Package the Linux desktop head as an RPM, and publish a nightly one

The third desktop platform shipped as nothing: a checkout somebody built.
VelopackUpdateChannel already named the two platforms it serves rather than
negating the one it does not, so that a Linux package would be an addition
there rather than something that had silently half-happened. This is it, and
it is deliberately not a Velopack channel.

There is no updater in the package at all. On this platform dnf is already an
updater the user trusts, audits and controls, and a second one answering to
this project instead is the capability ADR 0013 rule 4 spends a page keeping
unsettable. The cost is real and is written down rather than glossed: nothing
tells a Linux user that a newer build exists, because there is no repository
to tell them.

Rule 3 is untouched. The build job packages the release-shaped RPM on every
main build and every tag and uploads nothing, exactly as it does for Windows
and macOS; the desktop job packages the nightly-shaped one and puts it on the
rolling nightly-desktop release beside the Windows feed. Two RPMs with
different names owning different paths cannot replace one another, so rule 9's
separations come almost free here — the profile split still belongs to the
build, through DodoChannel.

vpk verifies that what it packs actually calls VelopackApp.Build().Run(), and
nothing here does that for us, so scripts/ci-linux-rpm.sh makes its own
assertions: it asks the finished package what it requires, what it provides,
what it holds and what modes those carry. Two of those checks exist because
the first realistic payload tripped them.

  - .NET's libmscordbi.so links libmscordaccore.so. With bundled provides
    excluded — which they must be, or this package would advertise libcoreclr
    to the whole system — that produced a dependency no host on earth can
    satisfy. The requires exclusion is computed from the payload rather than
    listed, because a list of Microsoft's internal file names goes stale in
    the direction that yields an uninstallable package.

  - cp -a inherits the publish directory's modes, and off the wrong filesystem
    that meant a world-writable /opt/DodoSSH: any local account able to
    replace the SSH client every other account runs. For an application
    holding a team's credentials in plaintext that is the trust model walked
    around rather than attacked. Every mode is now set absolutely.

Verified as far as a runner can: both packages install side by side on Fedora
44, resolve webkit2gtk4.1 2.52.5 — the backend MainWindow records as measured
— keep separate launchers, icons and profiles, and dnf remove takes one tree
and leaves the other. 0.0.1~alpha.0.143 sorts below both 0.0.1 and the next
height. What no runner can answer is Phase 19, which is new and unwalked.

RHEL 9 is deliberately not claimed. It ships WebKitGTK's 4.0 line under
libwebkit2gtk-4.0.so.37, and an or-branch for it was written and then removed:
nobody has run the head there, and dnf refusing with "nothing provides
libwebkit2gtk-4.1.so.0" is a better answer than an install that draws a blank
terminal. Same sentence, and the same reason, as the missing Intel Mac.

x86_64 only, for that reason and not a different one.

build/linux/dodossh.spec

@@ -0,0 +1,294 @@
+# ==================================================================================================
+#  The Linux desktop head, as an RPM.
+#
+#  Built by scripts/ci-linux-rpm.sh, which is what supplies every dodo_* macro below and what checks
+#  the result. Nothing here is invoked by hand; `rpmbuild -bb` on this file with no --define set will
+#  fail on the Version line, which is the intended way round.
+#
+#  ◆ WHY THIS IS AN RPM AND NOT A VELOPACK RELEASE, WHICH IS THE FIRST QUESTION.
+#
+#  Both desktop platforms that ship today are Velopack: the client polls the project's forge, fetches
+#  a newer build and swaps itself over. ADR 0013 rule 4 is what makes that safe to hold — the feed
+#  address is a const, so no operator can answer "is there a newer version" on the user's behalf.
+#
+#  This package has no updater in it at all, and that is deliberate rather than unfinished.
+#  VelopackUpdateChannel.ForThisMachine already refuses every platform that is not Windows or macOS,
+#  and it says why in a comment worth not undoing: a client handed an UpdateManager pointed at a feed
+#  carrying nothing it can apply is a client that reports itself current forever. On Linux the
+#  package manager is the updater — `dnf upgrade` is a mechanism the user already trusts, already
+#  audits and already controls — so the honest thing is to be an ordinary package and let it do that,
+#  rather than to bolt on a second one that answers to a different authority.
+#
+#  The consequence to know: an installed RPM learns about a new version when its repository does, and
+#  this project publishes no repository yet. Somebody who downloaded the file installs the next one
+#  the same way.
+# ==================================================================================================
+
+# ◆ THE THREE THINGS THAT MUST BE TURNED OFF, AND WHAT EACH ONE WOULD DO.
+#
+# __os_install_post is the chain of brp-* scripts rpm runs over the buildroot: strip, strip-static,
+# compress, elfperms. Every one of them is wrong here. The payload is a published .NET tree whose
+# managed PDBs ADR 0013 rule 6 keeps on purpose — a stack with file names and line numbers is this
+# project's entire diagnostic channel — and brp-strip would take the native symbols with them for a
+# saving nobody asked for. It also runs the host's binutils over glibc binaries on a build host that
+# is musl, which is a class of breakage with no good failure message.
+#
+# debug_package would then try to build a -debuginfo subpackage out of what strip extracted, from
+# third-party binaries nobody here will ever step through.
+#
+# _build_id_links is the one that surprises people, because turning the other two off does not turn
+# it off: rpm still writes /usr/lib/.build-id/<xx>/<hash> symlinks for every ELF file in the payload.
+# For a bundled tree that means dozens of links in a system directory this package has no business
+# owning, and two files with the same build id — which a .NET publish does produce — make it a build
+# *warning* about duplicates rather than an error, so it goes unnoticed.
+%global __os_install_post %{nil}
+%global debug_package     %{nil}
+%global _build_id_links   none
+
+# ◆ AUTO-REQUIRES STAYS ON. AUTO-PROVIDES DOES NOT. THE ASYMMETRY IS THE WHOLE POINT.
+#
+# rpm's elfdeps reads DT_NEEDED and the symbol-version table out of every ELF file in the buildroot,
+# and the requires half of that is worth much more than a hand-written list: it produces
+# `libc.so.6(GLIBC_2.38)(64bit)` rather than `glibc`, so the package refuses to install on a host
+# whose glibc is too old instead of installing and dying at the first launch. A hand list cannot
+# express that and would go stale the first time a dependency changed underneath it.
+#
+# It reads ELF directly rather than by loading anything, so it does this correctly for x86_64 glibc
+# binaries on a musl build host — which is what lets this package be built on the same Alpine runner
+# as everything else in ci.yml.
+#
+# The provides half is the opposite. Everything under /opt here is a *bundled* copy: libSkiaSharp,
+# libcoreclr, libe_sqlite3 and the rest belong to this application and to nothing else. Left on,
+# this package would advertise `libcoreclr.so()(64bit)` to the whole system, and some other package's
+# dependency could then be satisfied by a private copy inside a directory `dnf remove dodossh` takes
+# away. Excluding the tree by path is the standard shape for that and costs nothing, because nothing
+# outside this package is meant to link against anything inside it.
+#
+# ◆ WHICH IS WHY THE REQUIRES SIDE NEEDS AN EXCLUSION TOO, AND WHY IT IS COMPUTED.
+#
+# The two halves are not independent. A bundled library with a DT_NEEDED on another bundled library
+# produces a requirement for a soname this package carries and — after the exclusion above — no
+# longer advertises, which no host on earth can satisfy. It is not hypothetical and it is not rare:
+# .NET's own libmscordbi.so links libmscordaccore.so, so the very first realistic payload this was
+# tried against produced a package `dnf install` refuses outright.
+#
+# dodo_bundled is the alternation of every lib*.so* filename in the payload, worked out by
+# scripts/ci-linux-rpm.sh from the tree it was handed rather than listed here. A list in this file
+# would be a list of Microsoft's and SkiaSharp's internal file names, kept in step by hand, and its
+# failure mode is the uninstallable package above.
+#
+# liblttng-ust is excluded on its own terms and not because it is bundled — it is not. It is what
+# libcoreclrtraceptprovider.so links, and that file exists so that CoreCLR can emit LTTng trace
+# events if a host has the tracing stack. Nothing here asks it to. The file is kept and the
+# requirement is dropped, which is the arrangement that works both ways round: where liblttng-ust is
+# present the dlopen succeeds and tracing is available, and where it is absent CoreCLR carries on, as
+# it does on every machine that runs a .NET application without it. Requiring it instead would put
+# the package out of reach on RHEL, where lttng-ust is in EPEL rather than in the base repositories —
+# an install failure on a supported distribution, in exchange for a tracing integration this
+# application does not use.
+#
+# scripts/ci-linux-rpm.sh checks the finished package against its own file list afterwards, because
+# an exclusion that silently stopped matching would put the uninstallable package back with no
+# warning anywhere.
+%global __provides_exclude_from ^/opt/.*$
+%global __requires_exclude      ^(liblttng-ust\.so|%{dodo_bundled})
+
+Name:           %{dodo_name}
+Version:        %{dodo_version}
+Release:        %{dodo_release}
+Summary:        SSH client with an end-to-end encrypted credential vault
+License:        MIT
+URL:            https://git.dodotech.cloud/DodoTech-Public/DodoSSH
+BuildArch:      x86_64
+
+# ◆ THE DEPENDENCIES elfdeps CANNOT SEE, WHICH ARE THE ONES THE PRODUCT IS MADE OF.
+#
+# Everything below is reached through dlopen, by a name composed at runtime, so it appears in no
+# DT_NEEDED entry anywhere in the payload. Left to the automatic scan the package would install
+# cleanly on a host with none of it and fail at the first window.
+#
+# GTK and WebKitGTK are the terminal. Avalonia.Controls.WebView P/Invokes a bare `libwebkit2gtk` and
+# a bare `libgtk` and resolves them itself, and MainWindow.OnTerminalEnvironmentRequested documents
+# the backend it was measured against: WebKitGTK 2.52.5 on Fedora 44, which is the 4.1 API line — the
+# assembly's one fully-spelled soname, libjavascriptcoregtk-4.1.so.0, is that line's other half.
+#
+# ◆ THE 4.0 LINE IS DELIBERATELY NOT CLAIMED, AND THE COST OF THAT IS KNOWN.
+#
+# The control's own diagnostic says "webkit2gtk 4.0+", so a dependency permitting either line is
+# tempting and was written first. RHEL 9 and its rebuilds are what it would buy: they ship
+# webkit2gtk3, which is the 4.0 API under the soname libwebkit2gtk-4.0.so.37 — not .so.0, which is
+# what makes this a thing to look up rather than guess. Requiring only 4.1 means `dnf install` on
+# AlmaLinux 9 refuses with "nothing provides libwebkit2gtk-4.1.so.0", by design.
+#
+# It is refused because nobody has run it. This project does not ship an Intel macOS package for the
+# same reason and says so in ADR 0013 decision 10 — the engineering is small and the verification is
+# the scarce thing — and an install that succeeds and then draws a blank terminal is a worse answer
+# than one that refuses in a sentence naming the missing library. The day somebody runs the head on
+# a 4.0 host, this becomes a rich `or` and a line in the README.
+#
+# libX11 is Avalonia's own backend, P/Invoked the same way. On Wayland this is satisfied by XWayland,
+# which every desktop shipping this package has.
+#
+# libicu is the one that looks removable and is not. DodoSSH.Client.App sets InvariantGlobalization
+# to false — deliberately, and the csproj says why: this process prints timestamps and host names to
+# a person who expects their own locale's conventions. A .NET process configured that way and given
+# no ICU does not degrade to invariant, it refuses to start. The bare package name is the Fedora and
+# RHEL spelling; it is the one name here that is a distribution's rather than a soname's, because ICU
+# bumps its soname on every release and pinning one would make this package expire.
+Requires:       libwebkit2gtk-4.1.so.0()(64bit)
+Requires:       libgtk-3.so.0()(64bit)
+Requires:       libgdk-3.so.0()(64bit)
+Requires:       libgio-2.0.so.0()(64bit)
+Requires:       libglib-2.0.so.0()(64bit)
+Requires:       libgobject-2.0.so.0()(64bit)
+Requires:       libX11.so.6()(64bit)
+Requires:       libicu
+
+# The size directories under /usr/share/icons/hicolor belong to hicolor-icon-theme and not to this
+# package, which is the right way round — every application drops icons into them. Depending on the
+# owner is how those directories come to exist at all on a minimal host, and how they get removed
+# again when the last thing using them goes.
+Requires:       hicolor-icon-theme
+
+%description
+DodoSSH is an SSH and SFTP client for teams whose credentials are shared and whose infrastructure is
+not. Hosts, keys and passphrases live in a vault that is encrypted on this machine and stays
+encrypted on the server, so the deployment holding a team's secrets can never read them.
+
+This package carries its own .NET runtime and is updated the way every other package on this system
+is; it contains no self-updater and contacts no update service.
+
+%install
+rm -rf %{buildroot}
+
+# ◆ /opt, AND NOT /usr/lib64/dodossh, WHICH IS THE MORE CONVENTIONAL PLACE.
+#
+# The Filesystem Hierarchy Standard reserves /opt for exactly this — an add-on package that arrives
+# as one self-contained tree — and that is what a published .NET application is: a runtime, thirty
+# managed assemblies and half a dozen native libraries that only make sense together and are only
+# ever loaded by each other. Scattering them into the system library directory would mix a bundled
+# libSkiaSharp in with the system's shared objects, which is the arrangement the provides exclusion
+# above exists to keep this package out of.
+#
+# The directory name carries the channel, so a release and a nightly are two trees rather than one
+# that overwrites the other. That is the same separation ADR 0013 rule 9 builds on Windows out of
+# pack ids, arrived at here for free: two RPMs with different names owning different paths cannot
+# replace one another, and dnf will say so rather than doing it. The profile directory is separated
+# by the build itself — DodoChannel=nightly is what ClientPaths reads to suffix it — so the two
+# installs share no state at all.
+mkdir -p %{buildroot}/opt/%{dodo_dir}
+cp -a %{dodo_payload}/. %{buildroot}/opt/%{dodo_dir}/
+
+# ◆ AND THE MODES ARE SET HERE RATHER THAN INHERITED, WHICH IS NOT TIDINESS.
+#
+# `cp -a` preserves what the publish directory happened to have, and what it happened to have is a
+# property of the filesystem it was written on rather than of anything decided here. rpmlint caught
+# the consequence on the first tree this was tried against: every file in the package was mode 777,
+# because the tree had come off a mount that reports everything that way.
+#
+# For this application that is not a lint warning, it is a hole. A world-writable /opt/DodoSSH lets
+# any local account replace the SSH client belonging to every other account on the machine — the
+# binary that holds a team's infrastructure credentials in plaintext while it runs, which is the
+# thing ADR 0001 spends its whole trust model on. Malware running as nobody-in-particular would not
+# need to attack the crypto; it would edit the client.
+#
+# Stated absolutely and in this order, so the answer does not depend on the publish at all:
+# directories and the things that are executed or loaded get 0755, and everything else — assemblies,
+# PDBs, the runtime config, the terminal's HTML and JavaScript — gets 0644. Owned by root, which is
+# rpm's default for a package that names no %attr user, and is what makes the modes mean anything.
+find %{buildroot}/opt/%{dodo_dir} -type d -exec chmod 0755 {} +
+find %{buildroot}/opt/%{dodo_dir} -type f -exec chmod 0644 {} +
+find %{buildroot}/opt/%{dodo_dir} -type f -name '*.so*' -exec chmod 0755 {} +
+
+# The two files a .NET publish means to be executed. createdump is the runtime's crash-dump helper
+# and is only present on some publishes, so it is conditional; the apphost never is, and the check
+# above this section has already refused a publish without one.
+chmod 0755 %{buildroot}/opt/%{dodo_dir}/DodoSSH
+[ -f %{buildroot}/opt/%{dodo_dir}/createdump ] && chmod 0755 %{buildroot}/opt/%{dodo_dir}/createdump
+true
+
+# The apphost is the thing to launch and every other file in the tree is loaded relative to it, so
+# what goes on PATH is a symlink rather than a copy or a wrapper script. .NET resolves its own
+# directory through /proc/self/exe, which follows the link, so a symlinked apphost finds its runtime
+# with no help — a wrapper exporting DOTNET_ROOT or cd-ing first would be solving a problem that
+# does not exist here, and would be one more file to keep in step with the layout.
+#
+# Relative — ../../opt from /usr/bin — rather than the absolute /opt path it resolves to. Both work
+# on a running system and only one works inside a chroot or an image being assembled somewhere other
+# than /, which is where absolute symlinks out of a package are checked and warned about.
+mkdir -p %{buildroot}%{_bindir}
+ln -s ../../opt/%{dodo_dir}/DodoSSH %{buildroot}%{_bindir}/%{dodo_bin}
+
+# ◆ THE DESKTOP ENTRY IS WRITTEN HERE RATHER THAN SHIPPED AS A SOURCE FILE.
+#
+# Three of its seven meaningful lines differ between the release and the nightly, and the two files
+# that would result are the kind of pair that drifts: somebody adds a MIME type to one of them and
+# nobody notices for a release. Composed from the same macros the rest of the layout uses, they
+# cannot.
+#
+# StartupWMClass is the line that is easy to leave out and visibly wrong without: Avalonia sets
+# WM_CLASS from the assembly name, which is DodoSSH for both channels, so without this a launched
+# window is a second, unlabelled icon in the dock beside the one that launched it. It is the assembly
+# name deliberately and not the package's binary name — the window does not know which package
+# started it.
+mkdir -p %{buildroot}%{_datadir}/applications
+cat > %{buildroot}%{_datadir}/applications/%{dodo_bin}.desktop <<DESKTOP
+[Desktop Entry]
+Type=Application
+Version=1.0
+Name=%{dodo_title}
+GenericName=SSH Client
+Comment=SSH and SFTP with an end-to-end encrypted credential vault
+Exec=%{dodo_bin}
+Icon=%{dodo_bin}
+Terminal=false
+StartupNotify=true
+StartupWMClass=DodoSSH
+Categories=Network;RemoteAccess;System;
+Keywords=SSH;SFTP;Terminal;Remote;Shell;
+DESKTOP
+
+# One file per size into the hicolor theme, named for the package so the two channels show different
+# entries rather than fighting over one path. The sizes are the ones the icon script draws and its
+# comment argues for; adding one there means adding it here.
+for size in 48 64 128 256; do
+    mkdir -p %{buildroot}%{_datadir}/icons/hicolor/${size}x${size}/apps
+    install -m 0644 %{dodo_icons}/dodossh-${size}.png \
+        %{buildroot}%{_datadir}/icons/hicolor/${size}x${size}/apps/%{dodo_bin}.png
+done
+
+# Installed rather than listed straight out of the source tree. `%license` is a %doc-style marker and
+# resolves its argument against the build directory, which this spec does not have — there is no
+# %prep and no %build, because the payload arrives already published. Putting the file where it
+# belongs first and marking the installed path second is the form that works with neither.
+mkdir -p %{buildroot}%{_licensedir}/%{name}
+install -m 0644 %{dodo_licence} %{buildroot}%{_licensedir}/%{name}/LICENSE
+
+# Modern rpm on Fedora fires file triggers that do both of these, so on the distribution this was
+# measured against they are redundant. They are here for the ones that do not, and every line ends in
+# `|| :` so that a host without the tool installed gets a package that installs rather than a
+# scriptlet failure at the end of a 130 MB transaction.
+%post
+/usr/bin/update-desktop-database %{_datadir}/applications &>/dev/null || :
+/usr/bin/gtk-update-icon-cache -qtf %{_datadir}/icons/hicolor &>/dev/null || :
+
+%postun
+/usr/bin/update-desktop-database %{_datadir}/applications &>/dev/null || :
+/usr/bin/gtk-update-icon-cache -qtf %{_datadir}/icons/hicolor &>/dev/null || :
+
+%files
+# The whole tree, owned by this package, which is what makes `dnf remove` take all of it. The user's
+# vault cache is not in here and is not touched by an uninstall — ClientPaths puts it under
+# $XDG_DATA_HOME, which is the Linux spelling of the same decision ADR 0013's consequences record for
+# Windows: the install moves, the profile does not, and an uninstall is not a sign-out.
+/opt/%{dodo_dir}
+%{_bindir}/%{dodo_bin}
+%{_datadir}/applications/%{dodo_bin}.desktop
+%{_datadir}/icons/hicolor/*/apps/%{dodo_bin}.png
+%license %{_licensedir}/%{name}/LICENSE
+
+%changelog
+# Deliberately empty. The changelog of record is the git history and the release notes on the forge,
+# and a %changelog generated per build from a version number carries no information that `rpm -q`
+# does not already answer — while a hand-written one is a third place a release has to remember to
+# edit. rpmlint says W: no-changelog and that warning is accepted.