Libellus Potionis

Projects that follow the best practices below can voluntarily self-certify and show that they've achieved an Open Source Security Foundation (OpenSSF) best practices badge.

There is no set of practices that can guarantee that software will never have defects or vulnerabilities; even formal methods can fail if the specifications or assumptions are wrong. Nor is there any set of practices that can guarantee that a project will sustain a healthy and well-functioning development community. However, following best practices can help improve the results of projects. For example, some practices enable multi-person review before release, which can both help find otherwise hard-to-find technical vulnerabilities and help build trust and a desire for repeated interaction among developers from different companies. To earn a badge, all MUST and MUST NOT criteria must be met, all SHOULD criteria must be met OR be unmet with justification, and all SUGGESTED criteria must be met OR unmet (we want them considered at least). If you want to enter justification text as a generic comment, instead of being a rationale that the situation is acceptable, start the text block with '//' followed by a space. Feedback is welcome via the GitHub site as issues or pull requests There is also a mailing list for general discussion.

We gladly provide the information in several locales, however, if there is any conflict or inconsistency between the translations, the English version is the authoritative version.
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These are the Passing level criteria. You can also view the Silver or Gold level criteria.

Baseline Series: Baseline Level 1 Baseline Level 2 Baseline Level 3

        

 Basics 13/13

  • General

    Note that other projects may use the same name.

    Libellus Potionis is a privacy-first, free, open-source, ad-free alcohol-consumption tracker that helps users monitor, pace, and manage their drinking habits entirely offline. It needs no invasive device permissions — no camera, microphone, or location access — and works completely without network connectivity.

    Key features

    • Intelligent logging: predefine custom beverages or use internationally common presets, and log drinks instantly or retroactively with precise timestamp corrections.
    • Concurrent limit tracking: set three simultaneous boundaries — a daily limit (grams of pure alcohol), a rolling 7-day weekly limit (grams), and a maximum number of drinking days per week — with visual progress bars in real time.
    • Blood-alcohol (BAC) estimation: enter your body weight for a live BAC approximation based on the established Widmark formula.
    • Addiction-counseling reports: generate a clear, well-organized two-page PDF report designed for consultations and counseling appointments.
    • Data portability: export your complete dataset as a standard CSV file for external processing (e.g. in LibreOffice Calc), or create secure JSON backups to migrate data between devices.
    • Granular adjustments: customize your "day start" time so late-night drinks count toward the correct evening, and define custom evaluation start dates for clean restarts.

    A comprehensive User's Guide is fully accessible in-app. The app is available on F-Droid.

    Please use SPDX license expression format; examples include "Apache-2.0", "BSD-2-Clause", "BSD-3-Clause", "GPL-2.0+", "LGPL-3.0+", "MIT", and "(BSD-2-Clause OR Ruby)". Do not include single quotes or double quotes.
    If there is more than one language, list them as comma-separated values (spaces optional) and sort them from most to least used. If there is a long list, please list at least the first three most common ones. If there is no language (e.g., this is a documentation-only or test-only project), use the single character "-". Please use a conventional capitalization for each language, e.g., "JavaScript".
    The Common Platform Enumeration (CPE) is a structured naming scheme for information technology systems, software, and packages. It is used in a number of systems and databases when reporting vulnerabilities.

    Libellus Potionis is a privacy-first, offline, ad-free Android app for tracking, pacing, and managing alcohol consumption. It requests no network permission and no camera/microphone/location access; all data stays on the device in the app's private, sandboxed storage, encrypted at rest (AES-256-GCM via the Android Keystore), with an optional biometric lock. It is Free Software under GPL-3.0-or-later, developed openly on Codeberg and distributed through F-Droid. The project is deliberately maintained as a teaching-quality codebase: every source file carries a license header and KDoc, and a release gate (tools/release-check.sh) enforces documentation, version consistency, English-only source, and translation completeness. Quality is guarded by a broad automated test suite (JVM unit tests plus instrumented Room-migration, Compose-UI, and locale tests) and by Android Lint and Kotlin compiler warnings promoted to build-breaking errors.

  • Basic project website content


    The project website MUST succinctly describe what the software does (what problem does it solve?). [description_good]
    This MUST be in language that potential users can understand (e.g., it uses minimal jargon).

    The project's landing page (the repository README, rendered at https://codeberg.org/godisch/potillus) opens with a one-line statement of what the software is — a privacy-first, offline, ad-free alcohol-consumption tracker — and immediately explains the problem it solves: helping users monitor, pace, and manage their drinking habits entirely on-device, with no network access and no invasive permissions. A concise "Key Features" section follows. See README.md: https://codeberg.org/godisch/potillus/src/branch/main/README.md



    The project website MUST provide information on how to: obtain, provide feedback (as bug reports or enhancements), and contribute to the software. [interact]

    The project's landing page (repository README) tells users how to obtain the app (F-Droid and the canonical Codeberg repository), how to provide feedback (a dedicated "Feedback & Contributing" section points to the Codeberg issue tracker for bug reports and enhancement requests, with android@godisch.de as an alternative), and how to contribute (link to CONTRIBUTING.md). See https://codeberg.org/godisch/potillus/src/branch/main/README.md#feedback--contributing



    The information on how to contribute MUST explain the contribution process (e.g., are pull requests used?) (URL required) [contribution]
    We presume that projects on GitHub use issues and pull requests unless otherwise noted. This information can be short, e.g., stating that the project uses pull requests, an issue tracker, or posts to a mailing list (which one?)

    The contribution process is documented in CONTRIBUTING.md, Section 2 "Submitting changes": contributors open an issue to discuss the change, then submit it as a pull request against main on Codeberg (a patch by e-mail is accepted as an alternative); the change must meet the documented architecture, coding, testing, and translation conventions, and is reviewed and merged by the maintainer. URL: https://codeberg.org/godisch/potillus/src/branch/main/CONTRIBUTING.md#2-submitting-changes



    The information on how to contribute SHOULD include the requirements for acceptable contributions (e.g., a reference to any required coding standard). (URL required) [contribution_requirements]

    CONTRIBUTING.md documents the requirements for acceptable contributions. Section 2 ("Submitting changes"), step 3, makes them a merge precondition and points to the relevant sections; Section 4 ("Coding conventions") names the required coding standard — the official Kotlin coding conventions — together with mandatory KDoc and constant/default/enum-persistence rules; Sections 3 (architecture) and 5 (testing) add the remaining acceptance rules. ./gradlew test and tools/release-check.sh must pass. URL: https://codeberg.org/godisch/potillus/src/branch/main/CONTRIBUTING.md#4-coding-conventions


  • FLOSS license


    The software produced by the project MUST be released as FLOSS. [floss_license]
    FLOSS is software released in a way that meets the Open Source Definition or Free Software Definition. Examples of such licenses include the CC0, MIT, BSD 2-clause, BSD 3-clause revised, Apache 2.0, Lesser GNU General Public License (LGPL), and the GNU General Public License (GPL). For our purposes, this means that the license MUST be: The software MAY also be licensed other ways (e.g., "GPLv2 or proprietary" is acceptable).

    The software is released as Free/Libre and Open Source Software under the GNU General Public License v3.0 or later (GPL-3.0-or-later). The full license text is provided in LICENSE.md, the copyright notice in COPYING.md ("either version 3 of the License, or (at your option) any later version"), and the F-Droid metadata declares License: GPL-3.0-or-later. See https://codeberg.org/godisch/potillus/src/branch/main/LICENSE.md



    It is SUGGESTED that any required license(s) for the software produced by the project be approved by the Open Source Initiative (OSI). [floss_license_osi]
    The OSI uses a rigorous approval process to determine which licenses are OSS.

    The project's license, GPL-3.0-or-later, is approved by the Open Source Initiative (OSI) and recognized as free by the FSF. It is the sole license under which the project's own source code is released. Bundled third-party dependencies are additionally under OSI-approved licenses (e.g. Apache-2.0; see COPYING.md), but these are dependencies, not the project's license.



    The project MUST post the license(s) of its results in a standard location in their source repository. (URL required) [license_location]
    One convention is posting the license as a top-level file named LICENSE or COPYING, which MAY be followed by an extension such as ".txt" or ".md". An alternative convention is to have a directory named LICENSES containing license file(s); these files are typically named as their SPDX license identifier followed by an appropriate file extension, as described in the REUSE Specification. Note that this criterion is only a requirement on the source repository. You do NOT need to include the license file when generating something from the source code (such as an executable, package, or container). For example, when generating an R package for the Comprehensive R Archive Network (CRAN), follow standard CRAN practice: if the license is a standard license, use the standard short license specification (to avoid installing yet another copy of the text) and list the LICENSE file in an exclusion file such as .Rbuildignore. Similarly, when creating a Debian package, you may put a link in the copyright file to the license text in /usr/share/common-licenses, and exclude the license file from the created package (e.g., by deleting the file after calling dh_auto_install). We encourage including machine-readable license information in generated formats where practical.

    The project's license is posted in a standard location at the repository root as LICENSE.md (full GPL-3.0-or-later text), which Codeberg/Forgejo auto-detects and displays as the project license; COPYING.md sits alongside it with the copyright notice. URL: https://codeberg.org/godisch/potillus/src/branch/main/LICENSE.md


  • Documentation


    The project MUST provide basic documentation for the software produced by the project. [documentation_basics]
    This documentation must be in some media (such as text or video) that includes: how to install it, how to start it, how to use it (possibly with a tutorial using examples), and how to use it securely (e.g., what to do and what not to do) if that is an appropriate topic for the software. The security documentation need not be long. The project MAY use hypertext links to non-project material as documentation. If the project does not produce software, choose "not applicable" (N/A).

    The project provides basic user documentation. A comprehensive, screen-by-screen User's Guide (android/docs/guide/usersguide.md.in, localized into ~20 languages) explains every screen and feature — Today, Calendar, Statistics, Drinks, and Settings (limits, backup/restore, security, appearance) — and is rendered and displayed inside the app itself (via tools/render-guide.py, shown in DocumentViewerScreen). The README additionally documents the app's purpose, feature set, platform requirements (Android 11+), and how to obtain it. Source: https://codeberg.org/godisch/potillus/src/branch/main/android/docs/guide/usersguide.md.in and https://codeberg.org/godisch/potillus/src/branch/main/README.md



    The project MUST provide reference documentation that describes the external interface (both input and output) of the software produced by the project. [documentation_interface]
    The documentation of an external interface explains to an end-user or developer how to use it. This would include its application program interface (API) if the software has one. If it is a library, document the major classes/types and methods/functions that can be called. If it is a web application, define its URL interface (often its REST interface). If it is a command-line interface, document the parameters and options it supports. In many cases it's best if most of this documentation is automatically generated, so that this documentation stays synchronized with the software as it changes, but this isn't required. The project MAY use hypertext links to non-project material as documentation. Documentation MAY be automatically generated (where practical this is often the best way to do so). Documentation of a REST interface may be generated using Swagger/OpenAPI. Code interface documentation MAY be generated using tools such as JSDoc (JavaScript), ESDoc (JavaScript), pydoc (Python), devtools (R), pkgdown (R), and Doxygen (many). Merely having comments in implementation code is not sufficient to satisfy this criterion; there needs to be an easy way to see the information without reading through all the source code. If the project does not produce software, choose "not applicable" (N/A).

    The software is a GUI Android application; its external interface is the user interface together with the file formats it reads and writes, both documented in the User's Guide as reference material describing inputs and outputs. Inputs: drink logging, limit configuration, and body weight (used to estimate blood alcohol concentration via the Widmark formula). Outputs: the statistics screen (by week/month/year), a CSV export for spreadsheet processing, and a two-page PDF report. The JSON backup interface is documented for both directions — export produces a single JSON file containing all drinks and the complete log, and import offers explicit "replace" and "merge" modes. See https://codeberg.org/godisch/potillus/src/branch/main/android/docs/guide/usersguide.md.in


  • Other


    The project sites (website, repository, and download URLs) MUST support HTTPS using TLS. [sites_https]
    This requires that the project home page URL and the version control repository URL begin with "https:", not "http:". You can get free certificates from Let's Encrypt. Projects MAY implement this criterion using (for example) GitHub pages, GitLab pages, or SourceForge project pages. If you support HTTP, we urge you to redirect the HTTP traffic to HTTPS.

    All project sites support HTTPS with TLS. The project website and source repository are hosted on Codeberg (https://codeberg.org/godisch/potillus), which is HTTPS-only, and the app is distributed through F-Droid (https://f-droid.org/packages/de.godisch.potillus), which also serves exclusively over HTTPS. Both hosts present valid TLS certificates.



    The project MUST have one or more mechanisms for discussion (including proposed changes and issues) that are searchable, allow messages and topics to be addressed by URL, enable new people to participate in some of the discussions, and do not require client-side installation of proprietary software. [discussion]
    Examples of acceptable mechanisms include archived mailing list(s), GitHub issue and pull request discussions, Bugzilla, Mantis, and Trac. Asynchronous discussion mechanisms (like IRC) are acceptable if they meet these criteria; make sure there is a URL-addressable archiving mechanism. Proprietary JavaScript, while discouraged, is permitted.

    Discussion of proposed changes and issues takes place in the project's Codeberg issue tracker and pull requests (https://codeberg.org/godisch/potillus/issues). This mechanism is full-text searchable; every issue, pull request, and comment is addressable by a stable URL; any person with a free Codeberg account can open issues and join the discussion; and it is used entirely through a web browser, requiring no proprietary client-side software (Codeberg runs the FLOSS Forgejo platform).



    The project SHOULD provide documentation in English and be able to accept bug reports and comments about code in English. [english]
    English is currently the lingua franca of computer technology; supporting English increases the number of different potential developers and reviewers worldwide. A project can meet this criterion even if its core developers' primary language is not English.

    All project documentation is provided in English (README.md, CONTRIBUTING.md, PRIVACY.md, COPYING.md, CHANGELOG.md, and the base User's Guide). English is in fact an enforced project-wide convention: as stated in CONTRIBUTING.md ("English everywhere"), all source code, KDoc, test and build comments are written in English, and the tools/release-check.sh release gate rejects non-English prose in the source tree. Bug reports and code comments in English are welcome and handled by the maintainer.



    The project MUST be maintained. [maintained]
    As a minimum, the project should attempt to respond to significant problem and vulnerability reports. A project that is actively pursuing a badge is probably maintained. All projects and people have limited resources, and typical projects must reject some proposed changes, so limited resources and proposal rejections do not by themselves indicate an unmaintained project.

    When a project knows that it will no longer be maintained, it should set this criterion to "Unmet" and use the appropriate mechanism(s) to indicate to others that it is not being maintained. For example, use “DEPRECATED” as the first heading of its README, add “DEPRECATED” near the beginning of its home page, add “DEPRECATED” to the beginning of its code repository project description, add a no-maintenance-intended badge in its README and/or home page, mark it as deprecated in any package repositories (e.g., npm deprecate), and/or use the code repository's marking system to archive it (e.g., GitHub's "archive" setting, GitLab’s "archived" marking, Gerrit's "readonly" status, or SourceForge’s "abandoned" project status). Additional discussion can be found here.

    The project is actively maintained. It has a current release and a detailed, continuously updated CHANGELOG.md documenting a steady release cadence, with ongoing work on localization, build tooling, and QA hardening. The maintainer responds to issues and pull requests on Codeberg. See https://codeberg.org/godisch/potillus/src/branch/main/CHANGELOG.md


 Change Control 9/9

  • Public version-controlled source repository


    The project MUST have a version-controlled source repository that is publicly readable and has a URL. [repo_public]
    The URL MAY be the same as the project URL. The project MAY use private (non-public) branches in specific cases while the change is not publicly released (e.g., for fixing a vulnerability before it is revealed to the public).

    The project uses a publicly readable, version-controlled Git repository with a stable URL: https://codeberg.org/godisch/potillus — readable without an account and cloneable over HTTPS.



    The project's source repository MUST track what changes were made, who made the changes, and when the changes were made. [repo_track]

    The project's source repository uses Git, which inherently records, for every commit, what changed (the diff/tree), who made the change (author and committer identity), and when (author and commit timestamps). The full history is publicly browsable on Codeberg (commit list, diffs, and blame view) at https://codeberg.org/godisch/potillus/commits/branch/main



    To enable collaborative review, the project's source repository MUST include interim versions for review between releases; it MUST NOT include only final releases. [repo_interim]
    Projects MAY choose to omit specific interim versions from their public source repositories (e.g., ones that fix specific non-public security vulnerabilities, may never be publicly released, or include material that cannot be legally posted and are not in the final release).

    The repository contains ongoing interim development commits on the main branch between releases, not only final release snapshots, so work in progress is publicly available for collaborative review. The full commit history is browsable at https://codeberg.org/godisch/potillus/commits/branch/main



    It is SUGGESTED that common distributed version control software be used (e.g., git) for the project's source repository. [repo_distributed]
    Git is not specifically required and projects can use centralized version control software (such as subversion) with justification.

    The project uses Git, the most widely used distributed version control system, hosted on Codeberg (Forgejo). Repository: https://codeberg.org/godisch/potillus


  • Unique version numbering


    The project results MUST have a unique version identifier for each release intended to be used by users. [version_unique]
    This MAY be met in a variety of ways including a commit IDs (such as git commit id or mercurial changeset id) or a version number (including version numbers that use semantic versioning or date-based schemes like YYYYMMDD).

    Every user-facing release has a unique version identifier. The app carries a three-part versionName (MAJOR.MINOR.PATCH) and a strictly increasing integer versionCode, both defined in android/app/build.gradle.kts. CONTRIBUTING.md requires that the versionName, the top CHANGELOG.md entry, the README title, and the proguard-rules.pro header all carry the same version string and that versionCode increases by at least 1 each release; the tools/release-check.sh release gate enforces this consistency automatically. See https://codeberg.org/godisch/potillus/src/branch/main/CONTRIBUTING.md#7-versioning--release-checklist The iOS app shares the same single human-readable version: MARKETING_VERSION is derived from the top CHANGELOG.md entry (the same source of truth as Android's versionName), so a release carries one identical version string on both platforms.



    It is SUGGESTED that the Semantic Versioning (SemVer) or Calendar Versioning (CalVer) version numbering format be used for releases. It is SUGGESTED that those who use CalVer include a micro level value. [version_semver]
    Projects should generally prefer whatever format is expected by their users, e.g., because it is the normal format used by their ecosystem. Many ecosystems prefer SemVer, and SemVer is generally preferred for application programmer interfaces (APIs) and software development kits (SDKs). CalVer tends to be used by projects that are large, have an unusually large number of independently-developed dependencies, have a constantly-changing scope, or are time-sensitive. It is SUGGESTED that those who use CalVer include a micro level value, because including a micro level supports simultaneously-maintained branches whenever that becomes necessary. Other version numbering formats may be used as version numbers, including git commit IDs or mercurial changeset IDs, as long as they uniquely identify versions. However, some alternatives (such as git commit IDs) can cause problems as release identifiers, because users may not be able to easily determine if they are up-to-date. The version ID format may be unimportant for identifying software releases if all recipients only run the latest version (e.g., it is the code for a single website or internet service that is constantly updated via continuous delivery).


    It is SUGGESTED that projects identify each release within their version control system. For example, it is SUGGESTED that those using git identify each release using git tags. [version_tags]

    Each release is identified within the version control system by a git tag on Codeberg. Every published version has a corresponding tag of the form v<versionName>, so any release can be located and checked out directly from the repository history. Tags are browsable at https://codeberg.org/godisch/potillus/tags


  • Release notes


    The project MUST provide, in each release, release notes that are a human-readable summary of major changes in that release to help users determine if they should upgrade and what the upgrade impact will be. The release notes MUST NOT be the raw output of a version control log (e.g., the "git log" command results are not release notes). Projects whose results are not intended for reuse in multiple locations (such as the software for a single website or service) AND employ continuous delivery MAY select "N/A". (URL required) [release_notes]
    The release notes MAY be implemented in a variety of ways. Many projects provide them in a file named "NEWS", "CHANGELOG", or "ChangeLog", optionally with extensions such as ".txt", ".md", or ".html". Historically the term "change log" meant a log of every change, but to meet these criteria what is needed is a human-readable summary. The release notes MAY instead be provided by version control system mechanisms such as the GitHub Releases workflow.

    Each release is accompanied by human-readable release notes in CHANGELOG.md: a curated summary (not raw version-control log output), with a concise subject line plus prose describing the major changes, typically separating user-facing changes from internal ones so users can judge the upgrade impact. Localized store release notes are additionally maintained per versionCode under fastlane/metadata/android/<locale>/changelogs/. URL: https://codeberg.org/godisch/potillus/src/branch/main/CHANGELOG.md



    The release notes MUST identify every publicly known run-time vulnerability fixed in this release that already had a CVE assignment or similar when the release was created. This criterion may be marked as not applicable (N/A) if users typically cannot practically update the software themselves (e.g., as is often true for kernel updates). This criterion applies only to the project results, not to its dependencies. If there are no release notes or there have been no publicly known vulnerabilities, choose N/A. [release_notes_vulns]
    This criterion helps users determine if a given update will fix a vulnerability that is publicly known, to help users make an informed decision about updating. If users typically cannot practically update the software themselves on their computers, but must instead depend on one or more intermediaries to perform the update (as is often the case for a kernel and low-level software that is intertwined with a kernel), the project may choose "not applicable" (N/A) instead, since this additional information will not be helpful to those users. Similarly, a project may choose N/A if all recipients only run the latest version (e.g., it is the code for a single website or internet service that is constantly updated via continuous delivery). This criterion only applies to the project results, not its dependencies. Listing the vulnerabilities of all transitive dependencies of a project becomes unwieldy as dependencies increase and vary, and is unnecessary since tools that examine and track dependencies can do this in a more scalable way.

    Not applicable: to date there have been no publicly known run-time vulnerabilities in the project's own results (as opposed to its dependencies) that had a CVE assignment or similar at release time and were fixed in a release. As the criterion permits, N/A is selected because there have been no such publicly known vulnerabilities. Should this ever change, the fixed CVE(s) will be named in the corresponding CHANGELOG.md entry.


 Reporting 8/8

  • Bug-reporting process


    The project MUST provide a process for users to submit bug reports (e.g., using an issue tracker or a mailing list). (URL required) [report_process]

    Users submit bug reports through the project's Codeberg issue tracker, with android@godisch.de offered as an alternative. This process is documented in the README's "Feedback & Contributing" section. URL: https://codeberg.org/godisch/potillus/issues (documented at https://codeberg.org/godisch/potillus/src/branch/main/README.md#feedback--contributing)



    The project SHOULD use an issue tracker for tracking individual issues. [report_tracker]

    The project uses the Codeberg issue tracker to track individual issues. The tracker is enabled and public, and users are directed to it: the README ("Feedback & Contributing") and CONTRIBUTING.md §2 point bug reports and enhancement suggestions there, while SECURITY.md routes security-sensitive reports to a private channel instead. Issue tracker: https://codeberg.org/godisch/potillus/issues



    The project MUST acknowledge a majority of bug reports submitted in the last 2-12 months (inclusive); the response need not include a fix. [report_responses]

    No bug reports have been submitted in the last 2–12 months, so there are no unacknowledged reports; the requirement to acknowledge a majority of submitted bug reports is therefore satisfied. The Codeberg issue tracker is open and monitored for incoming reports: https://codeberg.org/godisch/potillus/issues



    The project SHOULD respond to a majority (>50%) of enhancement requests in the last 2-12 months (inclusive). [enhancement_responses]
    The response MAY be 'no' or a discussion about its merits. The goal is simply that there be some response to some requests, which indicates that the project is still alive. For purposes of this criterion, projects need not count fake requests (e.g., from spammers or automated systems). If a project is no longer making enhancements, please select "unmet" and include the URL that makes this situation clear to users. If a project tends to be overwhelmed by the number of enhancement requests, please select "unmet" and explain.

    No enhancement requests have been submitted in the last 2–12 months, so there are none left unanswered; the requirement to respond to a majority (>50%) of enhancement requests is satisfied. Enhancement requests are accepted via the Codeberg issue tracker: https://codeberg.org/godisch/potillus/issues



    The project MUST have a publicly available archive for reports and responses for later searching. (URL required) [report_archive]

    Reports and responses are publicly archived and searchable in the Codeberg issue tracker: all issues and pull requests — open and closed — remain publicly visible, are full-text searchable, and are addressable by stable URLs for later reference. URL: https://codeberg.org/godisch/potillus/issues?q=&type=all&state=all


  • Vulnerability report process


    The project MUST publish the process for reporting vulnerabilities on the project site. (URL required) [vulnerability_report_process]
    Projects hosted on GitHub SHOULD consider enabling privately reporting a security vulnerability. Projects on GitLab SHOULD consider using its ability for privately reporting a vulnerability. Projects MAY identify a mailing address on https://PROJECTSITE/security, often in the form security@example.org. This vulnerability reporting process MAY be the same as its bug reporting process. Vulnerability reports MAY always be public, but many projects have a private vulnerability reporting mechanism.

    The process for reporting vulnerabilities is published in SECURITY.md at the repository root (which Codeberg/Forgejo surfaces as the project's security policy) and is linked from the README's "Security" section. Reporters are asked to disclose privately via PGP-encrypted e-mail to android@godisch.de rather than opening a public issue. URL: https://codeberg.org/godisch/potillus/src/branch/main/SECURITY.md



    If private vulnerability reports are supported, the project MUST include how to send the information in a way that is kept private. (URL required) [vulnerability_report_private]
    Examples include a private defect report submitted on the web using HTTPS (TLS) or an email encrypted using OpenPGP. If vulnerability reports are always public (so there are never private vulnerability reports), choose "not applicable" (N/A).

    Private vulnerability reporting is the required path and SECURITY.md documents exactly how to send the information privately: a PGP-encrypted e-mail to android@godisch.de, using the maintainer's published key (fingerprint 1842 323B 4FCF 9B90 995F A17F A350 B991 F05A 4857), retrievable from the official Debian keyserver (hkps://keyring.debian.org:443). If a reporter cannot use PGP, the maintainer arranges a secure channel before any sensitive details are shared. URL: https://codeberg.org/godisch/potillus/src/branch/main/SECURITY.md



    The project's initial response time for any vulnerability report received in the last 6 months MUST be less than or equal to 14 days. [vulnerability_report_response]
    If there have been no vulnerabilities reported in the last 6 months, choose "not applicable" (N/A).

    Not applicable: no vulnerability reports have been received in the last 6 months, so there is no initial response time to measure. SECURITY.md nevertheless commits to acknowledging any future vulnerability report within 14 days, so the requirement is covered in advance; this item will be marked Met once a report has been received and handled within that window.


 Quality 13/13

  • Working build system


    If the software produced by the project requires building for use, the project MUST provide a working build system that can automatically rebuild the software from source code. [build]
    A build system determines what actions need to occur to rebuild the software (and in what order), and then performs those steps. For example, it can invoke a compiler to compile the source code. If an executable is created from source code, it must be possible to modify the project's source code and then generate an updated executable with those modifications. If the software produced by the project depends on external libraries, the build system does not need to build those external libraries. If there is no need to build anything to use the software after its source code is modified, select "not applicable" (N/A).

    The application is built from source with Gradle. The repository contains the full build definition (android/build.gradle.kts, android/app/build.gradle.kts, android/settings.gradle.kts), a checked-in Gradle wrapper (gradlew / gradlew.bat), and an orchestrating Makefile, so the software can be automatically rebuilt from source (e.g. ./gradlew assembleRelease). As independent evidence, F-Droid reproducibly builds the app from this same source (see fdroid/de.godisch.potillus.yml). Repository: https://codeberg.org/godisch/potillus On iOS, make ios regenerates the Xcode project with XcodeGen and builds via the Swift toolchain, so a single documented command produces the app.



    It is SUGGESTED that common tools be used for building the software. [build_common_tools]
    For example, Maven, Ant, cmake, the autotools, make, rake (Ruby), or devtools (R).

    The project builds with the standard, widely used Android toolchain: Gradle (with the Kotlin DSL) and the Android Gradle Plugin, the Kotlin compiler, and the checked-in Gradle wrapper, orchestrated by a Makefile. These are the conventional build tools for Android applications. The iOS app uses the standard Apple toolchain: the Swift compiler and Swift Package Manager for the PotillusKit package, an Xcode project generated declaratively by XcodeGen from ios/project.yml, all driven by the same Makefile. These are conventional iOS build tools.



    The project SHOULD be buildable using only FLOSS tools. [build_floss_tools]

    The build toolchain itself is FLOSS: Gradle, the Gradle wrapper, the Android Gradle Plugin, and the Kotlin compiler are all Apache-2.0 licensed. F-Droid builds and distributes the app entirely within its free-software build pipeline (see fdroid/de.godisch.potillus.yml), demonstrating the project is buildable with FLOSS tooling. Note: some Android SDK components (build-tools, the platform android.jar) are under the non-OSI Android SDK License — a well-known caveat common to all Android apps — but the project itself introduces no proprietary build tools. The iOS build likewise relies on FLOSS or freely-available tooling: the open-source Swift toolchain and Swift Package Manager, XcodeGen (MIT), and SwiftLint (MIT); Xcode itself is the platform's free IDE.


  • Automated test suite


    The project MUST use at least one automated test suite that is publicly released as FLOSS (this test suite may be maintained as a separate FLOSS project). The project MUST clearly show or document how to run the test suite(s) (e.g., via a continuous integration (CI) script or via documentation in files such as BUILD.md, README.md, or CONTRIBUTING.md). [test]
    The project MAY use multiple automated test suites (e.g., one that runs quickly, vs. another that is more thorough but requires special equipment). There are many test frameworks and test support systems available, including Selenium (web browser automation), Junit (JVM, Java), RUnit (R), testthat (R).

    The project ships a substantial automated test suite, released as FLOSS under GPL-3.0-or-later in the same repository: JVM unit tests in android/app/src/test/ (domain, data, l10n, util, and ViewModel layers, plus LocaleSyncTest) and instrumented tests in android/app/src/androidTest/ (Room migration validation, Compose UI components, on-device locale formatting), using FLOSS test frameworks (JUnit, AndroidX/Compose testing). How to run the tests is documented in CONTRIBUTING.md §5 "Testing strategy" (./gradlew :app:test for unit tests, ./gradlew :app:connectedAndroidTest for instrumented tests) and §7. See https://codeberg.org/godisch/potillus/src/branch/main/CONTRIBUTING.md#5-testing-strategy The iOS side mirrors this: a broad PotillusKit unit-test suite plus app-target tests, sharing golden vectors with Android so the two implementations are held to the same expected results.



    A test suite SHOULD be invocable in a standard way for that language. [test_invocation]
    For example, "make check", "mvn test", or "rake test" (Ruby).

    The test suite is invoked in the standard way for a Gradle/Android project: ./gradlew test runs the JVM unit tests and ./gradlew connectedCheck runs the instrumented tests on a device or emulator. This conventional invocation is documented in CONTRIBUTING.md (Section 5, "Testing strategy", and the change-submission checklist in Section 2). URL: https://codeberg.org/godisch/potillus/src/branch/main/CONTRIBUTING.md The iOS tests are invoked the standard way too: swift test runs the PotillusKit unit tests, and the app-target tests run under xcodebuild. Both are wired into the Makefile's iOS targets.



    It is SUGGESTED that the test suite cover most (or ideally all) the code branches, input fields, and functionality. [test_most]

    The project has an automated test suite (JVM unit tests plus instrumented tests) covering the major functionality; statement coverage of the unit-testable code is ~97% (Kover), enforced via koverVerify.



    It is SUGGESTED that the project implement continuous integration (where new or changed code is frequently integrated into a central code repository and automated tests are run on the result). [test_continuous_integration]

    Not currently implemented. The project is maintained by a single developer who builds and runs the full test suite and release gate (tools/release-check.sh) locally before each release, but there is no central CI service running automated tests on every change. This criterion is SUGGESTED at passing and a MUST at gold; the planned remediation is a Woodpecker pipeline (.woodpecker.yml) on Codeberg that runs the JVM unit tests (and lint/ktlint) on each push and reports success or failure — the same work as the silver automated_integration_testing item. Tracked in docs/ROADMAP.md.


  • New functionality testing


    The project MUST have a general policy (formal or not) that as major new functionality is added to the software produced by the project, tests of that functionality should be added to an automated test suite. [test_policy]
    As long as a policy is in place, even by word of mouth, that says developers should add tests to the automated test suite for major new functionality, select "Met."

    The project has a written policy that new functionality ships with tests. CONTRIBUTING.md §5 ("Testing strategy") states that the domain layer is the coverage floor and that new domain logic ships with its own tests, and §2 (step 3) makes passing the tests and following the §5 testing conventions a precondition for accepting any change. See https://codeberg.org/godisch/potillus/src/branch/main/CONTRIBUTING.md#5-testing-strategy



    The project MUST have evidence that the test_policy for adding tests has been adhered to in the most recent major changes to the software produced by the project. [tests_are_added]
    Major functionality would typically be mentioned in the release notes. Perfection is not required, merely evidence that tests are typically being added in practice to the automated test suite when new major functionality is added to the software produced by the project.

    The add-tests policy is demonstrably followed. The test tree mirrors the source almost one-to-one: each non-trivial domain and utility class has a dedicated test (AlcoholCalculator, DayResolver, ChartBucketing, Trend, LocaleDetector, BackupManager, CsvExporter, …), every ViewModel has its own test class, schema changes are guarded by MigrationTest, and new locales/strings are guarded by LocaleSyncTest, which fails the build if a translation is incomplete. Recent releases include this test and QA work (see CHANGELOG.md). The commit history shows feature changes landing together with their tests. Tests: https://codeberg.org/godisch/potillus/src/branch/main/android/app/src/test



    It is SUGGESTED that this policy on adding tests (see test_policy) be documented in the instructions for change proposals. [tests_documented_added]
    However, even an informal rule is acceptable as long as the tests are being added in practice.

    The project's documented instructions for change proposals include the test-addition policy. CONTRIBUTING.md §2 ("Submitting changes"), step 3, states that per the mandatory test policy in §5, major new functionality MUST include automated tests covering it in the same change, and that ./gradlew test must pass and the release gate must stay green. The full policy is defined in §5. URL: https://codeberg.org/godisch/potillus/src/branch/main/CONTRIBUTING.md#2-submitting-changes


  • Warning flags


    The project MUST enable one or more compiler warning flags, a "safe" language mode, or use a separate "linter" tool to look for code quality errors or common simple mistakes, if there is at least one FLOSS tool that can implement this criterion in the selected language. [warnings]
    Examples of compiler warning flags include gcc/clang "-Wall". Examples of a "safe" language mode include JavaScript "use strict" and perl5's "use warnings". A separate "linter" tool is simply a tool that examines the source code to look for code quality errors or common simple mistakes. These are typically enabled within the source code or build instructions.

    The project enables both a linter and strict compiler warnings, using FLOSS tools. Android Lint is run as a build gate (./gradlew lintDebug) configured in android/app/build.gradle.kts with abortOnError = true and warningsAsErrors = true, so lint warnings fail the build. In addition, the Kotlin compiler is configured with allWarningsAsErrors.set(true), promoting every compiler warning to a build-breaking error. The project deliberately uses no lint baseline (no silent suppression); the few exceptions are explicit and documented in the build file. See https://codeberg.org/godisch/potillus/src/branch/main/android/app/build.gradle.kts



    The project MUST address warnings. [warnings_fixed]
    These are the warnings identified by the implementation of the warnings criterion. The project should fix warnings or mark them in the source code as false positives. Ideally there would be no warnings, but a project MAY accept some warnings (typically less than 1 warning per 100 lines or less than 10 warnings).

    Warnings are addressed by construction: because Android Lint is configured with warningsAsErrors = true and the Kotlin compiler with allWarningsAsErrors = true, any unaddressed warning breaks the build, so a release cannot be produced with outstanding warnings and the source tree stays warning-free. The few deliberate exceptions are explicit and reviewable in android/app/build.gradle.kts rather than hidden in a suppression baseline. See https://codeberg.org/godisch/potillus/src/branch/main/android/app/build.gradle.kts



    It is SUGGESTED that projects be maximally strict with warnings in the software produced by the project, where practical. [warnings_strict]
    Some warnings cannot be effectively enabled on some projects. What is needed is evidence that the project is striving to enable warning flags where it can, so that errors are detected early.

    The project is maximally strict with warnings. The Kotlin compiler runs with allWarningsAsErrors = true, so every compiler warning fails the build, and Android Lint runs with warningsAsErrors = true and abortOnError = true, promoting every lint warning to a build-breaking error. Rather than suppressing warnings, the project removes their causes and re-enables checks once underlying tooling bugs are fixed (e.g. the PluralsCandidate and WrongStartDestinationType lint checks were restored after workarounds were no longer needed). ktlint was additionally added as a style checker. URL: https://codeberg.org/godisch/potillus/src/branch/main/android/app/build.gradle.kts


 Security 16/16

  • Secure development knowledge


    The project MUST have at least one primary developer who knows how to design secure software. (See ‘details’ for the exact requirements.) [know_secure_design]
    This requires understanding the following design principles, including the 8 principles from Saltzer and Schroeder:
    • economy of mechanism (keep the design as simple and small as practical, e.g., by adopting sweeping simplifications)
    • fail-safe defaults (access decisions should deny by default, and projects' installation should be secure by default)
    • complete mediation (every access that might be limited must be checked for authority and be non-bypassable)
    • open design (security mechanisms should not depend on attacker ignorance of its design, but instead on more easily protected and changed information like keys and passwords)
    • separation of privilege (ideally, access to important objects should depend on more than one condition, so that defeating one protection system won't enable complete access. E.G., multi-factor authentication, such as requiring both a password and a hardware token, is stronger than single-factor authentication)
    • least privilege (processes should operate with the least privilege necessary)
    • least common mechanism (the design should minimize the mechanisms common to more than one user and depended on by all users, e.g., directories for temporary files)
    • psychological acceptability (the human interface must be designed for ease of use - designing for "least astonishment" can help)
    • limited attack surface (the attack surface - the set of the different points where an attacker can try to enter or extract data - should be limited)
    • input validation with allowlists (inputs should typically be checked to determine if they are valid before they are accepted; this validation should use allowlists (which only accept known-good values), not denylists (which attempt to list known-bad values)).
    A "primary developer" in a project is anyone who is familiar with the project's code base, is comfortable making changes to it, and is acknowledged as such by most other participants in the project. A primary developer would typically make a number of contributions over the past year (via code, documentation, or answering questions). Developers would typically be considered primary developers if they initiated the project (and have not left the project more than three years ago), have the option of receiving information on a private vulnerability reporting channel (if there is one), can accept commits on behalf of the project, or perform final releases of the project software. If there is only one developer, that individual is the primary developer. Many books and courses are available to help you understand how to develop more secure software and discuss design. For example, the Secure Software Development Fundamentals course is a free set of three courses that explain how to develop more secure software (it's free if you audit it; for an extra fee you can earn a certificate to prove you learned the material).

    The project's primary developer (a Debian Developer) knows how to design secure software, and the application embodies established secure-design principles: least privilege and minimized attack surface (no network permission at all, no camera/microphone/location, and API 30 chosen so that even storage runtime permissions are unnecessary); fail-safe/secure defaults and data minimization (offline-only, no analytics or crash reporting, data confined to the app sandbox and encrypted at rest); reliance on vetted cryptography rather than home-grown implementations (hardware-backed Android Keystore, encrypted DataStore); defensive input validation and fail-secure behaviour (the JSON backup importer rejects too-new files and reads optional fields defensively, enums deserialize via runCatching{…}.getOrDefault(…)); and open design (fully GPL-3.0-or-later open source and auditable).



    At least one of the project's primary developers MUST know of common kinds of errors that lead to vulnerabilities in this kind of software, as well as at least one method to counter or mitigate each of them. [know_common_errors]
    Examples (depending on the type of software) include SQL injection, OS injection, classic buffer overflow, cross-site scripting, missing authentication, and missing authorization. See the CWE/SANS top 25 or OWASP Top 10 for commonly used lists. Many books and courses are available to help you understand how to develop more secure software and discuss common implementation errors that lead to vulnerabilities. For example, the Secure Software Development Fundamentals course is a free set of three courses that explain how to develop more secure software (it's free if you audit it; for an extra fee you can earn a certificate to prove you learned the material).

    A primary developer knows the common error classes that lead to vulnerabilities in an Android application (cf. the OWASP Mobile Top 10) and at least one mitigation for each, as reflected in the code: injection is avoided by using Room's parameterized queries rather than string concatenation; insecure data storage is mitigated by the app sandbox, encryption at rest, and keeping sensitive keys in the hardware-backed Android Keystore; unsafe deserialization / missing input validation is mitigated by defensive backup-import parsing (optional-field fallbacks, rejection of too-new files via VersionTooHigh, and runCatching{…}.getOrDefault(…) for enums); excessive attack surface is mitigated by a minimal permission profile with no network permission; insecure IPC is avoided by not exporting unnecessary components; and weak/home-grown cryptography is avoided by relying on the platform's vetted cryptographic facilities.


  • Use basic good cryptographic practices

    Note that some software does not need to use cryptographic mechanisms. If your project produces software that (1) includes, activates, or enables encryption functionality, and (2) might be released from the United States (US) to outside the US or to a non-US-citizen, you may be legally required to take a few extra steps. Typically this just involves sending an email. For more information, see the encryption section of Understanding Open Source Technology & US Export Controls.

    The software produced by the project MUST use, by default, only cryptographic protocols and algorithms that are publicly published and reviewed by experts (if cryptographic protocols and algorithms are used). [crypto_published]
    These cryptographic criteria do not always apply because some software has no need to directly use cryptographic capabilities.

    The only cryptography the software uses is AES-256 in GCM mode (AES/GCM/NoPadding) to encrypt the preferences at rest, with the key held in the Android Keystore. These are publicly published, expert-reviewed standards (NIST FIPS 197 for AES, NIST SP 800-38D for GCM); no proprietary or home-grown algorithms are used. See android/app/src/main/kotlin/de/godisch/potillus/data/security/KeystoreSecretStore.kt The iOS implementation likewise uses only published, standard algorithms (AES-256-GCM via Apple's CryptoKit); no proprietary cryptography is introduced.



    If the software produced by the project is an application or library, and its primary purpose is not to implement cryptography, then it SHOULD only call on software specifically designed to implement cryptographic functions; it SHOULD NOT re-implement its own. [crypto_call]

    The application's primary purpose is alcohol tracking, not cryptography. It calls only platform-provided cryptographic facilities — javax.crypto.Cipher and KeyGenerator, with keys managed by the Android Keystore via KeyGenParameterSpec/KeyProperties — and does not re-implement any cryptographic primitives. Key generation, IV generation, encryption/decryption, and the GCM authentication tag are all handled by the platform provider. See android/app/src/main/kotlin/de/godisch/potillus/data/security/KeystoreSecretStore.kt On iOS the same holds: the app calls only platform cryptography — Apple's CryptoKit (AES.GCM) for sealing the preferences and the Security-framework Keychain for the key — and re-implements no primitives. See ios/PotillusKit/Sources/PotillusKit/Data/PreferencesStore.swift and SecretKeyProviding.swift.



    All functionality in the software produced by the project that depends on cryptography MUST be implementable using FLOSS. [crypto_floss]

    The only crypto-dependent functionality — encrypting the preferences at rest with AES-256-GCM through the standard JCA interface (javax.crypto.Cipher / KeyGenerator) — relies on open standards for which FLOSS implementations exist (e.g. BouncyCastle, Conscrypt). Nothing depends on a proprietary, non-replaceable cryptographic component, so all cryptography-dependent functionality is implementable using FLOSS.



    The security mechanisms within the software produced by the project MUST use default keylengths that at least meet the NIST minimum requirements through the year 2030 (as stated in 2012). It MUST be possible to configure the software so that smaller keylengths are completely disabled. [crypto_keylength]
    These minimum bitlengths are: symmetric key 112, factoring modulus 2048, discrete logarithm key 224, discrete logarithmic group 2048, elliptic curve 224, and hash 224 (password hashing is not covered by this bitlength, more information on password hashing can be found in the crypto_password_storage criterion). See https://www.keylength.com for a comparison of keylength recommendations from various organizations. The software MAY allow smaller keylengths in some configurations (ideally it would not, since this allows downgrade attacks, but shorter keylengths are sometimes necessary for interoperability).

    The security mechanism uses AES with a 256-bit key (setKeySize(256) in the KeyGenParameterSpec), which far exceeds the NIST minimum keylength requirements through 2030. Smaller keylengths are not merely non-default but impossible: the key is generated at a fixed 256-bit size inside the Android Keystore and there is no configuration path to any smaller length, so shorter keylengths are completely disabled by construction. See android/app/src/main/kotlin/de/godisch/potillus/data/security/KeystoreSecretStore.kt The iOS side matches: the key is a CryptoKit SymmetricKey fixed at 256 bits (SymmetricKey(size: .bits256)), with no configuration path to a smaller length.



    The default security mechanisms within the software produced by the project MUST NOT depend on broken cryptographic algorithms (e.g., MD4, MD5, single DES, RC4, Dual_EC_DRBG), or use cipher modes that are inappropriate to the context, unless they are necessary to implement an interoperable protocol (where the protocol implemented is the most recent version of that standard broadly supported by the network ecosystem, that ecosystem requires the use of such an algorithm or mode, and that ecosystem does not offer any more secure alternative). The documentation MUST describe any relevant security risks and any known mitigations if these broken algorithms or modes are necessary for an interoperable protocol. [crypto_working]
    ECB mode is almost never appropriate because it reveals identical blocks within the ciphertext as demonstrated by the ECB penguin, and CTR mode is often inappropriate because it does not perform authentication and causes duplicates if the input state is repeated. In many cases it's best to choose a block cipher algorithm mode designed to combine secrecy and authentication, e.g., Galois/Counter Mode (GCM) and EAX. Projects MAY allow users to enable broken mechanisms (e.g., during configuration) where necessary for compatibility, but then users know they're doing it.

    The default (and only) security mechanism uses AES-256-GCM; it depends on none of the broken algorithms named by the criterion (no MD4/MD5, single DES, RC4, or Dual_EC_DRBG). GCM is an AEAD cipher mode that is appropriate for the context (authenticated encryption of data at rest), used correctly with a fresh random 96-bit IV per encryption and a 128-bit authentication tag — not ECB and not a static IV. See android/app/src/main/kotlin/de/godisch/potillus/data/security/KeystoreSecretStore.kt On iOS the CryptoKit AES-GCM seal/open round-trip is covered by the PotillusKit test suite, so the encryption path is exercised, not just assumed.



    The default security mechanisms within the software produced by the project SHOULD NOT depend on cryptographic algorithms or modes with known serious weaknesses (e.g., the SHA-1 cryptographic hash algorithm or the CBC mode in SSH). [crypto_weaknesses]
    Concerns about CBC mode in SSH are discussed in CERT: SSH CBC vulnerability.

    The software's default security mechanisms use only strong, modern cryptography and none of the known-weak algorithms or modes. The encrypted preferences store uses AES-256 in GCM (authenticated encryption) — not ECB, CBC, DES/3DES, or RC4 — with the key held in the hardware-backed Android Keystore, a 96-bit random IV per encryption drawn from a cryptographically secure RNG, and a 128-bit authentication tag. No weak hash functions (e.g. MD5 or SHA-1) are used in the security mechanisms. URL: https://codeberg.org/godisch/potillus/src/branch/main/android/app/src/main/kotlin/de/godisch/potillus/data/security/KeystoreSecretStore.kt The iOS path uses the same modern AEAD construction (AES-256-GCM via CryptoKit), avoiding the broken or weak algorithms the criterion warns against.



    The security mechanisms within the software produced by the project SHOULD implement perfect forward secrecy for key agreement protocols so a session key derived from a set of long-term keys cannot be compromised if one of the long-term keys is compromised in the future. [crypto_pfs]

    Not applicable: the software performs no key agreement and has no network protocol or sessions. It only encrypts local data at rest using a symmetric AES-256-GCM key stored in the Android Keystore. Perfect forward secrecy concerns session keys derived via key-agreement protocols, which this application does not use, so the criterion does not apply.



    If the software produced by the project causes the storing of passwords for authentication of external users, the passwords MUST be stored as iterated hashes with a per-user salt by using a key stretching (iterated) algorithm (e.g., Argon2id, Bcrypt, Scrypt, or PBKDF2). See also OWASP Password Storage Cheat Sheet. [crypto_password_storage]
    This criterion applies only when the software is enforcing authentication of users using passwords for external users (aka inbound authentication), such as server-side web applications. It does not apply in cases where the software stores passwords for authenticating into other systems (aka outbound authentication, e.g., the software implements a client for some other system), since at least parts of that software must have often access to the unhashed password.

    Not applicable: the application does not authenticate external users and stores no passwords. It is a local, single-user app with no accounts, login, or server component. The optional biometric fingerprint lock is a device-local access gate via the Android BiometricPrompt API and stores or hashes no password, so there is no password storage to which this criterion could apply.



    The security mechanisms within the software produced by the project MUST generate all cryptographic keys and nonces using a cryptographically secure random number generator, and MUST NOT do so using generators that are cryptographically insecure. [crypto_random]
    A cryptographically secure random number generator may be a hardware random number generator, or it may be a cryptographically secure pseudo-random number generator (CSPRNG) using an algorithm such as Hash_DRBG, HMAC_DRBG, CTR_DRBG, Yarrow, or Fortuna. Examples of calls to secure random number generators include Java's java.security.SecureRandom and JavaScript's window.crypto.getRandomValues. Examples of calls to insecure random number generators include Java's java.util.Random and JavaScript's Math.random.

    All cryptographic keys and nonces are generated by the platform's cryptographically secure provider, not by an insecure generator (e.g. java.util.Random). The AES-256 key is generated inside the Android Keystore via KeyGenerator/KeyGenParameterSpec, and the 96-bit GCM IV is produced fresh per encryption by the crypto provider (cipher.iv), enforced by setRandomizedEncryptionRequired(true); no caller-chosen or static IV is used. See android/app/src/main/kotlin/de/godisch/potillus/data/security/KeystoreSecretStore.kt On iOS the AES-256 key is created by CryptoKit's SymmetricKey(size: .bits256) and each GCM nonce is generated fresh by CryptoKit per seal (AES.GCM.seal), never caller-chosen or static — the same secure-provider guarantee.


  • Secured delivery against man-in-the-middle (MITM) attacks


    The project MUST use a delivery mechanism that counters MITM attacks. Using https or ssh+scp is acceptable. [delivery_mitm]
    An even stronger mechanism is releasing the software with digitally signed packages, since that mitigates attacks on the distribution system, but this only works if the users can be confident that the public keys for signatures are correct and if the users will actually check the signature.

    The project uses MITM-resistant delivery for both source and application. The source repository is cloned and browsed over HTTPS (or SSH) from Codeberg. The app is distributed via F-Droid over HTTPS, and F-Droid additionally signs all packages and verifies the signature on install and update, protecting integrity even against a compromised transport path. Repository: https://codeberg.org/godisch/potillus — distribution: https://f-droid.org/packages/de.godisch.potillus



    A cryptographic hash (e.g., a sha1sum) MUST NOT be retrieved over http and used without checking for a cryptographic signature. [delivery_unsigned]
    These hashes can be modified in transit.

    The project does not retrieve a cryptographic hash over HTTP and use it without a signature check. Distribution via F-Droid relies on cryptographically signed packages and a signed repository index, so integrity is verified through signatures rather than an unsigned hash fetched over HTTP; source is obtained from Codeberg over HTTPS. There is no point in the delivery process where an HTTP-retrieved hash is used without signature verification.


  • Publicly known vulnerabilities fixed


    There MUST be no unpatched vulnerabilities of medium or higher severity that have been publicly known for more than 60 days. [vulnerabilities_fixed_60_days]
    The vulnerability must be patched and released by the project itself (patches may be developed elsewhere). A vulnerability becomes publicly known (for this purpose) once it has a CVE with publicly released non-paywalled information (reported, for example, in the National Vulnerability Database) or when the project has been informed and the information has been released to the public (possibly by the project). A vulnerability is considered medium or higher severity if its Common Vulnerability Scoring System (CVSS) base qualitative score is medium or higher. In CVSS versions 2.0 through 3.1, this is equivalent to a CVSS score of 4.0 or higher. Projects may use the CVSS score as published in a widely-used vulnerability database (such as the National Vulnerability Database) using the most-recent version of CVSS reported in that database. Projects may instead calculate the severity themselves using the latest version of CVSS at the time of the vulnerability disclosure, if the calculation inputs are publicly revealed once the vulnerability is publicly known. Note: this means that users might be left vulnerable to all attackers worldwide for up to 60 days. This criterion is often much easier to meet than what Google recommends in Rebooting responsible disclosure, because Google recommends that the 60-day period start when the project is notified even if the report is not public. Also note that this badge criterion, like other criteria, applies to the individual project. Some projects are part of larger umbrella organizations or larger projects, possibly in multiple layers, and many projects feed their results to other organizations and projects as part of a potentially-complex supply chain. An individual project often cannot control the rest, but an individual project can work to release a vulnerability patch in a timely way. Therefore, we focus solely on the individual project's response time. Once a patch is available from the individual project, others can determine how to deal with the patch (e.g., they can update to the newer version or they can apply just the patch as a cherry-picked solution).

    There are no unpatched vulnerabilities of medium or higher severity that have been publicly known for more than 60 days. No CVEs have been filed against the application, and its network-free, minimal-permission architecture keeps the attack surface small; dependencies are kept current. The maintainer confirms no such known unpatched vulnerabilities exist.



    Projects SHOULD fix all critical vulnerabilities rapidly after they are reported. [vulnerabilities_critical_fixed]

    No critical vulnerabilities have been reported to date, so none remain unfixed. A process to handle them promptly is in place: SECURITY.md defines a private reporting channel with a 14-day acknowledgement commitment and coordinated fix/disclosure, and the project's regular release cadence demonstrates the ability to ship fixes quickly. See https://codeberg.org/godisch/potillus/src/branch/main/SECURITY.md


  • Other security issues


    The public repositories MUST NOT leak a valid private credential (e.g., a working password or private key) that is intended to limit public access. [no_leaked_credentials]
    A project MAY leak "sample" credentials for testing and unimportant databases, as long as they are not intended to limit public access.

    The public repository leaks no valid private credentials. It contains no keystore or private-key files (no .jks/.keystore/.pem/.p12, no real keystore.properties) and no hard-coded passwords or API keys. Release signing material and the Google Play service-account key are explicitly git-ignored (/android/keystore.properties, /fastlane/play-store-credentials.json) and marked "SECRET, never commit"; only a documented placeholder template (android/keystore.properties.example) is committed, and the Play key is referenced only by path/SUPPLY_JSON_KEY, never embedded.


 Analysis 8/8

  • Static code analysis


    At least one static code analysis tool (beyond compiler warnings and "safe" language modes) MUST be applied to any proposed major production release of the software before its release, if there is at least one FLOSS tool that implements this criterion in the selected language. [static_analysis]
    A static code analysis tool examines the software code (as source code, intermediate code, or executable) without executing it with specific inputs. For purposes of this criterion, compiler warnings and "safe" language modes do not count as static code analysis tools (these typically avoid deep analysis because speed is vital). Some static analysis tools focus on detecting generic defects, others focus on finding specific kinds of defects (such as vulnerabilities), and some do a combination. Examples of such static code analysis tools include cppcheck (C, C++), clang static analyzer (C, C++), SpotBugs (Java), FindBugs (Java) (including FindSecurityBugs), PMD (Java), Brakeman (Ruby on Rails), lintr (R), goodpractice (R), Coverity Quality Analyzer, SonarQube, Codacy, and HP Enterprise Fortify Static Code Analyzer. Larger lists of tools can be found in places such as the Wikipedia list of tools for static code analysis, OWASP information on static code analysis, NIST list of source code security analyzers, and Wheeler's list of static analysis tools. If there are no FLOSS static analysis tools available for the implementation language(s) used, you may select 'N/A'.

    Android Lint, a FLOSS static analysis tool that goes well beyond compiler warnings and safe-language modes (it analyzes code, resources, the manifest, API usage, correctness, performance, and security across hundreds of rules), is applied to every release as a build gate: android/app/build.gradle.kts configures lint { abortOnError = true; warningsAsErrors = true } and the release process runs ./gradlew lintDebug, so a release cannot be produced while Lint reports any issue. See https://codeberg.org/godisch/potillus/src/branch/main/android/app/build.gradle.kts The iOS counterpart is SwiftLint, pinned to a fixed version (0.65.0) and run in --strict mode as a release gate (check-swiftlint), so a warning fails the build; seven project-specific Python linters add header, localisation, and parity checks on top.



    It is SUGGESTED that at least one of the static analysis tools used for the static_analysis criterion include rules or approaches to look for common vulnerabilities in the analyzed language or environment. [static_analysis_common_vulnerabilities]
    Static analysis tools that are specifically designed to look for common vulnerabilities are more likely to find them. That said, using any static tools will typically help find some problems, so we are suggesting but not requiring this for the 'passing' level badge.

    The static analysis tool used for static_analysis — Android Lint — includes a dedicated set of security detectors that look for common Android-environment vulnerabilities (e.g. exported components and permission issues, cleartext traffic, hardcoded credentials, weak cryptography, unsafe WebView/TrustManager patterns, and SQL-injection/path-traversal hints). The build runs Lint with abortOnError = true and warningsAsErrors = true, so such findings are enforced as build-breaking errors rather than merely reported. This is complemented by osv-scanner dependency scanning (SECURITY.md, "Dependency monitoring"). URL: https://codeberg.org/godisch/potillus/src/branch/main/android/app/build.gradle.kts



    All medium and higher severity exploitable vulnerabilities discovered with static code analysis MUST be fixed in a timely way after they are confirmed. [static_analysis_fixed]
    A vulnerability is considered medium or higher severity if its Common Vulnerability Scoring System (CVSS) base qualitative score is medium or higher. In CVSS versions 2.0 through 3.1, this is equivalent to a CVSS score of 4.0 or higher. Projects may use the CVSS score as published in a widely-used vulnerability database (such as the National Vulnerability Database) using the most-recent version of CVSS reported in that database. Projects may instead calculate the severity themselves using the latest version of CVSS at the time of the vulnerability disclosure, if the calculation inputs are publicly revealed once the vulnerability is publicly known. Note that criterion vulnerabilities_fixed_60_days requires that all such vulnerabilities be fixed within 60 days of being made public.

    Findings from static analysis cannot reach a release: Android Lint runs as a release gate with abortOnError = true and warningsAsErrors = true, so any reported issue breaks the build and must be fixed (or made an explicit, reviewable exception) before a release can be produced. Timely remediation is thus enforced by construction, and no exploitable medium-or-higher findings are currently outstanding. See https://codeberg.org/godisch/potillus/src/branch/main/android/app/build.gradle.kts



    It is SUGGESTED that static source code analysis occur on every commit or at least daily. [static_analysis_often]

    Not currently met. Android Lint (the project's static analysis tool) runs locally on every build and as a mandatory gate before each release, but there is no central continuous-integration service running it automatically on every commit or at least daily, as this criterion suggests. This is a SUGGESTED criterion and does not block the passing badge. Planned remediation: add Codeberg Woodpecker CI with a .woodpecker.yml step that runs ./gradlew lintDebug on every push, which will satisfy this criterion together with test_continuous_integration.


  • Dynamic code analysis


    It is SUGGESTED that at least one dynamic analysis tool be applied to any proposed major production release of the software before its release. [dynamic_analysis]
    A dynamic analysis tool examines the software by executing it with specific inputs. For example, the project MAY use a fuzzing tool (e.g., American Fuzzy Lop) or a web application scanner (e.g., OWASP ZAP or w3af). In some cases the OSS-Fuzz project may be willing to apply fuzz testing to your project. For purposes of this criterion the dynamic analysis tool needs to vary the inputs in some way to look for various kinds of problems or be an automated test suite with at least 80% branch coverage. The Wikipedia page on dynamic analysis and the OWASP page on fuzzing identify some dynamic analysis tools. The analysis tool(s) MAY be focused on looking for security vulnerabilities, but this is not required.

    No dedicated dynamic analysis tool (fuzzer, sanitizer, or scanner) is applied before releases, and branch coverage is not yet measured, so the "automated test suite with ≥80% branch coverage counts as dynamic analysis" allowance cannot yet be claimed. The instrumented tests do exercise the app on a device/emulator, but without a measured ≥80% branch-coverage figure this does not yet meet the criterion. Remediation is tied to the Kover branch-coverage work in docs/ROADMAP.md; alternatively a dedicated dynamic tool could be added.



    It is SUGGESTED that if the software produced by the project includes software written using a memory-unsafe language (e.g., C or C++), then at least one dynamic tool (e.g., a fuzzer or web application scanner) be routinely used in combination with a mechanism to detect memory safety problems such as buffer overwrites. If the project does not produce software written in a memory-unsafe language, choose "not applicable" (N/A). [dynamic_analysis_unsafe]
    Examples of mechanisms to detect memory safety problems include Address Sanitizer (ASAN) (available in GCC and LLVM), Memory Sanitizer, and valgrind. Other potentially-used tools include thread sanitizer and undefined behavior sanitizer. Widespread assertions would also work.

    Not applicable. The software is written entirely in Kotlin running on the memory-safe JVM/ART runtime, with automatic memory management and no manual allocation, pointer arithmetic, or buffer handling. The project produces no memory-unsafe (C/C++/NDK) code, so there is no unsafe memory use for a dynamic analysis tool to detect.



    It is SUGGESTED that the project use a configuration for at least some dynamic analysis (such as testing or fuzzing) which enables many assertions. In many cases these assertions should not be enabled in production builds. [dynamic_analysis_enable_assertions]
    This criterion does not suggest enabling assertions during production; that is entirely up to the project and its users to decide. This criterion's focus is instead to improve fault detection during dynamic analysis before deployment. Enabling assertions in production use is completely different from enabling assertions during dynamic analysis (such as testing). In some cases enabling assertions in production use is extremely unwise (especially in high-integrity components). There are many arguments against enabling assertions in production, e.g., libraries should not crash callers, their presence may cause rejection by app stores, and/or activating an assertion in production may expose private data such as private keys. Beware that in many Linux distributions NDEBUG is not defined, so C/C++ assert() will by default be enabled for production in those environments. It may be important to use a different assertion mechanism or defining NDEBUG for production in those environments.

    Not met (SHOULD). The criterion targets fault detection during dynamic analysis (testing), not production. The produced code contains a small number of always-on Kotlin preconditions (require/check/error) that are checked whenever the code runs, including under the test suite, but not "many". Remediation (tracked in docs/ROADMAP.md): add invariant assertions in the JVM-testable domain and data layers using Kotlin assert(), which Gradle's unit-test task runs with assertions enabled (-ea) by default, so they are checked during dynamic analysis while remaining disabled in ART release builds.



    All medium and higher severity exploitable vulnerabilities discovered with dynamic code analysis MUST be fixed in a timely way after they are confirmed. [dynamic_analysis_fixed]
    If you are not running dynamic code analysis and thus have not found any vulnerabilities in this way, choose "not applicable" (N/A). A vulnerability is considered medium or higher severity if its Common Vulnerability Scoring System (CVSS) base qualitative score is medium or higher. In CVSS versions 2.0 through 3.1, this is equivalent to a CVSS score of 4.0 or higher. Projects may use the CVSS score as published in a widely-used vulnerability database (such as the National Vulnerability Database) using the most-recent version of CVSS reported in that database. Projects may instead calculate the severity themselves using the latest version of CVSS at the time of the vulnerability disclosure, if the calculation inputs are publicly revealed once the vulnerability is publicly known.

    Not applicable: the project's dynamic analysis (its instrumented and unit test runs) has not surfaced any exploitable vulnerabilities of medium or higher severity, so there are none to fix. Should any be found, the project's practice of blocking releases on failing tests means they would be addressed before the next release.



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Project badge entry owned by: Martin A. Godisch.
Entry created on 2026-07-04 04:21:04 UTC, last updated on 2026-07-14 19:16:17 UTC. Last achieved passing badge on 2026-07-04 08:45:54 UTC.