HADOOP-19931. Summary: SSLHostnameVerifier subject CN parsing is too brittle (#8584)

[steveloughran]

JUnit4 version

Co-authored by Claude Code

Contributed by Steve Loughran

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• Object storage: have the integration tests been executed and the endpoint declared according to the connector-specific documentation?
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[steveloughran]

already tested locally; will merge if yetus is happy (and ignoring checkstyle failure)

[hadoop-yetus]

🎊 +1 overall

Vote	Subsystem	Runtime	Logfile	Comment
+0 🆗	reexec	18m 48s		Docker mode activated.
			_ Prechecks _
+1 💚	dupname	0m 0s		No case conflicting files found.
+0 🆗	codespell	0m 0s		codespell was not available.
+0 🆗	detsecrets	0m 0s		detect-secrets was not available.
+1 💚	@author	0m 0s		The patch does not contain any @author tags.
+1 💚	test4tests	0m 0s		The patch appears to include 1 new or modified test files.
			_ branch-3.4 Compile Tests _
+1 💚	mvninstall	53m 51s		branch-3.4 passed
+1 💚	compile	19m 6s		branch-3.4 passed with JDK Ubuntu-11.0.27+6-post-Ubuntu-0ubuntu120.04
+1 💚	compile	17m 21s		branch-3.4 passed with JDK Private Build-1.8.0_452-8u452-gaus1-0ubuntu120.04-b09
+1 💚	checkstyle	1m 19s		branch-3.4 passed
+1 💚	mvnsite	1m 36s		branch-3.4 passed
+1 💚	javadoc	1m 22s		branch-3.4 passed with JDK Ubuntu-11.0.27+6-post-Ubuntu-0ubuntu120.04
+1 💚	javadoc	1m 52s		branch-3.4 passed with JDK Private Build-1.8.0_452-8u452-gaus1-0ubuntu120.04-b09
+1 💚	spotbugs	2m 33s		branch-3.4 passed
+1 💚	shadedclient	40m 36s		branch has no errors when building and testing our client artifacts.
			_ Patch Compile Tests _
+1 💚	mvninstall	1m 0s		the patch passed
+1 💚	compile	18m 21s		the patch passed with JDK Ubuntu-11.0.27+6-post-Ubuntu-0ubuntu120.04
+1 💚	javac	18m 21s		the patch passed
+1 💚	compile	17m 25s		the patch passed with JDK Private Build-1.8.0_452-8u452-gaus1-0ubuntu120.04-b09
+1 💚	javac	17m 25s		the patch passed
+1 💚	blanks	0m 0s		The patch has no blanks issues.
-0 ⚠️	checkstyle	1m 17s	/results-checkstyle-hadoop-common-project_hadoop-common.txt	hadoop-common-project/hadoop-common: The patch generated 17 new + 282 unchanged - 9 fixed = 299 total (was 291)
+1 💚	mvnsite	1m 36s		the patch passed
+1 💚	javadoc	1m 18s		the patch passed with JDK Ubuntu-11.0.27+6-post-Ubuntu-0ubuntu120.04
+1 💚	javadoc	1m 54s		the patch passed with JDK Private Build-1.8.0_452-8u452-gaus1-0ubuntu120.04-b09
+1 💚	spotbugs	2m 39s		the patch passed
+1 💚	shadedclient	39m 50s		patch has no errors when building and testing our client artifacts.
			_ Other Tests _
+1 💚	unit	19m 9s		hadoop-common in the patch passed.
+1 💚	asflicense	1m 5s		The patch does not generate ASF License warnings.
		265m 48s

Subsystem	Report/Notes
Docker	ClientAPI=1.55 ServerAPI=1.55 base: https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-8591/1/artifact/out/Dockerfile
GITHUB PR	#8591
Optional Tests	dupname asflicense compile javac javadoc mvninstall mvnsite unit shadedclient spotbugs checkstyle codespell detsecrets
uname	Linux c25e1643edda 5.15.0-181-generic #191-Ubuntu SMP Fri May 22 19:09:02 UTC 2026 x86_64 x86_64 x86_64 GNU/Linux
Build tool	maven
Personality	dev-support/bin/hadoop.sh
git revision	branch-3.4 / fbffe65
Default Java	Private Build-1.8.0_452-8u452-gaus1-0ubuntu120.04-b09
Multi-JDK versions	/usr/lib/jvm/java-11-openjdk-amd64:Ubuntu-11.0.27+6-post-Ubuntu-0ubuntu120.04 /usr/lib/jvm/java-8-openjdk-amd64:Private Build-1.8.0_452-8u452-gaus1-0ubuntu120.04-b09
Test Results	https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-8591/1/testReport/
Max. process+thread count	1251 (vs. ulimit of 5500)
modules	C: hadoop-common-project/hadoop-common U: hadoop-common-project/hadoop-common
Console output	https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-8591/1/console
versions	git=2.25.1 maven=3.6.3 spotbugs=4.2.2
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