BentoPDF for bau-pm, without third-party hosts (bau-pm BAU-119)

BentoPDF v2.8.8 built from source at its pinned commit with BentoPDF's own
air-gapped build options, every module it would load from a CDN vendored and
checked against vendor.lock, a Content-Security-Policy without a single host,
digital-sign-pdf and timestamp-pdf disabled because both need a third party,
and the hand-off glue on every page: the AGPL source link, the hand-in of a
file from bau-pm through a one-minute cookie into sessionStorage, confirmed by
the tool's reaction, the hand-back of a result from every window, and the
signing tool's flatten switch locked on.

The zero-host gate drives all 117 enabled tool pages in Chromium and fails on
any request to another origin, any CSP violation, a CSP that names a host, and
a disabled id that names no page. Green on this image (3 min 52 s on a private
network), red on the stock upstream image (115 findings) and on a misspelled
id. CI runs it on every push, the release workflow before it pushes.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.dockerignore

@@ -0,0 +1,5 @@
+.git
+.gitea
+node_modules
+*.md
+!README.md

.gitea/workflows/ci.yml

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+# CI - every push to dev and every pull request: the scripts linted, the image
+# built from BentoPDF's pinned commit, and the gate this repository exists for
+# (README, "The gate"): a page may talk to its own origin and to nobody else.
+name: CI
+
+on:
+  push:
+    branches: [dev]
+  pull_request:
+
+jobs:
+  gate:
+    runs-on: ubuntu-latest
+    timeout-minutes: 120
+    steps:
+      - uses: actions/checkout@11d5960a326750d5838078e36cf38b85af677262 # v4.4.0
+
+      # Over stdin: the runner passes the host's Docker socket through, so a
+      # mounted workspace would resolve on the host and be empty.
+      - name: shellcheck
+        run: |
+          for f in scripts/*.sh; do
+            echo "-- $f"
+            docker run --rm -i koalaman/shellcheck:v0.11.0 - < "$f"
+          done
+
+      # npm ci and the Vite build are the slow part, several minutes on the
+      # shared runner; the vendor stage downloads about 60 MB from npm.
+      - name: build the image
+        timeout-minutes: 60
+        run: docker build --build-arg VERSION="ci-${GITHUB_SHA::8}" -t bau-pm-pdf-tools:ci .
+
+      - name: build the gate
+        timeout-minutes: 15
+        run: docker build -f test/Dockerfile -t bau-pm-pdf-tools-gate:ci .
+
+      - name: gate - nothing leaves the origin
+        timeout-minutes: 40
+        run: |
+          net="bau-pm-pdf-tools-ci-${GITHUB_RUN_ID}"
+          docker network create "$net" >/dev/null
+          trap 'docker rm -f -v "$net-app" >/dev/null 2>&1; docker network rm "$net" >/dev/null 2>&1' EXIT
+          docker run -d --name "$net-app" --network "$net" --network-alias pdf-tools bau-pm-pdf-tools:ci >/dev/null
+          for i in $(seq 1 30); do
+            docker run --rm --network "$net" bau-pm-pdf-tools-gate:ci wget -q --spider http://pdf-tools:8080/ && break
+            [ "$i" -eq 30 ] && { echo "the image never answered" >&2; exit 1; }
+            sleep 2
+          done
+          docker run --rm --network "$net" bau-pm-pdf-tools-gate:ci node test/zero-hosts.mjs http://pdf-tools:8080

.gitea/workflows/release.yml

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+# Release - runs on semver tags (vMAJOR.MINOR.BUGFIX, cut on main after a
+# fast-forward from dev): the gates, the image built and checked like in CI,
+# pushed to the registry, and a Gitea release with the CHANGELOG section.
+# Required: secrets REGISTRY_USERNAME, REGISTRY_PASSWORD (instance-wide).
+name: Release
+
+on:
+  push:
+    tags: ['v[0-9]+.[0-9]+.[0-9]+']
+
+env:
+  REGISTRY: ${{ vars.REGISTRY || 'hub.bundespruefstelle.ch' }}
+  IMAGE: bau-pm/pdf-tools
+
+jobs:
+  release:
+    runs-on: ubuntu-latest
+    timeout-minutes: 150
+    steps:
+      # Full history, or the ancestry gate cannot answer and would pass.
+      - uses: actions/checkout@11d5960a326750d5838078e36cf38b85af677262 # v4.4.0
+        with:
+          fetch-depth: 0
+
+      - name: derive version from tag
+        run: echo "VERSION=${GITHUB_REF_NAME#v}" >> "$GITHUB_ENV"
+
+      - name: gate - CHANGELOG has a section for this version
+        run: |
+          if ! grep -q "^## \[$VERSION\]" CHANGELOG.md; then
+            echo "no '## [$VERSION]' section in CHANGELOG.md - cut it from [Unreleased] first" >&2
+            exit 1
+          fi
+
+      - name: gate - the tag is on main
+        run: |
+          git fetch --no-tags origin +refs/heads/main:refs/remotes/origin/main
+          if ! git merge-base --is-ancestor "$GITHUB_SHA" origin/main; then
+            echo "$GITHUB_SHA is not an ancestor of main - fast-forward main before tagging" >&2
+            exit 1
+          fi
+
+      - name: build the image
+        timeout-minutes: 60
+        run: |
+          docker build --build-arg VERSION="v$VERSION" \
+            -t "$REGISTRY/$IMAGE:$VERSION" -t "$REGISTRY/$IMAGE:latest" .
+
+      - name: gate - nothing leaves the origin
+        timeout-minutes: 50
+        run: |
+          docker build -f test/Dockerfile -t bau-pm-pdf-tools-gate:release .
+          net="bau-pm-pdf-tools-release-${GITHUB_RUN_ID}"
+          docker network create "$net" >/dev/null
+          trap 'docker rm -f -v "$net-app" >/dev/null 2>&1; docker network rm "$net" >/dev/null 2>&1' EXIT
+          docker run -d --name "$net-app" --network "$net" --network-alias pdf-tools "$REGISTRY/$IMAGE:$VERSION" >/dev/null
+          for i in $(seq 1 30); do
+            docker run --rm --network "$net" bau-pm-pdf-tools-gate:release wget -q --spider http://pdf-tools:8080/ && break
+            [ "$i" -eq 30 ] && { echo "the image never answered" >&2; exit 1; }
+            sleep 2
+          done
+          docker run --rm --network "$net" bau-pm-pdf-tools-gate:release node test/zero-hosts.mjs http://pdf-tools:8080
+
+      - name: push
+        run: |
+          echo "${{ secrets.REGISTRY_PASSWORD }}" \
+            | docker login "$REGISTRY" -u "${{ secrets.REGISTRY_USERNAME }}" --password-stdin
+          docker push "$REGISTRY/$IMAGE:$VERSION"
+          docker push "$REGISTRY/$IMAGE:latest"
+          echo "digest: $(docker inspect --format '{{index .RepoDigests 0}}' "$REGISTRY/$IMAGE:$VERSION")"
+
+      # Below 1.0.0 a release is a prerelease, derived from the tag.
+      - name: create Gitea release with changelog notes
+        run: |
+          notes="$(awk -v ver="$VERSION" '$0 ~ "^## \\[" ver "\\]" {f=1; next} /^## \[/ {f=0} f' CHANGELOG.md)"
+          payload="$(printf '%s' "$notes" | python3 -c 'import json,os,sys; v=os.environ["VERSION"]; print(json.dumps({"tag_name": "v" + v, "name": "bau-pm-pdf-tools v" + v, "body": sys.stdin.read().strip(), "prerelease": v.split(".")[0] == "0"}))')"
+          curl -sf -X POST \
+            -H "Authorization: token ${{ secrets.GITHUB_TOKEN }}" \
+            -H "Content-Type: application/json" \
+            -d "$payload" \
+            "${GITHUB_API_URL}/repos/${GITHUB_REPOSITORY}/releases" >/dev/null \
+            && echo "Gitea release v$VERSION created" \
+            || echo "release creation skipped (may already exist)"

.gitignore

@@ -0,0 +1,2 @@
+node_modules/
+*.log

.markdownlint.jsonc

@@ -0,0 +1,8 @@
+// markdownlint rules (bau-pm BAU-110), read by scripts/lint-md.sh. Managed by
+// the bau-pm plugin kit (templates/plugin/): change it there, not here.
+{
+  // Markdown is never hard-wrapped here: one paragraph per line.
+  "MD013": false,
+  // Keep a Changelog repeats "### Added" / "### Fixed" under every release.
+  "MD024": { "siblings_only": true }
+}

CHANGELOG.md

@@ -0,0 +1,14 @@
+# Changelog
+
+All notable changes to this project are documented in this file. The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/), and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+### Added
+
+- BentoPDF v2.8.8 built from source at its pinned commit with BentoPDF's air-gapped build options: Simple Mode, German by default, every module served from the image's own `/wasm/`, the CORS proxy off.
+- The CDN modules vendored and checked against `vendor.lock` (PyMuPDF, Ghostscript, CoherentPDF, Tesseract with German, French, Italian and English, the OCR font, the PDF editor's Latin, Arabic and Hebrew fallback fonts). Ghostscript is served as its whole package with `gs.js` and `gs.wasm` linked at its root, because BentoPDF's own loader and PyMuPDF's wrapper expect the two different layouts (upstream's air-gap layout left `pdf-to-docx` with a 404).
+- A Content-Security-Policy without any host, `img-src` included; the build fails if one survives.
+- `digital-sign-pdf` and `timestamp-pdf` disabled: both need a third party by design.
+- The hand-off glue on every page: a source link (AGPL), the hand-in of a file from bau-pm through a one-minute cookie into the tab's `sessionStorage`, confirmed by the tool's own reaction and retried while it has none (BentoPDF attaches its listener late, and its service worker made the glue win that race), the hand-back of a result caught in every window, the viewer's frame included, and waiting for the hand-off's details when a save comes before them, and the signing tool's flatten switch locked on.
+- The zero-host gate (`test/zero-hosts.mjs`) over every tool page, in CI and in the release workflow.

Dockerfile

@@ -0,0 +1,109 @@
+# syntax=docker/dockerfile:1
+#
+# BentoPDF for bau-pm: BentoPDF built from source at a pinned commit with
+# BentoPDF's own air-gapped build options, every module it would otherwise load
+# from a CDN served from this image, and bau-pm's hand-off glue added to every
+# page. Nothing here edits BentoPDF's code: its documented build arguments, its
+# runtime config.json, its generated header file with the hosts taken out, and
+# our files beside its own.
+#
+# The images are upstream's: the builder and the runtime stage are the ones
+# BentoPDF's Dockerfile uses.
+
+ARG BENTOPDF_REF=v2.8.8
+ARG BENTOPDF_COMMIT=f96cd4e5166f3d51393dfe9f3c440b5bb77802f1
+ARG NODE_IMAGE=public.ecr.aws/docker/library/node:20-alpine
+ARG NGINX_IMAGE=quay.io/nginx/nginx-unprivileged:alpine-slim
+
+# --- BentoPDF's source, at the commit the tag must point to ---
+FROM ${NODE_IMAGE} AS source
+ARG BENTOPDF_REF
+ARG BENTOPDF_COMMIT
+RUN apk add --no-cache git
+RUN git clone --quiet --depth 1 --branch "${BENTOPDF_REF}" https://github.com/alam00000/bentopdf.git /src \
+ && actual=$(git -C /src rev-parse HEAD) \
+ && if [ "$actual" != "${BENTOPDF_COMMIT}" ]; then \
+      echo "BentoPDF ${BENTOPDF_REF} is ${actual}, expected ${BENTOPDF_COMMIT}" >&2; exit 1; \
+    fi \
+ && rm -rf /src/.git
+
+# --- The CDN modules, packed from npm and checked against vendor.lock ---
+FROM ${NODE_IMAGE} AS vendor
+COPY --from=source /src/bentopdf-airgap-bundle /src/bentopdf-airgap-bundle
+COPY vendor.lock /vendor.lock
+COPY --chmod=755 scripts/vendor.sh /usr/local/bin/vendor.sh
+RUN vendor.sh /src /vendor.lock /wasm
+
+# --- BentoPDF's build, as BentoPDF's Dockerfile runs it ---
+FROM ${NODE_IMAGE} AS builder
+WORKDIR /app
+COPY --from=source /src/package.json /src/package-lock.json ./
+COPY --from=source /src/vendor ./vendor
+ENV HUSKY=0
+RUN npm config set fetch-retries 5 \
+ && npm config set fetch-retry-mintimeout 60000 \
+ && npm config set fetch-retry-maxtimeout 300000 \
+ && npm config set fetch-timeout 600000 \
+ && npm ci
+COPY --from=source /src ./
+
+# The air-gapped build: every module path is this image's own, the CORS proxy
+# (used only by the X.509 tool, which config.json disables) is switched off,
+# and Simple Mode drops the marketing pages. Relative paths, so the image does
+# not know the hostname it will be served under.
+ENV SIMPLE_MODE=true \
+    DISABLE_GITHUB_STARS=true \
+    COMPRESSION_MODE=all \
+    BASE_URL= \
+    VITE_DEFAULT_LANGUAGE=de \
+    VITE_CORS_PROXY_URL= \
+    VITE_WASM_PYMUPDF_URL=/wasm/pymupdf/ \
+    VITE_WASM_GS_URL=/wasm/gs/ \
+    VITE_WASM_CPDF_URL=/wasm/cpdf/ \
+    VITE_TESSERACT_WORKER_URL=/wasm/ocr/worker.min.js \
+    VITE_TESSERACT_CORE_URL=/wasm/ocr/core \
+    VITE_TESSERACT_LANG_URL=/wasm/ocr/lang-data \
+    VITE_TESSERACT_AVAILABLE_LANGUAGES=deu,fra,ita,eng \
+    VITE_OCR_FONT_BASE_URL=/wasm/ocr/fonts \
+    VITE_EMBEDPDF_FONTS_URL=/wasm/embedpdf \
+    NODE_OPTIONS=--max-old-space-size=3072
+RUN npm run build
+
+COPY --chmod=755 scripts/finish.sh /usr/local/bin/finish.sh
+RUN finish.sh /app
+
+# --- Upstream's runtime stage, with our files beside BentoPDF's ---
+FROM ${NGINX_IMAGE}
+ARG BENTOPDF_REF
+ARG SOURCE_URL=https://src.bundespruefstelle.ch/magdev/bau-pm-pdf-tools
+ARG VERSION=dev
+
+LABEL org.opencontainers.image.title="bau-pm-pdf-tools" \
+      org.opencontainers.image.description="BentoPDF ${BENTOPDF_REF} for bau-pm, without third-party hosts" \
+      org.opencontainers.image.source="${SOURCE_URL}" \
+      org.opencontainers.image.version="${VERSION}" \
+      org.opencontainers.image.licenses="AGPL-3.0-only"
+
+ENV DISABLE_IPV6=false \
+    PORT=8080
+
+USER root
+RUN apk upgrade --no-cache
+USER nginx
+
+COPY --chown=nginx:nginx --from=builder /app/dist /usr/share/nginx/html
+COPY --chown=nginx:nginx --from=builder /app/nginx.conf /etc/nginx/nginx.conf
+COPY --chown=nginx:nginx --from=builder /app/security-headers.conf /etc/nginx/security-headers.conf
+COPY --chown=nginx:nginx --from=builder /app/security-headers-docs.conf /etc/nginx/security-headers-docs.conf
+COPY --chown=nginx:nginx --chmod=755 --from=builder /app/nginx-ipv6.sh /docker-entrypoint.d/99-disable-ipv6.sh
+COPY --chown=nginx:nginx --chmod=755 --from=builder /app/nginx-noindex.sh /docker-entrypoint.d/98-noindex.sh
+COPY --chown=nginx:nginx --from=vendor /wasm /usr/share/nginx/html/wasm
+COPY --chown=nginx:nginx config/config.json /usr/share/nginx/html/config.json
+COPY --chown=nginx:nginx glue/ /usr/share/nginx/html/bau-pm/
+RUN sed -i "s#__BAU_PM_SOURCE_URL__#${SOURCE_URL}/src/tag/${VERSION}#" /usr/share/nginx/html/bau-pm/handoff.js \
+ && grep -q "${SOURCE_URL}" /usr/share/nginx/html/bau-pm/handoff.js \
+ && mkdir -p /etc/nginx/tmp
+
+EXPOSE 8080
+HEALTHCHECK --interval=30s --timeout=5s --retries=3 CMD wget --spider -q http://127.0.0.1:8080/ || exit 1
+CMD ["nginx", "-g", "daemon off;"]

LICENSE

@@ -0,0 +1,661 @@
+                    GNU AFFERO GENERAL PUBLIC LICENSE
+                       Version 3, 19 November 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
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+software and other kinds of works, specifically designed to ensure
+cooperation with the community in the case of network server software.
+
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+to take away your freedom to share and change the works.  By contrast,
+our General Public Licenses are intended to guarantee your freedom to
+share and change all versions of a program--to make sure it remains free
+software for all its users.
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+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
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+<https://www.gnu.org/licenses/>.

README.md

@@ -0,0 +1,57 @@
+# bau-pm-pdf-tools
+
+[BentoPDF](https://github.com/alam00000/bentopdf) for [bau-pm](https://src.bundespruefstelle.ch/magdev/bau-pm): about 120 PDF tools (edit, annotate, sign, fill forms, organise, merge, split, compress, convert, OCR) that run entirely in the browser, packaged so that a page of it talks to its own origin and to **nobody else**, plus the glue that hands a PDF from bau-pm into a tool and the result back.
+
+This repository is public on purpose. BentoPDF is AGPL-3.0, and this is a modified version served over a network, so its source is offered to every user: each page of the running image links here, to the tag it was built from.
+
+## What is in the image
+
+- **BentoPDF built from source at a pinned commit** (`BENTOPDF_REF` and `BENTOPDF_COMMIT` in the `Dockerfile`; the build fails if the tag points elsewhere), with BentoPDF's own air-gapped build options: Simple Mode, German as the default language, every module path pointing at this image (`/wasm/...`), the CORS proxy switched off.
+- **Every module BentoPDF would otherwise load from a CDN**, served from `/wasm/`: PyMuPDF and Ghostscript from BentoPDF's own repository at that commit, CoherentPDF, Tesseract with `deu`, `fra`, `ita` and `eng`, the OCR text-layer font and the PDF editor's Latin, Arabic and Hebrew fallback fonts from npm. `scripts/vendor.sh` packs each one and refuses the build when the registry's integrity differs from `vendor.lock`. The editor's CJK fonts (30 to 42 MB each) are left out; a document that needs them asks this server and gets a 404, never a third party.
+- **A Content-Security-Policy without a single host**: BentoPDF's generated header file with every `http(s):` source taken out, `img-src` included (`scripts/finish.sh`, which fails the build if any host survives).
+- **Two tools disabled** in `config/config.json`, because they cannot work without a third party: `digital-sign-pdf` (X.509 signing fetches certificate chains through a CORS proxy) and `timestamp-pdf` (an RFC 3161 timestamp needs an external timestamp authority).
+- **The glue**, `glue/handoff.js`, added to every HTML page by `scripts/finish.sh`: the source link, the hand-in of a file from bau-pm, the hand-back of a result, and the signing tool's flatten switch locked on. See the file's header for how each works.
+
+Nothing of BentoPDF's code is edited: its documented build arguments, its runtime `config.json`, its generated header file with fewer hosts, and our files beside its own.
+
+## How bau-pm uses it
+
+bau-pm runs the image as its `pdf-tools` service on an origin of its own (`PDF_TOOLS_ADDRESS`, e.g. `pdf.example.ch`), behind its Caddy, which asks Redmine before serving any page, so only logged-in users get in. The design, the login gate and the hand-off protocol are bau-pm's (`PLAN.md` §2.50 there); this image only needs to be reachable on port 8080. It is static nginx: about 3 MB of memory, and it writes nothing but its temp directories, so it runs with a read-only root and three tmpfs mounts owned by uid 101 (see bau-pm's `compose.yaml`).
+
+## The gate
+
+`test/zero-hosts.mjs` drives every tool page linked from the German overview in a phone-sized Chromium: it gives each a probe file its input accepts, presses its main button, and fails on any request to another origin and on any CSP violation (a blocked request is a tool that tried to call out). It also fails when the CSP names a host, and when an id in `config.json` does not name a real page or its page still offers the tool. CI runs it on every push (`.gitea/workflows/ci.yml`), and the release workflow runs it again on the image it is about to push.
+
+It has teeth: fed the stock upstream image it fails with 115 findings (PyMuPDF, Pyodide and CoherentPDF from jsdelivr), and fed a misspelled disabled id it fails with "no page".
+
+Locally (bridged containers need no internet for it):
+
+```sh
+docker build -t bau-pm-pdf-tools:ci .
+docker build -f test/Dockerfile -t bau-pm-pdf-tools-gate:ci .
+docker network create pdf-gate
+docker run -d --name pdf-gate-app --network pdf-gate --network-alias pdf-tools bau-pm-pdf-tools:ci
+docker run --rm --network pdf-gate bau-pm-pdf-tools-gate:ci node test/zero-hosts.mjs http://pdf-tools:8080
+docker rm -f -v pdf-gate-app && docker network rm pdf-gate
+```
+
+## Bumping BentoPDF
+
+1. Set `BENTOPDF_REF` and `BENTOPDF_COMMIT` in the `Dockerfile` to the new tag and its commit.
+2. Compare the module versions BentoPDF expects (`package-lock.json` for Tesseract, `.env.production` and `src/js/utils/wasm-provider.ts` for PyMuPDF, Ghostscript and CoherentPDF, `src/js/config/editor-fonts.ts` for the editor's fonts, `src/js/config/font-mappings.ts` for the OCR font) with `vendor.lock` and `scripts/vendor.sh`, and update both together: a new version needs its integrity from the registry (`npm view <pkg>@<version> dist.integrity`).
+3. Read the diff of `scripts/generate-security-headers.mjs`, `nginx.conf` and `scripts/prepare-airgap.sh` upstream: a new directive, a new CDN or a new module layout is where a bump can break the zero-host promise.
+4. Build, run the gate, and check the two disabled tools are still the only ones that need a third party.
+5. Note the bump in `CHANGELOG.md`, release, and pin the new tag in bau-pm (`PDF_TOOLS_VERSION`).
+
+## Known upstream issues (BentoPDF v2.8.8)
+
+Measured on 2026-10-10 against the stock image as much as against this one, so they are upstream behaviour, not this packaging:
+
+- **A signature drawn in the signing tool cannot be saved.** With real touch input, pdf.js's serialisation fails (`Cannot read properties of null (reading 'serialize')`): with *Flatten PDF* on the export fails visibly, with it off pdf.js silently saves the unsigned original. A typed signature saves.
+- **Flattening drops a signature on some PDFs.** BentoPDF's `flattenAnnotations` removes any annotation without an appearance stream, and on a PDF rendered by rbpdf/TCPDF (bau_pm_preflight's Vorausmass sheet) the typed signature comes back without one. On a PDF pdf-lib has re-saved once, it is kept. With flatten off, the signature stays as an annotation.
+
+bau_pm_preflight's tablet sign-off (its PRE-43) waits on these; see its `PLAN.md` §3.22.
+
+## Licence
+
+AGPL-3.0, as BentoPDF (`LICENSE`). The vendored modules keep their own licences; see `THIRD-PARTY.md`.

THIRD-PARTY.md

@@ -0,0 +1,16 @@
+# Third-party components in the image
+
+The image contains BentoPDF and the modules below, unmodified, at the versions listed; the licences are as each package declares it on npm (read 2026-10-10). The source links are the corresponding source of what the image serves under `/wasm/`.
+
+| Component | Version | Licence | Source |
+| --- | --- | --- | --- |
+| BentoPDF | v2.8.8 (`f96cd4e5166f3d51393dfe9f3c440b5bb77802f1`) | AGPL-3.0 (or BentoPDF's commercial licence) | <https://github.com/alam00000/bentopdf/tree/v2.8.8> |
+| PyMuPDF (WASM, `@bentopdf/pymupdf-wasm`) | 0.11.16 | AGPL-3.0-only | <https://github.com/alam00000/bentopdf-pymupdf-wasm>; the tarball from BentoPDF's `bentopdf-airgap-bundle/` at the commit above |
+| Ghostscript (WASM, `@bentopdf/gs-wasm`) | 0.1.1 | AGPL-3.0-only | <https://github.com/alam00000/bentopdf-gs-wasm>; the tarball from BentoPDF's `bentopdf-airgap-bundle/` at the commit above |
+| CoherentPDF (`coherentpdf`) | 2.5.5 | AGPL-3.0-or-later | <https://www.npmjs.com/package/coherentpdf/v/2.5.5>, <https://github.com/coherentgraphics/coherentpdf.js> |
+| Tesseract.js (`tesseract.js`, `tesseract.js-core`) | 7.0.0 | Apache-2.0 | <https://github.com/naptha/tesseract.js>, <https://github.com/naptha/tesseract.js-core> |
+| Tesseract language data (`@tesseract.js-data/deu`, `fra`, `ita`, `eng`) | 1.0.0 (`4.0.0_best_int`) | MIT (as published on npm) | <https://github.com/naptha/tessdata> |
+| Noto Sans (OCR text layer) | noto-fonts `ffebf8c1ee449e544955a7e813c54f9b73848eac` | OFL-1.1 | <https://github.com/googlefonts/noto-fonts> |
+| EmbedPDF fonts (`@embedpdf/fonts-latin`, `-arabic`, `-hebrew`) | 1.0.0 | OFL-1.1 | <https://github.com/embedpdf/embed-pdf-viewer> |
+
+The npm tarballs are checked against the integrity hashes in `vendor.lock`, the Noto Sans file against the SHA-256 in `scripts/vendor.sh`.

config/config.json

@@ -0,0 +1,3 @@
+{
+  "disabledTools": ["digital-sign-pdf", "timestamp-pdf"]
+}

glue/handoff.js

@@ -0,0 +1,375 @@
+/* bau-pm-pdf-tools - the hand-off between bau-pm and BentoPDF's tools.
+ *
+ * Loaded by every page of this image, the PDF.js viewers' pages inside the
+ * tools included, as a classic script in <head>, so it runs before BentoPDF's
+ * own modules. It does four things:
+ *
+ * 1. A link to this image's source on every page, because the AGPL asks the
+ *    source of a modified version served over a network to be offered
+ *    prominently, and BentoPDF's Simple Mode hides its own footer.
+ * 2. The hand-in. bau-pm's entry leaves the hand-off token in a one-minute
+ *    cookie; it moves into sessionStorage (this tab only, gone with it), the
+ *    cookie is deleted at once, and the file is fetched from
+ *    /bau-pm/handoff/file and given to the tool's file input, the way a user
+ *    picking it would. Never in a URL: a token in a redirect's Location
+ *    header lands in every access log on the way.
+ * 3. The hand-back. Every BentoPDF tool saves its result the same way: a blob
+ *    URL on an <a download>, click(), revoke. While a hand-off is active and
+ *    may be saved, that click is caught - in the top page and in the viewer's
+ *    frame - and offered back to bau-pm instead of the downloads folder. The
+ *    blob is read inside click(), because the next line revokes its URL.
+ * 4. For the signing tool, BentoPDF's "flatten" switched on and locked, so a
+ *    signature becomes part of the page and cannot be moved later.
+ *
+ * Nothing here talks to anything but this origin. The words of the hand-off
+ * come from bau-pm in the user's language; only the source link has its own.
+ */
+(function () {
+  'use strict';
+
+  var KEY = 'bau-pm-handoff';
+  var COOKIE = '__Host-bau_pm_handoff';
+  var API = '/bau-pm/handoff';
+  var SOURCE_URL = '__BAU_PM_SOURCE_URL__';
+  var isTop = window.top === window;
+
+  // --- shared state --------------------------------------------------------
+
+  function readState() {
+    try { return JSON.parse(window.sessionStorage.getItem(KEY) || 'null'); } catch (e) { return null; }
+  }
+
+  function writeState(state) {
+    try {
+      if (state) { window.sessionStorage.setItem(KEY, JSON.stringify(state)); } else { window.sessionStorage.removeItem(KEY); }
+    } catch (e) { /* storage blocked: the hand-off lasts this page only */ }
+  }
+
+  function ready(fn) {
+    if (document.readyState !== 'loading') { fn(); } else { document.addEventListener('DOMContentLoaded', fn); }
+  }
+
+  function fill(text, values) {
+    return String(text || '').replace(/%\{(\w+)\}/g, function (m, key) {
+      return values && values[key] != null ? values[key] : m;
+    });
+  }
+
+  // --- 3. the hand-back, installed first and in every window ---------------
+
+  var nativeClick = HTMLAnchorElement.prototype.click;
+  HTMLAnchorElement.prototype.click = function () {
+    var api = null;
+    try { api = window.top.bauPmHandoff; } catch (e) { api = null; }
+    if (api && api.catches() && this.hasAttribute('download') && /^blob:/.test(this.href)) {
+      // Started synchronously: fetch() resolves the blob URL now, before the
+      // caller's revokeObjectURL on the next line.
+      var name = this.download;
+      var blob = window.fetch(this.href).then(function (r) { return r.blob(); });
+      api.offer(blob, name);
+      return undefined;
+    }
+    return nativeClick.apply(this, arguments);
+  };
+
+  if (!isTop) {
+    signFrame();
+    return;
+  }
+
+  // --- 1. the source link --------------------------------------------------
+
+  var LANG = (window.location.pathname.split('/')[1] || 'en').slice(0, 2);
+  var SOURCE_LABEL = { de: 'Quelltext (AGPL-3.0)', fr: 'Code source (AGPL-3.0)', it: 'Codice sorgente (AGPL-3.0)' }[LANG] ||
+    'Source code (AGPL-3.0)';
+
+  var CSS = [
+    '.bau-pm-source{position:fixed;left:8px;bottom:8px;z-index:2147483000;font:12px/1.4 system-ui,sans-serif;',
+    'color:#d1d5db;background:rgba(17,24,39,.85);padding:2px 8px;border-radius:4px;text-decoration:none}',
+    '.bau-pm-source:hover,.bau-pm-source:focus{color:#fff;text-decoration:underline}',
+    '.bau-pm-bar{position:sticky;top:0;z-index:2147483001;display:flex;gap:12px;align-items:center;',
+    'padding:10px 14px;background:#111827;color:#f9fafb;border-bottom:3px solid #F28E00;font:15px/1.4 system-ui,sans-serif}',
+    '.bau-pm-bar span{flex:1;min-width:0;overflow-wrap:anywhere}',
+    '.bau-pm-bar button,.bau-pm-sheet button,.bau-pm-sheet a{font:inherit;min-height:44px;padding:8px 16px;border-radius:6px;cursor:pointer}',
+    '.bau-pm-bar button{background:transparent;color:#f9fafb;border:1px solid #6b7280}',
+    '.bau-pm-scrim{position:fixed;inset:0;z-index:2147483002;background:rgba(0,0,0,.55);display:flex;align-items:flex-end;justify-content:center}',
+    '.bau-pm-sheet{width:100%;max-width:560px;background:#111827;color:#f9fafb;border-radius:12px 12px 0 0;',
+    'padding:20px;display:flex;flex-direction:column;gap:12px;font:16px/1.4 system-ui,sans-serif;box-sizing:border-box}',
+    '.bau-pm-sheet p{margin:0;overflow-wrap:anywhere}',
+    '.bau-pm-sheet .bau-pm-primary{background:#F28E00;color:#1a1a1a;border:0;font-weight:600}',
+    '.bau-pm-sheet .bau-pm-secondary{background:transparent;color:#f9fafb;border:1px solid #6b7280;text-align:center;text-decoration:none}',
+    '.bau-pm-sheet .bau-pm-error{color:#fca5a5}'
+  ].join('');
+
+  ready(function () {
+    var style = document.createElement('style');
+    style.textContent = CSS;
+    document.head.appendChild(style);
+    var link = document.createElement('a');
+    link.className = 'bau-pm-source';
+    link.href = SOURCE_URL;
+    link.rel = 'noopener';
+    link.target = '_blank';
+    link.textContent = SOURCE_LABEL;
+    document.body.appendChild(link);
+  });
+
+  // --- 2. the hand-in ------------------------------------------------------
+
+  var match = new RegExp('(?:^|;\\s*)' + COOKIE + '=([^;]+)').exec(document.cookie);
+  if (match) {
+    writeState({ token: decodeURIComponent(match[1].replace(/\+/g, ' ')) });
+    document.cookie = COOKIE + '=; Max-Age=0; Path=/; Secure; SameSite=Strict';
+  }
+
+  var state = readState();
+  var meta = null;
+  var receipt = null;
+  var file = null;
+  var settle = null;
+  // Resolves with the meta once it is here, or null when there is none. A
+  // save clicked before that - BentoPDF reloads the page once when its service
+  // worker first takes control, and the glue fetches the meta again - waits
+  // for it instead of slipping through as a plain download.
+  var metaReady = new Promise(function (resolve) { settle = resolve; });
+
+  window.bauPmHandoff = {
+    catches: function () { return meta ? !!meta.writable : !!(state && state.token); },
+    offer: function (blob, name) {
+      metaReady.then(function (ready) {
+        // Not to be saved back: an ordinary download, unless the hand-off
+        // offers none either (the Vorausmass), when the result goes nowhere.
+        if (ready && ready.writable) { offer(blob, name); } else if (!ready || ready.download) { save(blob, name); }
+      });
+    }
+  };
+
+  // A plain download, for a result that is not to be offered back.
+  function save(blobPromise, name) {
+    blobPromise.then(function (blob) {
+      var a = document.createElement('a');
+      a.href = URL.createObjectURL(blob);
+      a.download = name;
+      nativeClick.call(a);
+      window.setTimeout(function () { URL.revokeObjectURL(a.href); }, 1000);
+    });
+  }
+
+  if (!state || !state.token) { settle(null); return; }
+
+  function call(path, options) {
+    options = options || {};
+    options.headers = options.headers || {};
+    options.headers.Authorization = 'Bearer ' + state.token;
+    options.credentials = 'same-origin';
+    options.cache = 'no-store';
+    return window.fetch(API + path, options);
+  }
+
+  function end() {
+    writeState(null);
+    state = null;
+    meta = null;
+    settle(null);
+    var bar = document.querySelector('.bau-pm-bar');
+    if (bar) { bar.remove(); }
+  }
+
+  call('/meta').then(function (response) {
+    if (!response.ok) { throw new Error(String(response.status)); }
+    return response.json();
+  }).then(function (data) {
+    meta = data;
+    settle(data);
+    return call('/file');
+  }).then(function (response) {
+    if (!response.ok) { throw new Error(String(response.status)); }
+    receipt = response.headers.get('X-Bau-Pm-Receipt');
+    return response.blob();
+  }).then(function (blob) {
+    file = new File([blob], meta.filename, { type: 'application/pdf' });
+    ready(function () { banner(); feed(); lockFlatten(); });
+  }).catch(function () {
+    // An expired or foreign token, or a file that is gone: nothing to hand
+    // over, and nothing to say that the gate's own page would not say better.
+    end();
+  });
+
+  function banner() {
+    var bar = document.createElement('div');
+    bar.className = 'bau-pm-bar';
+    bar.setAttribute('role', 'status');
+    var text = document.createElement('span');
+    var values = { filename: meta.filename, title: meta.title };
+    text.textContent = fill(meta.strings.banner, values) +
+      (document.querySelector('input[type=file]') ? '' : ' - ' + meta.strings.pick);
+    var close = document.createElement('button');
+    close.type = 'button';
+    close.textContent = meta.strings.dismiss;
+    close.addEventListener('click', end);
+    bar.appendChild(text);
+    bar.appendChild(close);
+    document.body.insertBefore(bar, document.body.firstChild);
+  }
+
+  // The tool's own input, once per page and only while it is empty: picking
+  // another file by hand always wins.
+  //
+  // After the page's load event, and confirmed: BentoPDF attaches a tool's
+  // change listener from a module it imports after load, so a change
+  // dispatched too early reaches nobody - which is what happened once its
+  // service worker served the page from cache and this file's own fetches
+  // won the race. So the feed watches for the tool's reaction (new nodes in
+  // the page that are not ours) and dispatches again if there is none, a few
+  // times at most, with time enough between tries that a slow tool is not
+  // handed the file twice.
+  function feed() {
+    var tries = 0;
+    function ours(node) {
+      var el = node.nodeType === 1 ? node : node.parentElement;
+      return !!(el && el.closest && el.closest('.bau-pm-bar, .bau-pm-source, .bau-pm-scrim'));
+    }
+    function attempt() {
+      var input = document.querySelector('input[type=file]');
+      if (!input || !/pdf/i.test(input.accept || 'pdf')) {
+        tries += 1;
+        if (tries < 60) { window.setTimeout(attempt, 250); }
+        return;
+      }
+      if (input.files && input.files.length && input.dataset.bauPmFed !== '1') { return; }
+      var transfer = new DataTransfer();
+      transfer.items.add(file);
+      input.files = transfer.files;
+      input.dataset.bauPmFed = '1';
+      var reacted = false;
+      var observer = new MutationObserver(function (records) {
+        if (records.some(function (r) { return !ours(r.target); })) { reacted = true; observer.disconnect(); }
+      });
+      observer.observe(document.body, { childList: true, subtree: true });
+      input.dispatchEvent(new Event('change', { bubbles: true }));
+      window.setTimeout(function () {
+        observer.disconnect();
+        tries += 1;
+        if (!reacted && tries < 5) { attempt(); }
+      }, 2000);
+    }
+    if (document.readyState === 'complete') { window.setTimeout(attempt, 300); } else {
+      window.addEventListener('load', function () { window.setTimeout(attempt, 300); });
+    }
+  }
+
+  // --- 4. the signing tool -------------------------------------------------
+
+  function lockFlatten() {
+    if (meta.tool !== 'sign-pdf') { return; }
+    var lock = function () {
+      var toggle = document.getElementById('flatten-signature-toggle');
+      if (!toggle || toggle.dataset.bauPmLocked) { return; }
+      toggle.checked = true;
+      toggle.dispatchEvent(new Event('change', { bubbles: true }));
+      toggle.disabled = true;
+      toggle.dataset.bauPmLocked = '1';
+      var row = toggle.closest('label') || toggle.parentElement;
+      if (row) { row.style.display = 'none'; }
+    };
+    lock();
+    new MutationObserver(lock).observe(document.body, { childList: true, subtree: true });
+  }
+
+  // Inside the viewer's frame of the signing tool: open on the last page,
+  // where the sheet's signature lines are.
+  function signFrame() {
+    var path = null;
+    try { path = window.top.bauPmHandoff && readState() ? window.top.location.pathname : null; } catch (e) { path = null; }
+    if (!path || !/\/sign-pdf(\.html)?$/.test(path)) { return; }
+    var tries = 0;
+    (function attempt() {
+      var app = window.PDFViewerApplication;
+      if (app && app.pdfDocument && app.pagesCount) {
+        app.page = app.pagesCount;
+        return;
+      }
+      tries += 1;
+      if (tries < 80) { window.setTimeout(attempt, 250); }
+    })();
+  }
+
+  // --- 3. the hand-back's sheet --------------------------------------------
+
+  function button(label, kind) {
+    var b = document.createElement('button');
+    b.type = 'button';
+    b.className = kind;
+    b.textContent = label;
+    return b;
+  }
+
+  function offer(blobPromise, name) {
+    var values = { title: meta.title, filename: name };
+    var scrim = document.createElement('div');
+    scrim.className = 'bau-pm-scrim';
+    var sheet = document.createElement('div');
+    sheet.className = 'bau-pm-sheet';
+    sheet.setAttribute('role', 'dialog');
+    sheet.setAttribute('aria-modal', 'true');
+    var message = document.createElement('p');
+    message.textContent = name;
+    var save = button(fill(meta.strings.save, values), 'bau-pm-primary');
+    sheet.appendChild(message);
+    sheet.appendChild(save);
+
+    if (meta.download) {
+      var download = button(meta.strings.download, 'bau-pm-secondary');
+      download.addEventListener('click', function () {
+        save(blobPromise, name);
+        scrim.remove();
+      });
+      sheet.appendChild(download);
+    }
+
+    var close = button(meta.strings.dismiss, 'bau-pm-secondary');
+    close.addEventListener('click', function () { scrim.remove(); });
+    sheet.appendChild(close);
+
+    save.addEventListener('click', function () {
+      save.disabled = true;
+      save.textContent = meta.strings.saving;
+      blobPromise.then(function (blob) {
+        return call('/file', {
+          method: 'POST',
+          body: blob,
+          headers: { 'Content-Type': 'application/pdf', 'X-Bau-Pm-Receipt': receipt || '' }
+        });
+      }).then(function (response) {
+        return response.json().then(function (body) { return { ok: response.ok, body: body }; });
+      }).then(function (result) {
+        if (!result.ok) { throw new Error(result.body.error || ''); }
+        if (result.body.next_url) {
+          writeState(null);
+          window.location.assign(result.body.next_url);
+          return;
+        }
+        message.textContent = result.body.notice || meta.strings.saved;
+        save.remove();
+        if (result.body.back_url) {
+          var back = document.createElement('a');
+          back.className = 'bau-pm-primary';
+          back.href = result.body.back_url;
+          back.textContent = fill(meta.strings.back, values);
+          back.style.textAlign = 'center';
+          back.style.textDecoration = 'none';
+          sheet.insertBefore(back, sheet.children[1] || null);
+        }
+      }).catch(function (error) {
+        message.className = 'bau-pm-error';
+        message.textContent = fill(meta.strings.failed, { error: error.message });
+        save.disabled = false;
+        save.textContent = meta.strings.retry;
+      });
+    });
+
+    scrim.appendChild(sheet);
+    document.body.appendChild(scrim);
+    save.focus();
+  }
+})();

scripts/finish.sh

@@ -0,0 +1,45 @@
+#!/bin/sh
+# What this repository adds to BentoPDF's finished build, run in the
+# Dockerfile's builder stage after `npm run build`:
+#
+#   finish.sh <app-dir>
+#
+#   1. a <script src="/bau-pm/handoff.js"> in every HTML page, the PDF.js
+#      viewers' pages included (the sign tool saves from inside one of them);
+#   2. the precompressed copies of those pages regenerated, because nginx's
+#      gzip_static would otherwise serve the old page without the tag;
+#   3. every host taken out of the generated Content-Security-Policy, so the
+#      pages may load from their own origin and from nowhere else.
+#
+# Each step checks its own result and fails the build when it did not happen.
+set -eu
+
+app=$1
+dist=$app/dist
+tag='<script src="/bau-pm/handoff.js"></script>'
+
+pages=$(find "$dist" -name '*.html' | wc -l)
+[ "$pages" -gt 100 ] || { echo "finish: only $pages pages in $dist" >&2; exit 1; }
+
+find "$dist" -name '*.html' | while read -r page; do
+  grep -q '</head>' "$page" || { echo "finish: $page has no </head>" >&2; exit 1; }
+  sed -i "s#</head>#$tag</head>#" "$page"
+  rm -f "$page.gz" "$page.br"
+  gzip -9 -k -n "$page"
+done
+# find -exec rather than grep --include, which busybox's grep does not know.
+tagged=$(find "$dist" -name '*.html' -exec grep -lF "$tag" {} + | wc -l)
+[ "$tagged" -eq "$pages" ] || { echo "finish: $tagged of $pages pages carry the tag" >&2; exit 1; }
+stale=$(find "$dist" -name '*.html.br' | wc -l)
+[ "$stale" -eq 0 ] || { echo "finish: $stale brotli copies left" >&2; exit 1; }
+
+for conf in security-headers.conf security-headers-docs.conf; do
+  sed -E -i 's# https?:(//[^ ;"]*)?##g' "$app/$conf"
+  if grep -Eq 'https?:' "$app/$conf"; then
+    echo "finish: $conf still names a host:" >&2
+    grep -Eo 'https?:[^ ;"]*' "$app/$conf" >&2
+    exit 1
+  fi
+done
+
+echo "finish: $tagged pages tagged, CSP without hosts"

scripts/vendor.sh

@@ -0,0 +1,101 @@
+#!/bin/sh
+# Lays out every module BentoPDF would otherwise fetch from a CDN under one
+# directory, in the layout BentoPDF's own air-gap setup produces
+# (scripts/prepare-airgap.sh upstream, its generated setup.sh). Runs in the
+# Dockerfile's vendor stage.
+#
+#   vendor.sh <bentopdf-source> <vendor.lock> <out-dir>
+#
+# Every package comes through `npm pack --json`, which verifies the tarball
+# against the registry; this script then compares that integrity with the one
+# committed in vendor.lock and fails the build on any difference, so a package
+# cannot change under a pinned version unnoticed. A missing input fails too:
+# nothing here skips.
+set -eu
+
+src=$1
+lock=$2
+out=$3
+
+OCR_FONT_URL=https://rawcdn.githack.com/googlefonts/noto-fonts/ffebf8c1ee449e544955a7e813c54f9b73848eac/hinted/ttf/NotoSans/NotoSans-Regular.ttf
+OCR_FONT_SHA256=b85c38ecea8a7cfb39c24e395a4007474fa5a4fc864f6ee33309eb4948d232d5
+
+work=$(mktemp -d)
+mkdir -p "$out/pymupdf" "$out/gs" "$out/cpdf" "$out/ocr/core" "$out/ocr/lang-data" \
+  "$out/ocr/fonts" "$out/embedpdf"
+
+# Packs one spec into $work and checks it against the lock. Prints the tarball.
+# Always called as an assignment (t=$(pack ...)): an exit inside a command
+# substitution only ends the subshell, and only an assignment hands its status
+# to `set -e`.
+pack() {
+  spec=$1
+  want=$(awk -v s="$spec" '$1 == s { print $2 }' "$lock")
+  [ -n "$want" ] || { echo "vendor: $spec is not in $lock" >&2; exit 1; }
+  json=$(cd "$work" && npm pack --json --silent "$spec")
+  got=$(printf '%s' "$json" | node -e 'let s="";process.stdin.on("data",d=>s+=d).on("end",()=>{const p=JSON.parse(s)[0];process.stdout.write(p.integrity+"\t"+p.filename)})')
+  [ "${got%%	*}" = "$want" ] || {
+    echo "vendor: $spec integrity ${got%%	*} differs from the lock's $want" >&2
+    exit 1
+  }
+  echo "$work/${got#*	}"
+}
+
+# Unpacks a tarball's package/<sub> into a directory.
+unpack() {
+  tarball=$1 sub=$2 dest=$3
+  tmp=$(mktemp -d)
+  tar -xzf "$tarball" -C "$tmp"
+  [ -e "$tmp/package/$sub" ] || { echo "vendor: $tarball has no package/$sub" >&2; exit 1; }
+  cp -R "$tmp/package/$sub"/. "$dest"/
+  rm -rf "$tmp"
+}
+
+# PyMuPDF and Ghostscript ship inside BentoPDF's repository, at the pinned commit.
+set -- "$src"/bentopdf-airgap-bundle/bentopdf-pymupdf-wasm-*.tgz
+[ -f "$1" ] || { echo "vendor: no PyMuPDF tarball in $src/bentopdf-airgap-bundle" >&2; exit 1; }
+unpack "$1" . "$out/pymupdf"
+set -- "$src"/bentopdf-airgap-bundle/bentopdf-gs-wasm-*.tgz
+[ -f "$1" ] || { echo "vendor: no Ghostscript tarball in $src/bentopdf-airgap-bundle" >&2; exit 1; }
+# Two loaders read this one directory: BentoPDF's own wants gs.js and gs.wasm
+# at its root (upstream's air-gap layout copies only assets/), PyMuPDF's wrapper
+# wants the package's dist/index.js under it - pdf-to-docx asked for
+# /wasm/gs/dist/index.js and got a 404. The whole package, plus links at the
+# root, serves both from one copy.
+unpack "$1" . "$out/gs"
+ln -s assets/gs.js "$out/gs/gs.js"
+ln -s assets/gs.wasm "$out/gs/gs.wasm"
+
+t=$(pack coherentpdf@2.5.5)
+unpack "$t" dist "$out/cpdf"
+
+tmp=$(mktemp -d)
+t=$(pack tesseract.js@7.0.0)
+tar -xzf "$t" -C "$tmp"
+cp "$tmp/package/dist/worker.min.js" "$out/ocr/worker.min.js"
+rm -rf "$tmp"
+t=$(pack tesseract.js-core@7.0.0)
+unpack "$t" . "$out/ocr/core"
+for lang in deu fra ita eng; do
+  tmp=$(mktemp -d)
+  t=$(pack "@tesseract.js-data/$lang@1.0.0")
+  tar -xzf "$t" -C "$tmp"
+  cp "$tmp/package/4.0.0_best_int/$lang.traineddata.gz" "$out/ocr/lang-data/"
+  rm -rf "$tmp"
+done
+
+wget -q -O "$out/ocr/fonts/NotoSans-Regular.ttf" "$OCR_FONT_URL"
+echo "$OCR_FONT_SHA256  $out/ocr/fonts/NotoSans-Regular.ttf" | sha256sum -c -s || {
+  echo "vendor: the OCR font's checksum differs from $OCR_FONT_SHA256" >&2
+  exit 1
+}
+
+# The PDF editor asks for <base>/fonts-latin@1.0.0/fonts/NotoSans-Regular.ttf.
+for pkg in latin arabic hebrew; do
+  mkdir -p "$out/embedpdf/fonts-$pkg@1.0.0"
+  t=$(pack "@embedpdf/fonts-$pkg@1.0.0")
+  unpack "$t" . "$out/embedpdf/fonts-$pkg@1.0.0"
+done
+
+rm -rf "$work"
+echo "vendor: $(find "$out" -type f | wc -l) files, $(du -sh "$out" | cut -f1)"

test/Dockerfile

@@ -0,0 +1,13 @@
+# The gate's own image (test/zero-hosts.mjs): Chromium and playwright-core,
+# with the test files and the glue baked in, because the CI runner passes the
+# host's Docker socket through and a mounted workspace would be empty.
+FROM public.ecr.aws/docker/library/node:20-alpine
+RUN apk add --no-cache chromium
+WORKDIR /gate
+RUN npm init -y >/dev/null && npm install --no-audit --no-fund --silent playwright-core@1.63.0
+COPY test/ ./test/
+COPY glue/ ./glue/
+RUN node --check glue/handoff.js
+ENV PLAYWRIGHT_CORE=/gate/node_modules/playwright-core/index.mjs \
+    CHROMIUM=/usr/bin/chromium-browser
+CMD ["node", "test/zero-hosts.mjs"]

test/fixtures/probe.pdf

@@ -0,0 +1,30 @@
+%PDF-1.4
+1 0 obj
+<</Type/Catalog/Pages 2 0 R>>
+endobj
+2 0 obj
+<</Type/Pages/Kids[3 0 R]/Count 1>>
+endobj
+3 0 obj
+<</Type/Page/Parent 2 0 R/MediaBox[0 0 595 842]/Contents 4 0 R/Resources<</Font<</F1 5 0 R>>>>>>
+endobj
+4 0 obj
+<</Length 49>>stream
+BT /F1 24 Tf 72 760 Td (Regierapport Probe) Tj ET
+endstream
+endobj
+5 0 obj
+<</Type/Font/Subtype/Type1/BaseFont/Helvetica>>
+endobj
+xref
+0 6
+0000000000 65535 f 
+0000000009 00000 n 
+0000000054 00000 n 
+0000000105 00000 n 
+0000000217 00000 n 
+0000000313 00000 n 
+trailer<</Size 6/Root 1 0 R>>
+startxref
+376
+%%EOF

test/zero-hosts.mjs

@@ -0,0 +1,139 @@
+// The gate this repository exists for (bau-pm PLAN.md §2.50, decision 2): a
+// page of the PDF tools may talk to its own origin and to nobody else.
+//
+//   node test/zero-hosts.mjs <base-url> [chromium-path]
+//
+// 1. The Content-Security-Policy of the start page names no host.
+// 2. Every id config.json disables names a real page, and that page offers
+//    no tool.
+// 3. Every tool page linked from the German overview is opened in a phone-sized
+//    Chromium, given a probe file its input accepts, and its main button
+//    pressed. Any request to another origin fails the gate, and so does any CSP
+//    violation, because a blocked request is a tool that tried to call out.
+//
+// Exits 0 when nothing left the origin, 1 otherwise, 2 when it could not run.
+// Fed the stock upstream image once, it must fail (see README, "The gate").
+import { readFileSync } from 'node:fs';
+import { dirname, join } from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const here = dirname(fileURLToPath(import.meta.url));
+const base = (process.argv[2] || '').replace(/\/$/, '');
+const executablePath = process.argv[3] || process.env.CHROMIUM || '/usr/bin/chromium';
+if (!base) {
+  console.error('usage: zero-hosts.mjs <base-url> [chromium]');
+  process.exit(2);
+}
+
+const { chromium } = await import(process.env.PLAYWRIGHT_CORE || 'playwright-core');
+const origin = new URL(base).origin;
+const probes = {
+  pdf: readFileSync(join(here, 'fixtures/probe.pdf')),
+  png: readFileSync(join(here, 'fixtures/probe.png')),
+};
+const failures = [];
+
+// --- 1. the header -----------------------------------------------------------
+const head = await fetch(`${base}/de/`);
+const csp = head.headers.get('content-security-policy') || '';
+if (!csp) failures.push('start page: no Content-Security-Policy');
+for (const host of csp.match(/https?:[^\s;]*/g) || []) {
+  failures.push(`CSP names a host: ${host}`);
+}
+
+// --- 2. the disabled tools exist, and are disabled ----------------------------
+// A misspelled id in config.json disables nothing and says nothing (found on
+// the first run: `digital-sign` for the page digital-sign-pdf.html), so every
+// id must name a real page, and that page must not offer its tool.
+const config = await (await fetch(`${base}/config.json`)).json();
+const disabled = config.disabledTools || [];
+if (disabled.length === 0) failures.push('config.json disables no tool');
+
+// --- 3. every tool -----------------------------------------------------------
+// The origin counts as secure even over plain HTTP on a CI network, so the
+// page is cross-origin isolated as it is behind TLS in production, and the
+// Office tools run the code they run there rather than a fallback.
+const browser = await chromium.launch({
+  executablePath,
+  args: ['--no-sandbox', `--unsafely-treat-insecure-origin-as-secure=${origin}`],
+});
+const overview = await browser.newPage();
+await overview.goto(`${base}/de/`, { waitUntil: 'networkidle' });
+const tools = [...new Set(await overview.$$eval('a[href$=".html"]', (links) =>
+  links.map((a) => new URL(a.href, location.href)).filter((u) => u.origin === location.origin)
+    .map((u) => u.pathname).filter((p) => p.startsWith('/de/'))))].sort();
+await overview.close();
+for (const id of disabled) {
+  const page = await browser.newPage();
+  const response = await page.goto(`${base}/de/${id}.html`, { waitUntil: 'networkidle' });
+  if (!response || response.status() !== 200) failures.push(`disabled tool ${id}: no page /de/${id}.html`);
+  else if (await page.$('input[type=file]:visible')) failures.push(`disabled tool ${id}: still offers its file input`);
+  if (tools.includes(`/de/${id}.html`)) failures.push(`disabled tool ${id}: still linked from the overview`);
+  await page.close();
+}
+if (tools.length < 50) failures.push(`only ${tools.length} tool pages found on /de/`);
+
+function probeFor(accept) {
+  if (/pdf/i.test(accept)) return { name: 'probe.pdf', mimeType: 'application/pdf', buffer: probes.pdf };
+  if (/image|png|jpe?g/i.test(accept)) return { name: 'probe.png', mimeType: 'image/png', buffer: probes.png };
+  return null;
+}
+
+async function run(path) {
+  const context = await browser.newContext({ viewport: { width: 412, height: 915 }, isMobile: true, hasTouch: true });
+  await context.addInitScript(() => {
+    window.__violations = [];
+    document.addEventListener('securitypolicyviolation', (e) =>
+      window.__violations.push(`${e.violatedDirective} ${e.blockedURI}`));
+  });
+  const page = await context.newPage();
+  const outside = new Set();
+  page.on('request', (request) => {
+    const url = request.url();
+    if (/^(data|blob|about):/.test(url)) return;
+    if (new URL(url).origin !== origin) outside.add(url);
+  });
+  page.on('dialog', (dialog) => dialog.dismiss().catch(() => {}));
+  try {
+    await page.goto(base + path, { waitUntil: 'networkidle', timeout: 30000 });
+    const input = await page.$('input[type=file]');
+    const file = input && probeFor((await input.getAttribute('accept')) || '');
+    if (file) {
+      await input.setInputFiles(file);
+      await page.waitForTimeout(2500);
+      const button = await page.$('#process-btn:visible');
+      if (button) {
+        await button.click({ timeout: 5000 }).catch(() => {});
+        await page.waitForTimeout(5000);
+      }
+    }
+    await page.waitForLoadState('networkidle', { timeout: 15000 }).catch(() => {});
+    const violations = await page.evaluate(() => window.__violations);
+    for (const v of violations) failures.push(`${path}: CSP violation ${v}`);
+  } catch (error) {
+    // A page that cannot be driven is not a leak; it is reported, not failed.
+    console.log(`  note ${path}: ${error.message.split('\n')[0]}`);
+  }
+  for (const url of outside) failures.push(`${path}: request to ${url}`);
+  await context.close();
+  return outside.size;
+}
+
+let done = 0;
+const queue = [...tools];
+await Promise.all(Array.from({ length: 4 }, async () => {
+  while (queue.length) {
+    const path = queue.shift();
+    await run(path);
+    done += 1;
+  }
+}));
+await browser.close();
+
+console.log(`zero-hosts: ${done} tool pages driven against ${origin}, CSP: ${csp ? 'present' : 'missing'}`);
+if (failures.length) {
+  for (const f of [...new Set(failures)]) console.log(`  FAIL ${f}`);
+  console.log(`zero-hosts: ${new Set(failures).size} failure(s)`);
+  process.exit(1);
+}
+console.log('zero-hosts: nothing left the origin');

vendor.lock

@@ -0,0 +1,23 @@
+# Every module BentoPDF would otherwise load from cdn.jsdelivr.net at runtime,
+# pinned by version and by the registry's integrity hash. The Dockerfile's
+# vendor stage packs each one with `npm pack --json` and refuses the build when
+# the integrity it receives differs from the one written here. One line per
+# package: <spec> <integrity>.
+#
+# PyMuPDF (@bentopdf/pymupdf-wasm 0.11.16) and Ghostscript (@bentopdf/gs-wasm
+# 0.1.1) are not listed: BentoPDF ships both tarballs in its own repository
+# (bentopdf-airgap-bundle/), so they come from the pinned commit.
+#
+# Left out on purpose: the CJK fallback fonts of the PDF editor
+# (@embedpdf/fonts-jp, -kr, -sc, -tc, 30 to 42 MB each). A document that needs
+# them asks this server and gets a 404, never a third party.
+coherentpdf@2.5.5 sha512-AAD3RG7lq2n34AtH352sbNDhJ82yfp2vFUp63/+Vu7snAqW0vyvY33XuhZdj6ubZUlFe1DNSSEaYcyc7+jTJ5Q==
+tesseract.js@7.0.0 sha512-exPBkd+z+wM1BuMkx/Bjv43OeLBxhL5kKWsz/9JY+DXcXdiBjiAch0V49QR3oAJqCaL5qURE0vx9Eo+G5YE7mA==
+tesseract.js-core@7.0.0 sha512-WnNH518NzmbSq9zgTPeoF8c+xmilS8rFIl1YKbk/ptuuc7p6cLNELNuPAzcmsYw450ca6bLa8j3t0VAtq435Vw==
+@tesseract.js-data/deu@1.0.0 sha512-3ter1p2gFAiCd5CMC+PodZ9YY2UDomkKj+ytlKeeZqOUmhLx1SDnYPf5zog0g5MBbxYveW+8omI3PUflqHfZ4Q==
+@tesseract.js-data/fra@1.0.0 sha512-pp58gMaoyidoBBLd5y5rnf0WW0Y1994QrGqZrYatITqIU/AReUJMykD+YY3JDgvnmgz7uAx1UmhjjuyEmV8JEA==
+@tesseract.js-data/ita@1.0.0 sha512-Sx19NVYve5VAxEBDL6CWTX+evlvzV+iAS5ejJywcHVsmir/C9Tzw2fExoh97QFc06t48tYZA8VrMobsBzMAEhA==
+@tesseract.js-data/eng@1.0.0 sha512-mbTumm6KQPUHyzTPQaF3ObXYnx0SqqfV2nabqFVQBwD6Kl7PhGSLSzOlfFTWy0P3BjghaSKA2W9GB19Jk+ZcTg==
+@embedpdf/fonts-latin@1.0.0 sha512-LLYysdr8O6sRNzhmW3PbF3AeA8xnqvOi4XLFfIfNlW5uEZ+qsJdcfd78Q78sFJMhlaOAYFMziMMsnOzmx463rA==
+@embedpdf/fonts-arabic@1.0.0 sha512-SnGvQb+LwPZQO2WjjvlmXrJZolJUfLYbLZQSaYUw1vrQyMyJKT4LewvJGG+hZ+Yz2fz7OMIQ+4Gc98mGODZtOg==
+@embedpdf/fonts-hebrew@1.0.0 sha512-5HVAKGL7VqPeTxxADDrSqAFBxfmAXdP8fIqrPwJIKkqdK2643bOer8CqnnpO3/nPoFhkzxhttWMB9BGiqSW62w==