Fix broken XDC in case of enabled TLS encryption. UT added.

[dcherednik]

Changelog entry

The issue was missed checks for enabled encryption during zero copy routine. It causes attempt to send data unencrypted via XDC socket.
#18546

Changelog category

• Bugfix

Description for reviewers

Fix bug appears from 08dc695

[github-actions]

🟢 2025-05-22 17:07:29 UTC The validation of the Pull Request description is successful.

[github-actions]

⚪ 2025-05-22 17:05:21 UTC Pre-commit check linux-x86_64-relwithdebinfo for 51d5694 has started.
⚪ 2025-05-22 17:05:32 UTC Artifacts will be uploaded here
⚪ 2025-05-22 17:08:32 UTC ya make is running...
🔴 2025-05-22 17:10:18 UTC Build failed, see the logs. Also see fail summary

[github-actions]

⚪ 2025-05-22 17:05:31 UTC Pre-commit check linux-x86_64-release-asan for 51d5694 has started.
⚪ 2025-05-22 17:05:42 UTC Artifacts will be uploaded here
⚪ 2025-05-22 17:08:36 UTC ya make is running...
🔴 2025-05-22 17:10:31 UTC Build failed, see the logs. Also see fail summary

[github-actions]

⚪ 2025-05-22 17:20:46 UTC Pre-commit check linux-x86_64-release-asan for 240319b has started.
⚪ 2025-05-22 17:21:18 UTC Artifacts will be uploaded here
⚪ 2025-05-22 17:25:01 UTC ya make is running...
🟡 2025-05-22 18:59:06 UTC Some tests failed, follow the links below. This fail is not in blocking policy yet Going to retry failed tests...

Test history | Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
15183	14993	0	122	41	27

⚪ 2025-05-22 19:00:32 UTC ya make is running... (failed tests rerun, try 2)
🟡 2025-05-22 19:32:46 UTC Some tests failed, follow the links below. This fail is not in blocking policy yet Going to retry failed tests...

Test history | Ya make output | Test bloat | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
1566 (only retried tests)	1465	0	58	18	25

⚪ 2025-05-22 19:33:03 UTC ya make is running... (failed tests rerun, try 3)
🟡 2025-05-22 20:04:34 UTC Some tests failed, follow the links below. This fail is not in blocking policy yet

Test history | Ya make output | Test bloat | Test bloat | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
1189 (only retried tests)	1091	0	50	27	21

🟢 2025-05-22 20:04:50 UTC Build successful.
🟢 2025-05-22 20:05:23 UTC ydbd size 3.9 GiB changed* by 0 Bytes, which is <= 0 Bytes vs main: OK

ydbd size dash	main: 6cb271e	merge: 240319b	diff	diff %
ydbd size	4 145 501 336 Bytes	4 145 501 336 Bytes	0 Bytes	0.000%
ydbd stripped size	1 439 190 296 Bytes	1 439 190 296 Bytes	0 Bytes	0.000%

^{*please be aware that the difference is based on comparing your commit and the last completed build from the post-commit, check comparation}

[github-actions]

⚪ 2025-05-22 17:28:49 UTC Pre-commit check linux-x86_64-relwithdebinfo for 240319b has started.
⚪ 2025-05-22 17:29:12 UTC Artifacts will be uploaded here
⚪ 2025-05-22 17:32:48 UTC ya make is running...
🟡 2025-05-22 18:47:13 UTC Some tests failed, follow the links below. Going to retry failed tests...

Test history | Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
30221	27524	0	6	2647	44

⚪ 2025-05-22 18:49:48 UTC ya make is running... (failed tests rerun, try 2)
🟢 2025-05-22 19:18:15 UTC Tests successful.

Test history | Ya make output | Test bloat | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
941 (only retried tests)	905	0	0	4	32

🟢 2025-05-22 19:18:27 UTC Build successful.
🟢 2025-05-22 19:18:48 UTC ydbd size 2.2 GiB changed* by +32 Bytes, which is < 100.0 KiB vs main: OK

ydbd size dash	main: 6cb271e	merge: 240319b	diff	diff %
ydbd size	2 357 264 368 Bytes	2 357 264 400 Bytes	+32 Bytes	+0.000%
ydbd stripped size	495 229 832 Bytes	495 229 832 Bytes	0 Bytes	0.000%

^{*please be aware that the difference is based on comparing your commit and the last completed build from the post-commit, check comparation}