PPP IPv6CP: Incorrect payload length warning
Summary
Padding is very common in PPP IPCP and IPv6CP packets. In PPP IPCP packets this does not generate a warning, the payload length is calculated and accepted without padding. For IPv6CP packets, on the other hand, a warning is displayed if the packet is padded. I'm not sure which behavior is better, but it should at least be consistent. From my point of view padding should not generate a warning, but I may be wrong.
Sample capture file
Example attached.
PPP_IPv6CP_payload_length_warning.pcapng
Steps to reproduce
The example was created with a OneAccess/Ekinops One20SG router with firmware V5.2R1E17_HA3. One20SG5E_IPv4+IPv6.txt
What is the current bug behavior?
What is the expected correct behavior?
Either no warning or equally a warning for IPCP and IPv6CP.
Build information
Version 4.0.6 (v4.0.6-0-gac2f5a01286a).
Compiled (64-bit) using Microsoft Visual Studio 2022 (VC++ 14.32, build 31332),
with GLib 2.72.3, with PCRE2, with zlib 1.2.12, with Qt 5.15.2, with libpcap,
with Lua 5.2.4, with GnuTLS 3.6.3 and PKCS #11 support, with Gcrypt 1.10.1, with
Kerberos (MIT), with MaxMind, with nghttp2 1.46.0, with brotli, with LZ4, with
Zstandard, with Snappy, with libxml2 2.9.14, with libsmi 0.4.8, with
QtMultimedia, with automatic updates using WinSparkle 0.5.7, with AirPcap, with
SpeexDSP (using bundled resampler), with Minizip, with binary plugins.
Running on 64-bit Windows 10 (22H2), build 19045, with Intel(R) Core(TM)
i5-3320M CPU @ 2.60GHz (with SSE4.2), with 3959 MB of physical memory, with GLib
2.72.3, with PCRE2 10.40 2022-04-14, with Qt 5.15.2, with Npcap version 1.71,
based on libpcap version 1.10.2-PRE-GIT, with c-ares 1.18.1, with GnuTLS 3.6.3,
with Gcrypt 1.10.1, with nghttp2 1.46.0, with brotli 1.0.9, with LZ4 1.9.3, with
Zstandard 1.5.2, without AirPcap, with light display mode, without HiDPI, with
LC_TYPE=German_Germany.utf8, binary plugins supported.