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Enforce a TLS 1.3 floor in Java sources

Recipe IDio.moderne.cryptography.pqc.EnforceTls13Java
Artifactio.moderne.recipe:rewrite-cryptography

Rewrites JSSE and BouncyCastle protocol configuration to a TLS 1.3 floor, so that JEP 527 hybrid key exchange — which exists for TLS 1.3 only — can negotiate. Covers SSLContext.getInstance algorithm literals, the setEnabledProtocols/setProtocols sinks including BCSSLParameters, same-file protocol array constants whose only readers are those sinks, the jdk.tls.client.protocols, jdk.tls.server.protocols and https.protocols system properties, and getSupportedVersions overrides on BouncyCastle TlsPeer subclasses. Surfaces that cannot be rewritten safely — an array constant shared with non-TLS code, or a Security.setProperty("jdk.tls.disabledAlgorithms", ...) call that replaces rather than extends the JDK default list — are marked and recorded as Report only rows instead of being changed. Protocol values that are not statically resolvable are left alone without a row: finding those is the discovery recipes' job, and reporting them here would duplicate their findings. Test sources are skipped by default, because a protocol test usually enables a legacy version on purpose in order to assert that it is refused. One shape deserves review before the diff is merged: a protocol list that was deliberately widened to work around a handshake failure against a legacy peer looks exactly like an unmaintained legacy floor, and narrowing it will re-break that peer. Every rewrite is recorded in the enforcement data table with its before and after protocols, and retainTls12In scopes the exception once such a site is identified.

Single recipeOpenRewriteModerne Proprietary License
Try in PlatformTry this recipe in the Moderne platform. Not a user yet? You’ll get a no-setup demo environment, with nothing to install or configure.

Options

5 parameters
5 optional
ParameterExampleTypeRequired
minimumProtocolTLSv1.2StringOptional
The protocol floor to enforce globally: TLSv1.3 (the default) strips TLSv1.2 from every enabled-protocols list, TLSv1.2 retains it everywhere. Use retainTls12In instead when only some modules need the exception. SSLContext.getInstance algorithm names are rewritten to TLSv1.3 under either setting, because the algorithm name is a *ceiling*: a TLSv1.2 context can never negotiate TLS 1.3, so a TLSv1.2 floor would otherwise be capped below the version it is meant to allow.
retainTls12In**/legacy/**ListOptional
Globs naming the sources that keep TLSv1.2 in their rewritten protocol lists, matched against both the source path and the enclosing fully qualified class name. SSLv2Hello, SSLv3, TLSv1 and TLSv1.1 are still stripped inside a matched source, and TLSv1.3 is still ensured present — the exception is for partners stuck on TLS 1.2, not for keeping a legacy floor.
rewriteContextAlgorithmBooleanOptional
Rewrite legacy SSLContext.getInstance algorithm literals — SSL, SSLv3, TLSv1, TLSv1.1, TLSv1.2, matched case-insensitively as JCA does — to TLSv1.3. On its own this is hygiene rather than enforcement, since the algorithm name only raises the ceiling; it is enforcement because this recipe rewrites the enabled-protocols lists in the same pass. Default true.
skipTestSourcesBooleanOptional
Leave test sources alone. A protocol test very often enables a legacy version on purpose so it can assert that the version is refused, so rewriting it hardens nothing and deletes the coverage that proves the hardening works. Set to false to rewrite tests as well, which is only useful once the production code is already enforced. Default true.
strictAlgorithmNameBooleanOptional
Also rewrite the version-flexible algorithm names TLS and Default to TLSv1.3. Off by default: those names already permit TLS 1.3, so changing them narrows what the JVM may negotiate without making anything post-quantum ready.

Examples

java
ParameterValue
minimumProtocolnull
retainTls12Innull
rewriteContextAlgorithmnull
skipTestSourcesnull
strictAlgorithmNamenull
Before
import javax.net.ssl.SSLEngine;
import javax.net.ssl.SSLParameters;
import javax.net.ssl.SSLServerSocket;
import javax.net.ssl.SSLSocket;

class Hardening {
void harden(SSLSocket socket, SSLServerSocket serverSocket, SSLEngine engine, SSLParameters parameters) {
socket.setEnabledProtocols(new String[]{"TLSv1.2", "TLSv1.1"});
serverSocket.setEnabledProtocols(new String[]{"TLSv1", "TLSv1.1", "TLSv1.2"});
engine.setEnabledProtocols(new String[]{"SSLv3", "TLSv1.2"});
parameters.setProtocols(new String[]{"TLSv1.2", "TLSv1.3"});
}
}
After
import javax.net.ssl.SSLEngine;
import javax.net.ssl.SSLParameters;
import javax.net.ssl.SSLServerSocket;
import javax.net.ssl.SSLSocket;

class Hardening {
void harden(SSLSocket socket, SSLServerSocket serverSocket, SSLEngine engine, SSLParameters parameters) {
socket.setEnabledProtocols(new String[]{"TLSv1.3"});
serverSocket.setEnabledProtocols(new String[]{"TLSv1.3"});
engine.setEnabledProtocols(new String[]{"TLSv1.3"});
parameters.setProtocols(new String[]{"TLSv1.3"});
}
}

Usage

Run this recipe

This recipe has no required configuration options. Users of Moderne can run it via the Moderne CLI.

You will need to have configured the Moderne CLI on your machine before you can run the following command.

shell
mod run . --recipe EnforceTls13Java

If the recipe is not available locally, then you can install it using:

RELEASE resolves to the newest release and LATEST to the newest build of any kind, including snapshots. Either one lets mod config recipes upgrade pull in later versions without editing this command; a pinned version stays where you put it.

mod config recipes jar install io.moderne.recipe:rewrite-cryptography:RELEASE

Data tables

TLS protocol enforcement
io.moderne.cryptography.pqc.table.ProtocolEnforcementTable

Protocol configuration surfaces rewritten to a TLS 1.3 floor, and surfaces flagged as needing manual review because rewriting them would change behaviour in a way a source scan cannot justify. Rows describe declared configuration only: a JVM's java.security file, container -D flags and environment variables are invisible here, so an enforced source does not prove an enforced runtime.

ColumnDescription
Configuration surfaceThe API or configuration key that produced the row, e.g. SSLContext.getInstance, SSLSocket.setEnabledProtocols, SSLServerSocket.setEnabledProtocols, SSLEngine.setEnabledProtocols, SSLParameters.setProtocols, https.protocols, jdk.tls.client.protocols, jdk.tls.server.protocols, jdk.tls.disabledAlgorithms, AbstractTlsPeer.getSupportedVersions, server.ssl.enabled-protocols, server.ssl.protocol. The token vocabulary is shared with the TLS configuration inventory so discovery and enforcement rows can be joined.
ActionRewritten when the recipe changed the source, or Report only when the surface was flagged but deliberately not transformed — a protocol array shared with non-TLS code, or a jdk.tls.disabledAlgorithms assignment that replaces rather than extends the JDK default list.
Protocols beforeComma-joined protocol tokens found before the change, e.g. TLSv1.1,TLSv1.2. BouncyCastle downTo ranges are expanded to their JSSE spelling, e.g. TLSv1.2,TLSv1.1,TLSv1. For a jdk.tls.disabledAlgorithms row this is the raw property value.
Protocols afterComma-joined protocol tokens after the change, e.g. TLSv1.3, or TLSv1.3,TLSv1.2 where an exception retains TLS 1.2. Empty for Report only rows.
Code snippetThe source code of the detected API usage, e.g. Cipher.getInstance("DES").
Library nameThe library providing the configuration surface: JSSE, BouncyCastle or Spring Boot.
Library languageThe language of the source the row was found in: Java, Properties or YAML.
File locationThe path of the source file relative to the repository root.
Start line1-based line of the start of the API usage.
Start column0-based column of the start of the API usage, or -1 when unavailable.
Start offset0-based character offset of the start of the API usage, or -1 when unavailable.
End line1-based line of the end of the API usage.
End column0-based column of the end of the API usage, or -1 when unavailable.
End offset0-based character offset of the end of the API usage, or -1 when unavailable.
Repository nameThe repository name from Git provenance, e.g. payment-service. Empty when unknown.
Scan sourceWhere the source was scanned from, derived from Git provenance, e.g. GitHub, GitLab, Local Repository.
BranchThe branch from Git provenance, e.g. main. Empty when unknown.
Source files that had results
org.openrewrite.table.SourcesFileResults

Source files that were modified by the recipe run.

ColumnDescription
Source path before the runThe source path of the file before the run. null when a source file was created during the run.
Source path after the runA recipe may modify the source path. This is the path after the run. null when a source file was deleted during the run.
Parent of the recipe that made changesIn a hierarchical recipe, the parent of the recipe that made a change. Empty if this is the root of a hierarchy or if the recipe is not hierarchical at all.
Recipe that made changesThe specific recipe that made a change.
Estimated time savingAn estimated effort that a developer to fix manually instead of using this recipe, in unit of seconds.
CycleThe recipe cycle in which the change was made.
Source files that had search results
org.openrewrite.table.SearchResults

Search results that were found during the recipe run.

ColumnDescription
Source path of search result before the runThe source path of the file with the search result markers present.
Source path of search result after run the runA recipe may modify the source path. This is the path after the run. null when a source file was deleted during the run.
ResultThe trimmed printed tree of the LST element that the marker is attached to.
DescriptionThe content of the description of the marker.
Recipe that added the search markerThe specific recipe that added the Search marker.
Source files that errored on a recipe
org.openrewrite.table.SourcesFileErrors

The details of all errors produced by a recipe run.

ColumnDescription
Source pathThe file that failed to parse.
Recipe that made changesThe specific recipe that made a change.
Stack traceThe stack trace of the failure.
Recipe performance
org.openrewrite.table.RecipeRunStats

Statistics used in analyzing the performance of recipes.

ColumnDescription
The recipeThe recipe whose stats are being measured both individually and cumulatively.
Source file countThe number of source files the recipe ran over.
Source file changed countThe number of source files which were changed in the recipe run. Includes files created, deleted, and edited.
Cumulative scanning time (ns)The total time spent across the scanning phase of this recipe.
Max scanning time (ns)The max time scanning any one source file.
Cumulative edit time (ns)The total time spent across the editing phase of this recipe.
Max edit time (ns)The max time editing any one source file.