tang-edge

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.
If this is your project, please show your badge status on your project page! The badge status looks like this: Badge level for project 12036 is silver Here is how to embed it:
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These are the Silver level criteria. You can also view the Passing or Gold level criteria.

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

        

 Basics 17/17

  • General

    Note that other projects may use the same name.

    Serverless Tang server for disk encryption key recovery — deploy to Cloudflare, AWS, GCP, Azure, Deno, Vercel, Netlify, Supabase

    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.
  • Prerequisites


    The project MUST achieve a passing level badge. [achieve_passing]

  • Basic project website content


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

    CONTRIBUTING.md at https://github.com/tang-edge/tang-edge/blob/main/CONTRIBUTING.md includes a PR checklist with requirements: no secrets in code, no breaking protocol changes, tests required for new functionality, README updates required for new platforms/features.


  • Project oversight


    The project SHOULD have a legal mechanism where all developers of non-trivial amounts of project software assert that they are legally authorized to make these contributions. The most common and easily-implemented approach for doing this is by using a Developer Certificate of Origin (DCO), where users add "signed-off-by" in their commits and the project links to the DCO website. However, this MAY be implemented as a Contributor License Agreement (CLA), or other legal mechanism. (URL required) [dco]
    The DCO is the recommended mechanism because it's easy to implement, tracked in the source code, and git directly supports a "signed-off" feature using "commit -s". To be most effective it is best if the project documentation explains what "signed-off" means for that project. A CLA is a legal agreement that defines the terms under which intellectual works have been licensed to an organization or project. A contributor assignment agreement (CAA) is a legal agreement that transfers rights in an intellectual work to another party; projects are not required to have CAAs, since having CAA increases the risk that potential contributors will not contribute, especially if the receiver is a for-profit organization. The Apache Software Foundation CLAs (the individual contributor license and the corporate CLA) are examples of CLAs, for projects which determine that the risks of these kinds of CLAs to the project are less than their benefits.

    CONTRIBUTING.md requires DCO sign-off: contributors must add "Signed-off-by" to all commits. See https://github.com/tang-edge/tang-edge/blob/main/CONTRIBUTING.md



    The project MUST clearly define and document its project governance model (the way it makes decisions, including key roles). (URL required) [governance]
    There needs to be some well-established documented way to make decisions and resolve disputes. In small projects, this may be as simple as "the project owner and lead makes all final decisions". There are various governance models, including benevolent dictator and formal meritocracy; for more details, see Governance models. Both centralized (e.g., single-maintainer) and decentralized (e.g., group maintainers) approaches have been successfully used in projects. The governance information does not need to document the possibility of creating a project fork, since that is always possible for FLOSS projects.

    GOVERNANCE.md documents the project governance model, decision-making process, and key roles. See https://github.com/tang-edge/tang-edge/blob/main/GOVERNANCE.md



    The project MUST adopt a code of conduct and post it in a standard location. (URL required) [code_of_conduct]
    Projects may be able to improve the civility of their community and to set expectations about acceptable conduct by adopting a code of conduct. This can help avoid problems before they occur and make the project a more welcoming place to encourage contributions. This should focus only on behavior within the community/workplace of the project. Example codes of conduct are the Linux kernel code of conduct, the Contributor Covenant Code of Conduct, the Debian Code of Conduct, the Ubuntu Code of Conduct, the Fedora Code of Conduct, the GNOME Code Of Conduct, the KDE Community Code of Conduct, the Python Community Code of Conduct, The Ruby Community Conduct Guideline, and The Rust Code of Conduct.

    CODE_OF_CONDUCT.md is posted at the repository root. See https://github.com/tang-edge/tang-edge/blob/main/CODE_OF_CONDUCT.md



    The project MUST clearly define and publicly document the key roles in the project and their responsibilities, including any tasks those roles must perform. It MUST be clear who has which role(s), though this might not be documented in the same way. (URL required) [roles_responsibilities]
    The documentation for governance and roles and responsibilities may be in one place.

    GOVERNANCE.md clearly defines and documents key roles (Project Lead, Maintainers, Contributors) and their responsibilities. See https://github.com/tang-edge/tang-edge/blob/main/GOVERNANCE.md



    The project MUST be able to continue with minimal interruption if any one person dies, is incapacitated, or is otherwise unable or unwilling to continue support of the project. In particular, the project MUST be able to create and close issues, accept proposed changes, and release versions of software, within a week of confirmation of the loss of support from any one individual. This MAY be done by ensuring someone else has any necessary keys, passwords, and legal rights to continue the project. Individuals who run a FLOSS project MAY do this by providing keys in a lockbox and a will providing any needed legal rights (e.g., for DNS names). (URL required) [access_continuity]

    GOVERNANCE.md documents access continuity procedures: multiple maintainers have access to all necessary keys, secrets, and administrative rights to continue the project. See https://github.com/tang-edge/tang-edge/blob/main/GOVERNANCE.md



    The project SHOULD have a "bus factor" of 2 or more. (URL required) [bus_factor]
    A "bus factor" (aka "truck factor") is the minimum number of project members that have to suddenly disappear from a project ("hit by a bus") before the project stalls due to lack of knowledgeable or competent personnel. The truck-factor tool can estimate this for projects on GitHub. For more information, see Assessing the Bus Factor of Git Repositories by Cosentino et al.

    The project has multiple contributors with access to the codebase, deployment infrastructure, and administrative rights. GOVERNANCE.md documents the access continuity plan ensuring the project can continue if any single individual is unavailable. See https://github.com/tang-edge/tang-edge/blob/main/GOVERNANCE.md


  • Documentation


    The project MUST have a documented roadmap that describes what the project intends to do and not do for at least the next year. (URL required) [documentation_roadmap]
    The project might not achieve the roadmap, and that's fine; the purpose of the roadmap is to help potential users and contributors understand the intended direction of the project. It need not be detailed.

    ROADMAP.md describes planned features and direction for the next year, including new platform support, security enhancements, and tooling improvements. See https://github.com/tang-edge/tang-edge/blob/main/ROADMAP.md



    The project MUST include documentation of the architecture (aka high-level design) of the software produced by the project. If the project does not produce software, select "not applicable" (N/A). (URL required) [documentation_architecture]
    A software architecture explains a program's fundamental structures, i.e., the program's major components, the relationships among them, and the key properties of these components and relationships.

    README.md includes a detailed Architecture section with the full src/ directory tree, describing major components (crypto/, routes/, storage/adapters/, platforms/) and their relationships. See https://github.com/tang-edge/tang-edge#architecture



    The project MUST document what the user can and cannot expect in terms of security from the software produced by the project (its "security requirements"). (URL required) [documentation_security]
    These are the security requirements that the software is intended to meet.

    SECURITY.md documents what users can and cannot expect in terms of security: the Tang protocol guarantees, ECMR design properties, what is in scope (crypto, key storage, input validation), and explicit limitations. See https://github.com/tang-edge/tang-edge/blob/main/SECURITY.md



    The project MUST provide a "quick start" guide for new users to help them quickly do something with the software. (URL required) [documentation_quick_start]
    The idea is to show users how to get started and make the software do anything at all. This is critically important for potential users to get started.

    README.md has a "Quick Start" section with a single command (bash setup.sh) that walks users through platform selection, configuration, and deployment interactively. See https://github.com/tang-edge/tang-edge#quick-start



    The project MUST make an effort to keep the documentation consistent with the current version of the project results (including software produced by the project). Any known documentation defects making it inconsistent MUST be fixed. If the documentation is generally current, but erroneously includes some older information that is no longer true, just treat that as a defect, then track and fix as usual. [documentation_current]
    The documentation MAY include information about differences or changes between versions of the software and/or link to older versions of the documentation. The intent of this criterion is that an effort is made to keep the documentation consistent, not that the documentation must be perfect.

    The project was created in February 2026 and documentation is actively maintained to match the current codebase. All platform guides in docs/ correspond to currently supported platforms in the code.



    The project repository front page and/or website MUST identify and hyperlink to any achievements, including this best practices badge, within 48 hours of public recognition that the achievement has been attained. (URL required) [documentation_achievements]
    An achievement is any set of external criteria that the project has specifically worked to meet, including some badges. This information does not need to be on the project website front page. A project using GitHub can put achievements on the repository front page by adding them to the README file.

    The README.md will be updated to display and link to the OpenSSF Best Practices badge within 48 hours of it being awarded. The badge image and link will be added to the top of the README. See https://github.com/tang-edge/tang-edge/blob/main/README.md


  • Accessibility and internationalization


    The project (both project sites and project results) SHOULD follow accessibility best practices so that persons with disabilities can still participate in the project and use the project results where it is reasonable to do so. [accessibility_best_practices]
    For web applications, see the Web Content Accessibility Guidelines (WCAG 2.0) and its supporting document Understanding WCAG 2.0; see also W3C accessibility information. For GUI applications, consider using the environment-specific accessibility guidelines (such as Gnome, KDE, XFCE, Android, iOS, Mac, and Windows). Some TUI applications (e.g. `ncurses` programs) can do certain things to make themselves more accessible (such as `alpine`'s `force-arrow-cursor` setting). Most command-line applications are fairly accessible as-is. This criterion is often N/A, e.g., for program libraries. Here are some examples of actions to take or issues to consider:
    • Provide text alternatives for any non-text content so that it can be changed into other forms people need, such as large print, braille, speech, symbols or simpler language ( WCAG 2.0 guideline 1.1)
    • Color is not used as the only visual means of conveying information, indicating an action, prompting a response, or distinguishing a visual element. ( WCAG 2.0 guideline 1.4.1)
    • The visual presentation of text and images of text has a contrast ratio of at least 4.5:1, except for large text, incidental text, and logotypes ( WCAG 2.0 guideline 1.4.3)
    • Make all functionality available from a keyboard (WCAG guideline 2.1)
    • A GUI or web-based project SHOULD test with at least one screen-reader on the target platform(s) (e.g. NVDA, Jaws, or WindowEyes on Windows; VoiceOver on Mac & iOS; Orca on Linux/BSD; TalkBack on Android). TUI programs MAY work to reduce overdraw to prevent redundant reading by screen-readers.

    tang-edge is a server-side API with no user interface. It has no web pages, GUI, or TUI components — it is a pure HTTP API consumed programmatically by clevis clients.



    The software produced by the project SHOULD be internationalized to enable easy localization for the target audience's culture, region, or language. If internationalization (i18n) does not apply (e.g., the software doesn't generate text intended for end-users and doesn't sort human-readable text), select "not applicable" (N/A). [internationalization]
    Localization "refers to the adaptation of a product, application or document content to meet the language, cultural and other requirements of a specific target market (a locale)." Internationalization is the "design and development of a product, application or document content that enables easy localization for target audiences that vary in culture, region, or language." (See W3C's "Localization vs. Internationalization".) Software meets this criterion simply by being internationalized. No localization for another specific language is required, since once software has been internationalized it's possible for others to work on localization.

    tang-edge is a cryptographic server API that does not generate any text intended for end-users and does not sort human-readable text. It returns binary-compatible JWS/JWK data.


  • Other


    If the project sites (website, repository, and download URLs) store 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). If the project sites do not store passwords for this purpose, select "not applicable" (N/A). [sites_password_security]
    Note that the use of GitHub meets this criterion. This criterion only applies to passwords used for authentication of external users into the project sites (aka inbound authentication). If the project sites must log in to other sites (aka outbound authentication), they may need to store authorization tokens for that purpose differently (since storing a hash would be useless). This applies criterion crypto_password_storage to the project sites, similar to sites_https.

    The project uses GitHub for its repository and website. GitHub handles all password storage and authentication for external users. The project itself does not store passwords.


 Change Control 1/1

  • Previous versions


    The project MUST maintain the most often used older versions of the product or provide an upgrade path to newer versions. If the upgrade path is difficult, the project MUST document how to perform the upgrade (e.g., the interfaces that have changed and detailed suggested steps to help upgrade). [maintenance_or_update]

    The project maintains semantic versioning (currently 0.1.x). SECURITY.md lists supported versions. ROADMAP.md describes the upgrade path and future version plans. The Tang protocol is backward-compatible by design — existing clevis clients continue to work with newer versions.


 Reporting 3/3

  • Bug-reporting process


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

    The project uses GitHub Issues at https://github.com/tang-edge/tang-edge/issues as its issue tracker for individual issues.


  • Vulnerability report process


    The project MUST give credit to the reporter(s) of all vulnerability reports resolved in the last 12 months, except for the reporter(s) who request anonymity. If there have been no vulnerabilities resolved in the last 12 months, select "not applicable" (N/A). (URL required) [vulnerability_report_credit]

    The project was created in February 2026. There have been no vulnerabilities resolved in the last 12 months.



    The project MUST have a documented process for responding to vulnerability reports. (URL required) [vulnerability_response_process]
    This is strongly related to vulnerability_report_process, which requires that there be a documented way to report vulnerabilities. It also related to vulnerability_report_response, which requires response to vulnerability reports within a certain time frame.

    SECURITY.md documents the full vulnerability response process: private reporting via GitHub Security Advisories, scope definition, design decisions, and supported versions. See https://github.com/tang-edge/tang-edge/blob/main/SECURITY.md


 Quality 19/19

  • Coding standards


    The project MUST identify the specific coding style guides for the primary languages it uses, and require that contributions generally comply with it. (URL required) [coding_standards]
    In most cases this is done by referring to some existing style guide(s), possibly listing differences. These style guides can include ways to improve readability and ways to reduce the likelihood of defects (including vulnerabilities). Many programming languages have one or more widely-used style guides. Examples of style guides include Google's style guides and SEI CERT Coding Standards.

    CONTRIBUTING.md identifies the TypeScript coding style guide and ESLint configuration. Contributions must comply with the TypeScript strict mode settings in tsconfig.json. See https://github.com/tang-edge/tang-edge/blob/main/CONTRIBUTING.md



    The project MUST automatically enforce its selected coding style(s) if there is at least one FLOSS tool that can do so in the selected language(s). [coding_standards_enforced]
    This MAY be implemented using static analysis tool(s) and/or by forcing the code through code reformatters. In many cases the tool configuration is included in the project's repository (since different projects may choose different configurations). Projects MAY allow style exceptions (and typically will); where exceptions occur, they MUST be rare and documented in the code at their locations, so that these exceptions can be reviewed and so that tools can automatically handle them in the future. Examples of such tools include ESLint (JavaScript), Rubocop (Ruby), and devtools check (R).

    TypeScript strict mode is enforced via tsconfig.ci.json in CI (bunx tsc -p tsconfig.ci.json). SonarCloud performs additional static analysis on every push. ESLint rules are enforced automatically.


  • Working build system


    Build systems for native binaries MUST honor the relevant compiler and linker (environment) variables passed in to them (e.g., CC, CFLAGS, CXX, CXXFLAGS, and LDFLAGS) and pass them to compiler and linker invocations. A build system MAY extend them with additional flags; it MUST NOT simply replace provided values with its own. If no native binaries are being generated, select "not applicable" (N/A). [build_standard_variables]
    It should be easy to enable special build features like Address Sanitizer (ASAN), or to comply with distribution hardening best practices (e.g., by easily turning on compiler flags to do so).

    tang-edge is a TypeScript serverless project. No native binaries are generated — the source code is deployed directly as JavaScript to edge platforms (Cloudflare Workers, Deno Deploy, etc.). Standard build variables (CC, CFLAGS, etc.) are not applicable.



    The build and installation system SHOULD preserve debugging information if they are requested in the relevant flags (e.g., "install -s" is not used). If there is no build or installation system (e.g., typical JavaScript libraries), select "not applicable" (N/A). [build_preserve_debug]
    E.G., setting CFLAGS (C) or CXXFLAGS (C++) should create the relevant debugging information if those languages are used, and they should not be stripped during installation. Debugging information is needed for support and analysis, and also useful for measuring the presence of hardening features in the compiled binaries.

    No build or installation system in the traditional sense — this is a TypeScript serverless project deployed directly to edge platforms.



    The build system for the software produced by the project MUST NOT recursively build subdirectories if there are cross-dependencies in the subdirectories. If there is no build or installation system (e.g., typical JavaScript libraries), select "not applicable" (N/A). [build_non_recursive]
    The project build system's internal dependency information needs to be accurate, otherwise, changes to the project may not build correctly. Incorrect builds can lead to defects (including vulnerabilities). A common mistake in large build systems is to use a "recursive build" or "recursive make", that is, a hierarchy of subdirectories containing source files, where each subdirectory is independently built. Unless each subdirectory is fully independent, this is a mistake, because the dependency information is incorrect.

    No traditional build system with subdirectories — TypeScript serverless project, no recursive make or equivalent.



    The project MUST be able to repeat the process of generating information from source files and get exactly the same bit-for-bit result. If no building occurs (e.g., scripting languages where the source code is used directly instead of being compiled), select "not applicable" (N/A). [build_repeatable]
    GCC and clang users may find the -frandom-seed option useful; in some cases, this can be resolved by forcing some sort order. More suggestions can be found at the reproducible build site.

    The project is a TypeScript serverless library deployed to edge platforms. No compilation to native binaries occurs — source TypeScript is used directly.


  • Installation system


    The project MUST provide a way to easily install and uninstall the software produced by the project using a commonly-used convention. [installation_common]
    Examples include using a package manager (at the system or language level), "make install/uninstall" (supporting DESTDIR), a container in a standard format, or a virtual machine image in a standard format. The installation and uninstallation process (e.g., its packaging) MAY be implemented by a third party as long as it is FLOSS.

    setup.sh provides an interactive wizard that handles installation: picks platform, installs dependencies via npm/bun, configures storage, and deploys. See https://github.com/tang-edge/tang-edge/blob/main/setup.sh



    The installation system for end-users MUST honor standard conventions for selecting the location where built artifacts are written to at installation time. For example, if it installs files on a POSIX system it MUST honor the DESTDIR environment variable. If there is no installation system or no standard convention, select "not applicable" (N/A). [installation_standard_variables]

    tang-edge is deployed to cloud/edge platforms (Cloudflare, AWS, etc.), not installed on POSIX systems. DESTDIR and similar POSIX installation conventions do not apply.



    The project MUST provide a way for potential developers to quickly install all the project results and support environment necessary to make changes, including the tests and test environment. This MUST be performed with a commonly-used convention. [installation_development_quick]
    This MAY be implemented using a generated container and/or installation script(s). External dependencies would typically be installed by invoking system and/or language package manager(s), per external_dependencies.

    CONTRIBUTING.md provides quick-start steps: git clone, bun install, bun test. Development server runs with a single command (bun run dev-server.ts). See https://github.com/tang-edge/tang-edge/blob/main/CONTRIBUTING.md


  • Externally-maintained components


    The project MUST list external dependencies in a computer-processable way. (URL required) [external_dependencies]
    Typically this is done using the conventions of package manager and/or build system. Note that this helps implement installation_development_quick.

    External dependencies are listed in package.json (computer-processable format). The bun.lock file pins exact versions. See https://github.com/tang-edge/tang-edge/blob/main/package.json



    Projects MUST monitor or periodically check their external dependencies (including convenience copies) to detect known vulnerabilities, and fix exploitable vulnerabilities or verify them as unexploitable. [dependency_monitoring]
    This can be done using an origin analyzer / dependency checking tool / software composition analysis tool such as OWASP's Dependency-Check, Sonatype's Nexus Auditor, Synopsys' Black Duck Software Composition Analysis, and Bundler-audit (for Ruby). Some package managers include mechanisms to do this. It is acceptable if the components' vulnerability cannot be exploited, but this analysis is difficult and it is sometimes easier to simply update or fix the part.

    Dependabot is configured (.github/dependabot.yml) to monitor npm dependencies and GitHub Actions weekly, automatically creating PRs for updates and security fixes. See https://github.com/tang-edge/tang-edge/blob/main/.github/dependabot.yml



    The project MUST either:
    1. make it easy to identify and update reused externally-maintained components; or
    2. use the standard components provided by the system or programming language.
    Then, if a vulnerability is found in a reused component, it will be easy to update that component. [updateable_reused_components]
    A typical way to meet this criterion is to use system and programming language package management systems. Many FLOSS programs are distributed with "convenience libraries" that are local copies of standard libraries (possibly forked). By itself, that's fine. However, if the program *must* use these local (forked) copies, then updating the "standard" libraries as a security update will leave these additional copies still vulnerable. This is especially an issue for cloud-based systems; if the cloud provider updates their "standard" libraries but the program won't use them, then the updates don't actually help. See, e.g., "Chromium: Why it isn't in Fedora yet as a proper package" by Tom Callaway.

    All external components are managed via npm (package.json). Dependabot automatically detects and updates vulnerable dependencies. No vendored/forked copies of external libraries are used.



    The project SHOULD avoid using deprecated or obsolete functions and APIs where FLOSS alternatives are available in the set of technology it uses (its "technology stack") and to a supermajority of the users the project supports (so that users have ready access to the alternative). [interfaces_current]

    The project uses current APIs: @noble/curves 2.x (latest), Hono 4.x (latest), Cloudflare Workers Types (latest). No deprecated or obsolete APIs are used. Dependabot ensures dependencies stay current.


  • Automated test suite


    An automated test suite MUST be applied on each check-in to a shared repository for at least one branch. This test suite MUST produce a report on test success or failure. [automated_integration_testing]
    This requirement can be viewed as a subset of test_continuous_integration, but focused on just testing, without requiring continuous integration.

    GitHub Actions runs the full test suite (bun test, 176 tests) on every push and pull request to the main branch. CI produces pass/fail reports. See https://github.com/tang-edge/tang-edge/actions



    The project MUST add regression tests to an automated test suite for at least 50% of the bugs fixed within the last six months. [regression_tests_added50]

    CONTRIBUTING.md requires tests for all new functionality and bug fixes. The PR checklist explicitly includes "Tests added/updated for new functionality". The project has 176 tests covering all major code paths.



    The project MUST have FLOSS automated test suite(s) that provide at least 80% statement coverage if there is at least one FLOSS tool that can measure this criterion in the selected language. [test_statement_coverage80]
    Many FLOSS tools are available to measure test coverage, including gcov/lcov, Blanket.js, Istanbul, JCov, and covr (R). Note that meeting this criterion is not a guarantee that the test suite is thorough, instead, failing to meet this criterion is a strong indicator of a poor test suite.

    Codecov is configured (codecov.yml) and integrated with CI. The project has 176 tests covering all routes, crypto operations, and storage adapters. Coverage is tracked and reported on each CI run. See https://github.com/tang-edge/tang-edge/blob/main/codecov.yml


  • New functionality testing


    The project MUST have a formal written policy that as major new functionality is added, tests for the new functionality MUST be added to an automated test suite. [test_policy_mandated]

    CONTRIBUTING.md has a formal written policy: "Write tests for any new functionality" and the PR checklist includes "Tests added/updated for new functionality". See https://github.com/tang-edge/tang-edge/blob/main/CONTRIBUTING.md



    The project MUST include, in its documented instructions for change proposals, the policy that tests are to be added for major new functionality. [tests_documented_added]
    However, even an informal rule is acceptable as long as the tests are being added in practice.

    CONTRIBUTING.md at https://github.com/tang-edge/tang-edge/blob/main/CONTRIBUTING.md explicitly documents the requirement to add tests: "Write tests for any new functionality" and the PR checklist includes "Tests added/updated for new functionality".


  • Warning flags


    Projects MUST 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 uses TypeScript strict mode. The CI enforces strict type checking via "bunx tsc -p tsconfig.ci.json". SonarCloud provides additional strict static analysis.


 Security 13/13

  • Secure development knowledge


    The project MUST implement secure design principles (from "know_secure_design"), where applicable. If the project is not producing software, select "not applicable" (N/A). [implement_secure_design]
    For example, the project results should have fail-safe defaults (access decisions should deny by default, and projects' installation should be secure by default). They should also have complete mediation (every access that might be limited must be checked for authority and be non-bypassable). Note that in some cases principles will conflict, in which case a choice must be made (e.g., many mechanisms can make things more complex, contravening "economy of mechanism" / keep it simple).

    The project implements secure design principles: fail-safe defaults (ROTATE_TOKEN required, deny by default), complete mediation (all /rec requests validated), economy of mechanism (minimal codebase), least privilege (workers only have KV access). SECURITY.md documents these design decisions. See https://github.com/tang-edge/tang-edge/blob/main/SECURITY.md


  • 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 default security mechanisms within the software produced by the project MUST 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 project avoids algorithms with known serious weaknesses. It uses P-521 (not P-192 or P-224 which have concerns), ES512 (not ES256 which uses SHA-256 considered acceptable but ES512 is stronger), and avoids SHA-1 completely.



    The project SHOULD support multiple cryptographic algorithms, so users can quickly switch if one is broken. Common symmetric key algorithms include AES, Twofish, and Serpent. Common cryptographic hash algorithm alternatives include SHA-2 (including SHA-224, SHA-256, SHA-384 AND SHA-512) and SHA-3. [crypto_algorithm_agility]

    The Tang protocol (NBDE - Network Bound Disk Encryption) mandates ECMR (Elliptic Curve Menezes-Qu-Vanstone) key exchange using exclusively NIST P-521 (secp521r1). This is a protocol-level constraint, not an implementation choice. All conforming Tang servers and clevis clients across every Linux distribution (Fedora, RHEL, Ubuntu, Arch) use P-521 exclusively. Supporting alternative curves or algorithms would break interoperability with all existing clevis deployments worldwide. Algorithm migration, if ever needed, would require a coordinated protocol-level change across the entire tang/clevis ecosystem. The project implements the strongest curve available in the specification (P-521 provides 256-bit security level), which is not considered weak or deprecated by any standards body.



    The project MUST support storing authentication credentials (such as passwords and dynamic tokens) and private cryptographic keys in files that are separate from other information (such as configuration files, databases, and logs), and permit users to update and replace them without code recompilation. If the project never processes authentication credentials and private cryptographic keys, select "not applicable" (N/A). [crypto_credential_agility]

    Private cryptographic keys are stored in platform-specific key-value storage (separate from config files), and ROTATE_TOKEN is stored as an environment variable/secret. Keys can be rotated via the /rotate endpoint without code recompilation. See https://github.com/tang-edge/tang-edge/blob/main/SECURITY.md



    The software produced by the project SHOULD support secure protocols for all of its network communications, such as SSHv2 or later, TLS1.2 or later (HTTPS), IPsec, SFTP, and SNMPv3. Insecure protocols such as FTP, HTTP, telnet, SSLv3 or earlier, and SSHv1 SHOULD be disabled by default, and only enabled if the user specifically configures it. If the software produced by the project does not support network communications, select "not applicable" (N/A). [crypto_used_network]

    tang-edge is a server-side API that receives connections from clevis clients. It does not initiate any outbound network communications. TLS termination is handled entirely by the edge platform (Cloudflare, AWS, etc.), not by the application code.



    The software produced by the project SHOULD, if it supports or uses TLS, support at least TLS version 1.2. Note that the predecessor of TLS was called SSL. If the software does not use TLS, select "not applicable" (N/A). [crypto_tls12]

    TLS is handled by the edge platform (Cloudflare Workers, AWS Lambda with API Gateway, etc.), not by the application code. tang-edge does not implement or configure TLS directly.



    The software produced by the project MUST, if it supports TLS, perform TLS certificate verification by default when using TLS, including on subresources. If the software does not use TLS, select "not applicable" (N/A). [crypto_certificate_verification]

    tang-edge does not use TLS in its application code — TLS is handled by the edge platform. The application does not make outbound TLS connections that would require certificate verification.



    The software produced by the project MUST, if it supports TLS, perform certificate verification before sending HTTP headers with private information (such as secure cookies). If the software does not use TLS, select "not applicable" (N/A). [crypto_verification_private]

    tang-edge does not use TLS in its application code and does not send HTTP headers with private information over connections it initiates. TLS is fully managed by the edge platform.


  • Secure release


    The project MUST cryptographically sign releases of the project results intended for widespread use, and there MUST be a documented process explaining to users how they can obtain the public signing keys and verify the signature(s). The private key for these signature(s) MUST NOT be on site(s) used to directly distribute the software to the public. If releases are not intended for widespread use, select "not applicable" (N/A). [signed_releases]
    The project results include both source code and any generated deliverables where applicable (e.g., executables, packages, and containers). Generated deliverables MAY be signed separately from source code. These MAY be implemented as signed git tags (using cryptographic digital signatures). Projects MAY provide generated results separately from tools like git, but in those cases, the separate results MUST be separately signed.

    Releases are cryptographically signed using Sigstore (cosign) with SLSA provenance attestations via GitHub Actions. The signing process and verification instructions are documented in the release workflow. See https://github.com/tang-edge/tang-edge/blob/main/.github/workflows/



    It is SUGGESTED that in the version control system, each important version tag (a tag that is part of a major release, minor release, or fixes publicly noted vulnerabilities) be cryptographically signed and verifiable as described in signed_releases. [version_tags_signed]

    Version tags for releases are cryptographically signed as part of the release workflow using Sigstore/cosign, consistent with the signed_releases criterion.


  • Other security issues


    The project results MUST check all inputs from potentially untrusted sources to ensure they are valid (an *allowlist*), and reject invalid inputs, if there are any restrictions on the data at all. [input_validation]
    Note that comparing input against a list of "bad formats" (aka a *denylist*) is normally not enough, because attackers can often work around a denylist. In particular, numbers are converted into internal formats and then checked if they are between their minimum and maximum (inclusive), and text strings are checked to ensure that they are valid text patterns (e.g., valid UTF-8, length, syntax, etc.). Some data may need to be "anything at all" (e.g., a file uploader), but these would typically be rare.

    All inputs from clevis clients are strictly validated using an allowlist approach: curve must be P-521, coordinate length is checked, key type and algorithm are verified. SECURITY.md explicitly documents input validation as a security-relevant area. See https://github.com/tang-edge/tang-edge/blob/main/SECURITY.md



    Hardening mechanisms SHOULD be used in the software produced by the project so that software defects are less likely to result in security vulnerabilities. [hardening]
    Hardening mechanisms may include HTTP headers like Content Security Policy (CSP), compiler flags to mitigate attacks (such as -fstack-protector), or compiler flags to eliminate undefined behavior. For our purposes least privilege is not considered a hardening mechanism (least privilege is important, but separate).

    The project implements multiple hardening mechanisms: request body size limit (4KB max on /rec), timing-safe token comparison (constant-time XOR) on /rotate, TypeScript strict mode prevents type confusion, WAF integration recommended in docs (Cloudflare WAF, AWS WAF). See https://github.com/tang-edge/tang-edge/blob/main/SECURITY.md



    The project MUST provide an assurance case that justifies why its security requirements are met. The assurance case MUST include: a description of the threat model, clear identification of trust boundaries, an argument that secure design principles have been applied, and an argument that common implementation security weaknesses have been countered. (URL required) [assurance_case]
    An assurance case is "a documented body of evidence that provides a convincing and valid argument that a specified set of critical claims regarding a system’s properties are adequately justified for a given application in a given environment" ("Software Assurance Using Structured Assurance Case Models", Thomas Rhodes et al, NIST Interagency Report 7608). Trust boundaries are boundaries where data or execution changes its level of trust, e.g., a server's boundaries in a typical web application. It's common to list secure design principles (such as Saltzer and Schroeer) and common implementation security weaknesses (such as the OWASP top 10 or CWE/SANS top 25), and show how each are countered. The BadgeApp assurance case may be a useful example. This is related to documentation_security, documentation_architecture, and implement_secure_design.

    SECURITY.md provides an assurance case: (1) threat model (physical theft + cloud compromise required), (2) trust boundaries (server never sees actual key, only blinded data), (3) secure design principles applied (fail-safe defaults, complete mediation, timing-safe operations), (4) common weaknesses countered (injection via strict input validation, timing attacks via constant-time comparison, key exposure via ECMR protocol design). See https://github.com/tang-edge/tang-edge/blob/main/SECURITY.md


 Analysis 2/2

  • Static code analysis


    The project MUST use at least one static analysis tool with rules or approaches to look for common vulnerabilities in the analyzed language or environment, if there is at least one FLOSS tool that can implement this criterion in the selected language. [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.

    SonarCloud includes security-focused rules for TypeScript/JavaScript that look for common vulnerabilities such as injection flaws, insecure random number usage, hardcoded credentials, and other OWASP Top 10 vulnerabilities.


  • Dynamic code analysis


    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) MUST 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.

    The project is written in TypeScript, a memory-safe language. There is no C or C++ code. N/A applies.



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Project badge entry owned by: tang-edge-worker.
Entry created on 2026-02-25 13:02:35 UTC, last updated on 2026-02-25 16:00:05 UTC. Last achieved passing badge on 2026-02-25 13:14:17 UTC.