt.top/show_bug.cgi?id=5)
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* ⌚ [FreeBSD](https://bugs.passt.top/show_bug.cgi?id=6),
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[Darwin](https://bugs.passt.top/show_bug.cgi?id=6)
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* ⌚ [NetBSD](https://bugs.passt.top/show_bug.cgi?id=7),
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[OpenBSD](https://bugs.passt.top/show_bug.cgi?id=7)
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* ⌚ [Win2k](https://bugs.passt.top/show_bug.cgi?id=8)
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### Security
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* ✅ no dynamic memory allocation (`sbrk`(2), `brk`(2), `mmap`(2) [blocked via
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`seccomp`](/passt/tree/seccomp.sh))
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* ✅ root operation not allowed outside user namespaces
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* ✅ all capabilities dropped, other than `CAP_NET_BIND_SERVICE` (if granted)
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* ✅ with default options, user, mount, IPC, UTS, PID namespaces are detached
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* ✅ no external dependencies (other than a standard C library)
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* ✅ restrictive seccomp profiles (30 syscalls allowed for _passt_, 41 for
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_pasta_ on x86_64)
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* ✅ examples of [AppArmor](/passt/tree/contrib/apparmor) and
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[SELinux](/passt/tree/contrib/selinux) profiles available
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* ✅ static checkers in continuous integration (clang-tidy, cppcheck)
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* ✅️ clearly defined boundary-checked packet abstraction
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* 🛠️ ~5 000 LoC target
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* ⌚ [fuzzing](https://bugs.passt.top/show_bug.cgi?id=9), _packetdrill_ tests
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* ⌚ stricter [synflood protection](https://bugs.passt.top/show_bug.cgi?id=10)
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* 💡 [add](https://lists.passt.top/) [your](https://bugs.passt.top/)
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[ideas](https://chat.passt.top)
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### Configurability
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* ✅ all addresses, ports, port ranges
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* ✅ optional NAT, not required
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* ✅ all protocols
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* ✅ _pasta_: auto-detection of bound ports
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* ⌚ run-time configuration of port ranges without autodetection
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* ⌚ configuration of port ranges for autodetection
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* 💡 [add](https://lists.passt.top/) [your](https://bugs.passt.top/)
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[ideas](https://chat.passt.top)
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### Performance
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* ✅ maximum two (cache hot) copies on every data path
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* ✅ _pasta_: zero-copy for local connections by design (no configuration
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needed)
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* ✅ generalised coalescing and batching on every path for every supported
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protocol
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* ✅ 4 to 50 times IPv4 TCP throughput of existing, conceptually similar
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solutions depending on MTU (UDP and IPv6 hard to compare)
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* 🛠 [_vhost-user_ support](https://bugs.passt.top/show_bug.cgi?id=25) for
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maximum one copy on every data path and lower request-response latency
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* ⌚ [multithreading](https://bugs.passt.top/show_bug.cgi?id=13)
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* ⌚ [raw IP socket support](https://bugs.passt.top/show_bug.cgi?id=14) if
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`CAP_NET_RAW` is granted
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* ⌚ eBPF support (might not improve performance over vhost-user)
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### Interfaces
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* ✅ native [qemu](https://bugs.passt.top/show_bug.cgi?id=11) support (_passt_)
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* ✅ native [libvirt](https://bugs.passt.top/show_bug.cgi?id=12) support
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(_passt_)
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* ✅ Podman [integration](https://github.com/containers/podman/pull/16141)
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(_pasta_)
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* ✅ bug-to-bug compatible
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[_slirp4netns_ replacement](/passt/tree/slirp4netns.sh)
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* ✅ out-of-tree patch for
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[Kata Containers](/passt/tree/contrib/kata-containers) available
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* ⌚ drop-in replacement for VPNKit (rootless Docker)
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### Availability
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* ✅ official [packages](https://gitlab.com/redhat/centos-stream/rpms/passt) for
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CentOS Stream
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* ✅ official [packages](https://tracker.debian.org/pkg/passt) for Debian
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* ✅ official [packages](https://src.fedoraproject.org/rpms/passt) for Fedora
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* ✅ official [packages](https://packages.ubuntu.com/lunar/passt) for Ubuntu
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* ✅ unofficial [packages](https://aur.archlinux.org/packages/passt-git) for
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Arch Linux
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* ✅ unofficial
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[packages](https://copr.fedorainfracloud.org/coprs/sbrivio/passt/) for EPEL,
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Mageia
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* 🛠 official
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[packages](https://build.opensuse.org/package/show/Virtualization:containers/passt)
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for openSUSE
|
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* ✅ unofficial [packages](https://passt.top/builds/latest/x86_64/) from x86_64
|
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static builds for other RPM-based distributions
|
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* ✅ unofficial [packages](https://passt.top/builds/latest/x86_64/) from x86_64
|
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static builds for other Debian-based distributions
|
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* ✅ testing on non-x86_64 architectures (aarch64, armv7l, i386, ppc64, ppc64le,
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s390x)
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### Services
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* ✅ built-in [ARP proxy](/passt/tree/arp.c)
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* ✅ minimalistic [DHCP server](/passt/tree/dhcp.c)
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* ✅ minimalistic [NDP proxy](/passt/tree/ndp.c) with router advertisements and
|
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SLAAC support
|
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* ✅ minimalistic [DHCPv6 server](/passt/tree/dhcpv6.c)
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* ⌚ fine-grained configurability of DHCP, NDP, DHCPv6 options
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## Interfaces and Environment
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_passt_ exchanges packets with _qemu_ via UNIX domain socket, using the `socket`
|
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back-end in qemu. This is supported since qemu 7.2.
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|
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For older versions, the [qrap](/passt/tree/qrap.c) wrapper can be used to
|
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connect to a UNIX domain socket and to start qemu, which can now use the file
|
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descriptor that's already opened.
|
|
|
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This approach, compared to using a _tap_ device, doesn't require any security
|
|
capabilities, as we don't need to create any interface.
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|
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_pasta_ runs out of the box with any recent (post-3.8) Linux kernel.
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## Services
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|
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_passt_ and _pasta_ provide some minimalistic implementations of networking
|
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services:
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|
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* [ARP proxy](/passt/tree/arp.c), that resolves the address of
|
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the host (which is used as gateway) to the original MAC address of the host
|
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* [DHCP server](/passt/tree/dhcp.c), a simple implementation
|
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handing out one single IPv4 address to the guest or namespace, namely, the
|
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same address as the first one configured for the upstream host interface, and
|
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passing the nameservers configured on the host
|
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* [NDP proxy](/passt/tree/ndp.c), which can also assign prefix
|
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and nameserver using SLAAC
|
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* [DHCPv6 server](/passt/tree/dhcpv6.c): a simple
|
|
implementation handing out one single IPv6 address to the guest or namespace,
|
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namely, the the same address as the first one configured for the upstream host
|
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interface, and passing the nameservers configured on the host
|
|
|
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## Addresses
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|
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For IPv4, the guest or namespace is assigned, via DHCP, the same address as the
|
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upstream interface of the host, and the same default gateway as the default
|
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gateway of the host. Addresses are translated in case the guest is seen using a
|
|
different address from the assigned one.
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|
|
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For IPv6, the guest or namespace is assigned, via SLAAC, the same prefix as the
|
|
upstream interface of the host, the same default route as the default route of
|
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the host, and, if a DHCPv6 client is running in the guest or namespace, also the
|
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same address as the upstream address of the host. This means that, with a DHCPv6
|
|
client in the guest or namespace, addresses don't need to be translated. Should
|
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the client use a different address, the destination address is translated for
|
|
packets going to the guest or to the namespace.
|
|
|
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### Local connections with _passt_
|
|
|
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For UDP and TCP, for both IPv4 and IPv6, packets from the host addressed to a
|
|
loopback address are forwarded to the guest with their source address changed to
|
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the address of the gateway or first hop of the default route. This mapping is
|
|
reversed on the other way.
|
|
|
|
### Local connections with _pasta_
|
|
|
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Packets addressed to a loopback address in either namespace are directly
|
|
forwarded to the corresponding (or configured) port in the other namespace.
|
|
Similarly as _passt_, packets from the non-init namespace addressed to the
|
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default gateway, which are therefore sent via the tap device, will have their
|
|
destination address translated to the loopback address.
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|
|
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## Protocols
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|
|
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_passt_ and _pasta_ support TCP, UDP and ICMP/ICMPv6 echo (requests and
|
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replies). More details about the TCP implementation are described in the
|
|
[theory of operation](/passt/tree/tcp.c), and similarly for
|
|
[UDP](/passt/tree/udp.c).
|
|
|
|
An IGMP/MLD proxy is currently work in progress.
|
|
|
|
## Ports
|
|
|
|
### passt
|
|
|
|
To avoid the need for explicit port mapping configuration, _passt_ can bind to
|
|
all unbound non-ephemeral (0-49152) TCP and UDP ports. Binding to low ports
|
|
(0-1023) will fail without additional capabilities, and ports already bound
|
|
(service proxies, etc.) will also not be used. Smaller subsets of ports, with
|
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port translations, are also configurable.
|
|
|
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UDP ephemeral ports are bound dynamically, as the guest uses them.
|
|
|
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If all ports are forwarded, service proxies and other services running in the
|
|
container need to be started before _passt_ starts.
|
|
|
|
### pasta
|
|
|
|
With default options, _pasta_ scans for bound ports on init and non-init
|
|
namespaces, and automatically forwards them from the other side. Port forwarding
|
|
is fully configurable with command line options.
|
|
|
|
## Demo
|
|
|
|
### pasta
|
|
|
|
<link rel="stylesheet" type="text/css" href="/static/asciinema-player.css" />
|
|
<script src="/static/asciinema-player.min.js"></script>
|
|
|
|
<div class="mobile_hide" id="demo_pasta_div" style="display: grid; grid-template-columns: 1fr 1fr;">
|
|
<div id="demo_pasta" style="width: 99%;"></div>
|
|
<div id="demo_podman" style="width: 99%;"></div>
|
|
</div>
|
|
<script>
|
|
if (getComputedStyle(document.getElementById('demo_pasta_div'))['visibility'] == "visible") {
|
|
demo_pasta_player = AsciinemaPlayer.create('/builds/latest/web/demo_pasta.cast',
|
|
document.getElementById('demo_pasta'),
|
|
{ cols: 130, rows: 41,
|
|
preload: true, poster: 'npt:0:4'
|
|
});
|
|
|
|
demo_podman_player = AsciinemaPlayer.create('/builds/latest/web/demo_podman.cast',
|
|
document.getElementById('demo_podman'),
|
|
{ cols: 130, rows: 41,
|
|
preload: true, poster: 'npt:0:4'
|
|
});
|
|
}
|
|
</script>
|
|
<div class="mobile_show">
|
|
<p><a href="/builds/latest/web/demo_pasta.html">Overview of pasta functionality</a></p>
|
|
<p><a href="/builds/latest/web/demo_podman.html">Overview of Podman operation with pasta</a></p>
|
|
</div>
|
|
|
|
### passt
|
|
|
|
<div class="mobile_hide" id="demo_passt" style="width: 70%; height: auto; max-height: 90%"></div>
|
|
<script>
|
|
if (getComputedStyle(document.getElementById('demo_passt'))['visibility'] == "visible") {
|
|
demo_passt_player = AsciinemaPlayer.create('/builds/latest/web/demo_passt.cast',
|
|
document.getElementById('demo_passt'),
|
|
{ cols: 130, rows: 41,
|
|
preload: true, poster: 'npt:0:4'
|
|
});
|
|
}
|
|
</script>
|
|
<div class="mobile_show">
|
|
<p><a href="/builds/latest/web/demo_passt.html">Overview of passt functionality</a></p>
|
|
</div>
|
|
|
|
## Continuous Integration
|
|
|
|
<div class="mobile_hide" id="ci" style="width: 90%; height: auto; max-height: 90%"></div>
|
|
<script>
|
|
if (getComputedStyle(document.getElementById('ci'))['visibility'] == "visible") {
|
|
ci_player = AsciinemaPlayer.create('/builds/latest/web/ci.cast',
|
|
document.getElementById('ci'),
|
|
{ cols: 240, rows: 51, poster: 'npt:999:0' }
|
|
);
|
|
}
|
|
</script>
|
|
<div class="mobile_hide"><script src="/builds/latest/web/ci.js"></script></div>
|
|
<div class="mobile_show">
|
|
<p><a href="/builds/latest/web/ci.html">Continuous integration test run</a></p>
|
|
</div>
|
|
|
|
See also the [test logs](/builds/latest/test/).
|
|
|
|
## Performance
|
|
|
|
<script src="/builds/latest/web/perf.js"></script>
|
|
|
|
## Try it
|
|
|
|
### passt
|
|
|
|
* build from source:
|
|
|
|
git clone https://passt.top/passt
|
|
cd passt
|
|
make
|
|
|
|
* alternatively, install one of the [available packages](#availability)
|
|
|
|
Static binaries and packages are simply built with:
|
|
|
|
make pkgs
|
|
|
|
* have a look at the _man_ page for synopsis and options:
|
|
|
|
man ./passt.1
|
|
|
|
* run the demo script, that detaches user and network namespaces, configures the
|
|
new network namespace using `pasta`, starts `passt` and, optionally, `qemu`:
|
|
|
|
doc/demo.sh
|
|
|
|
* alternatively, you can use
|
|
[libvirt](https://libvirt.org/formatdomain.html#userspace-slirp-or-passt-connection)
|
|
to start QEMU
|
|
|
|
* and that's it, you should now have TCP connections, UDP, and ICMP/ICMPv6
|
|
echo working from/to the guest for IPv4 and IPv6
|
|
|
|
* to connect to a service on the VM, just connect to the same port directly
|
|
with the address of the current network namespace
|
|
|
|
### pasta
|
|
|
|
* build from source:
|
|
|
|
git clone https://passt.top/passt
|
|
cd passt
|
|
make
|
|
|
|
* alternatively, install one of the [available packages](#availability)
|
|
|
|
Static binaries and packages are simply built with:
|
|
|
|
make pkgs
|
|
|
|
* have a look at the _man_ page for synopsis and options:
|
|
|
|
man ./pasta.1
|
|
|
|
* start pasta with:
|
|
|
|
./pasta
|
|
|
|
* alternatively, use it directly with Podman (since Podman 4.3.2, or with
|
|
commit [`aa47e05ae4a0`](https://github.com/containers/podman/commit/aa47e05ae4a0d14a338cbe106b7eb9cdf098a529)):
|
|
|
|
podman run --net=pasta ...
|
|
|
|
* you're now inside a new user and network namespace. For IPv6, SLAAC happens
|
|
right away as _pasta_ sets up the interface, but DHCPv6 support is available
|
|
as well. For IPv4, configure the interface with a DHCP client:
|
|
|
|
dhclient
|
|
|
|
and, optionally:
|
|
|
|
dhclient -6
|
|
|
|
* alternatively, start pasta as:
|
|
|
|
./pasta --config-net
|
|
|
|
to let pasta configure networking in the namespace by itself, using
|
|
`netlink`
|
|
|
|
* ...or run the demo script:
|
|
|
|
doc/demo.sh
|
|
|
|
* and that's it, you should now have TCP connections, UDP, and ICMP/ICMPv6
|
|
echo working from/to the namespace for IPv4 and IPv6
|
|
|
|
* to connect to a service inside the namespace, just connect to the same port
|
|
using the loopback address.
|
|
|
|
## Contribute
|
|
|
|
### [Mailing Lists](/passt/lists)
|
|
* Submit, review patches, and discuss development ideas on
|
|
[`passt-dev`](https://lists.passt.top/postorius/lists/passt-dev.passt.top/)
|
|
|
|
* Ask your questions and discuss usage needs on
|
|
[`passt-user`](https://lists.passt.top/postorius/lists/passt-user.passt.top/)
|
|
|
|
### [Bug Reports and Feature Requests](/passt/bugs)
|
|
* **Pick up an [open bug](https://bugs.passt.top/buglist.cgi?bug_severity=blocker&bug_severity=quite%20bad&bug_severity=normal&bug_severity=minor&columnlist=bug_status%2Ccomponent%2Cpriority%2Cbug_severity%2Cassigned_to%2Cshort_desc%2Cchangeddate&known_name=Open%20bugs%2C%20by%20priority&list_id=85&query_based_on=Open%20bugs%2C%20by%20priority&query_format=advanced&resolution=---)**
|
|
* **Implement a [feature request](https://bugs.passt.top/buglist.cgi?bug_severity=enhancement&bug_severity=feature&columnlist=bug_status%2Ccomponent%2Cpriority%2Cbug_severity%2Cassigned_to%2Cshort_desc%2Cchangeddate&known_name=Features%2C%20by%20priority&list_id=81&order=priority%2Cbug_status%2Cassigned_to%2Cbug_id&query_based_on=Features%2C%20by%20priority&query_format=advanced&resolution=---)**
|
|
* Browse all [open items](https://bugs.passt.top/buglist.cgi?columnlist=bug_status%2Ccomponent%2Cpriority%2Cbug_severity%2Cassigned_to%2Cshort_desc%2Cchangeddate&known_name=All%20items%2C%20by%20priority&list_id=83&query_based_on=All%20items%2C%20by%20priority&query_format=advanced&resolution=---)
|
|
* ...or [file a bug](https://bugs.passt.top/enter_bug.cgi)
|
|
|
|
### [Chat](/passt/chat)
|
|
* Somebody might be available on [IRC](https://irc.passt.top) on `#passt` at
|
|
[Libera.Chat](https://libera.chat/)
|
|
|
|
### Weekly development [meeting](https://pad.passt.top/p/weekly)
|
|
* Open to everybody! Feel free to join and propose a different time directly on
|
|
the agenda.
|
|
|
|
## Security and Vulnerability Reports
|
|
|
|
* Please send an email to [passt-sec](mailto:passt-sec@passt.top), private list,
|
|
no subscription required
|