tls: openssl: output: configurable certstore name

[cosmo0920]

To support loading certificates with a user-specified name from Windows CertStore, we need to provide a capability to handle input and output parameters for specifying name of certstore and loading certstore with a user-defined name.

Fixes #9215.

This is also a possible obstacles migrations from Fluentd to Fluent Bit.
So, we should eliminate this kind of blockers for migrations.

Plus, this is a parity for Fluentd's feature:
(Fluentd does, https://docs.fluentd.org/output/forward#how-to-connect-to-a-tls-ssl-enabled-server-with-windows-certstore-certificate).

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Testing
Before we can approve your change; please submit the following in a comment:

• Example configuration file for the change

[SERVICE]
    Flush        5
    Daemon       Off
    Log_Level    debug
    HTTP_Monitor Off
    HTTP_Port    2020

[INPUT]
    Name dummy
    Tag test
    Dummy {"this is":"dummy data"}
    Rate 1

[OUTPUT]
    Name forward
    Match *
    tls on
    tls.windows.certstore_name My
    tls.windows.use_enterprise_store false

• Debug log output from testing the change

Fluent Bit v4.1.0
* Copyright (C) 2015-2025 The Fluent Bit Authors
* Fluent Bit is a CNCF sub-project under the umbrella of Fluentd
* https://fluentbit.io

______ _                  _    ______ _ _             ___  _____
|  ___| |                | |   | ___ (_) |           /   ||  _  |
| |_  | |_   _  ___ _ __ | |_  | |_/ /_| |_  __   __/ /| || |/' |
|  _| | | | | |/ _ \ '_ \| __| | ___ \ | __| \ \ / / /_| ||  /| |
| |   | | |_| |  __/ | | | |_  | |_/ / | |_   \ V /\___  |\ |_/ /
\_|   |_|\__,_|\___|_| |_|\__| \____/|_|\__|   \_/     |_(_)___/


[2025/07/15 23:56:35] [ info] Configuration:
[2025/07/15 23:56:35] [ info]  flush time     | 5.000000 seconds
[2025/07/15 23:56:35] [ info]  grace          | 5 seconds
[2025/07/15 23:56:35] [ info]  daemon         | 0
[2025/07/15 23:56:35] [ info] ___________
[2025/07/15 23:56:35] [ info]  inputs:
[2025/07/15 23:56:35] [ info]      dummy
[2025/07/15 23:56:35] [ info] ___________
[2025/07/15 23:56:35] [ info]  filters:
[2025/07/15 23:56:35] [ info] ___________
[2025/07/15 23:56:35] [ info]  outputs:
[2025/07/15 23:56:35] [ info]      forward.0
[2025/07/15 23:56:35] [ info] ___________
[2025/07/15 23:56:35] [ info]  collectors:
[2025/07/15 23:56:35] [ info] [fluent bit] version=4.1.0, commit=ea38ae232a, pid=38088
[2025/07/15 23:56:35] [debug] [engine] maxstdio set: 512
[2025/07/15 23:56:35] [debug] [engine] coroutine stack size: 98302 bytes (96.0K)
[2025/07/15 23:56:35] [ info] [storage] ver=1.5.3, type=memory, sync=normal, checksum=off, max_chunks_up=128
[2025/07/15 23:56:35] [ info] [simd    ] disabled
[2025/07/15 23:56:35] [ info] [cmetrics] version=1.0.4
[2025/07/15 23:56:35] [ info] [ctraces ] version=0.6.6
[2025/07/15 23:56:35] [ info] [input:dummy:dummy.0] initializing
[2025/07/15 23:56:35] [ info] [input:dummy:dummy.0] storage_strategy='memory' (memory only)
[2025/07/15 23:56:35] [debug] [dummy:dummy.0] created event channels: read=824 write=828
[2025/07/15 23:56:35] [debug] [forward:forward.0] created event channels: read=832 write=836
[2025/07/15 23:56:35] [debug] [tls] successfully loaded certificates from windows system Root store.
[2025/07/15 23:56:35] [debug] [output forward.0] starting to load My certstore in TLS context
[2025/07/15 23:56:35] [debug] [output forward.0] attempting to load My certstore in TLS context
[2025/07/15 23:56:35] [debug] [tls] successfully loaded certificates from windows system My store.
[2025/07/15 23:56:35] [ info] [sp] stream processor started
[2025/07/15 23:56:35] [ info] [output:forward:forward.0] worker #0 started
[2025/07/15 23:56:35] [ info] [output:forward:forward.0] worker #1 started
[2025/07/15 23:56:35] [ info] [engine] Shutdown Grace Period=5, Shutdown Input Grace Period=2
[2025/07/15 23:56:40] [debug] [task] created task=000002B5A7A71B10 id=0 OK
[2025/07/15 23:56:40] [debug] [output:forward:forward.0] task_id=0 assigned to thread #0
[2025/07/15 23:56:40] [debug] [output:forward:forward.0] request 164 bytes to flush
[2025/07/15 23:56:40] [debug] [upstream] KA connection #1180 to 127.0.0.1:24224 is connected
[2025/07/15 23:56:40] [debug] [upstream] KA connection #1180 to 127.0.0.1:24224 is now available
[2025/07/15 23:56:40] [debug] [out flush] cb_destroy coro_id=0
[2025/07/15 23:56:40] [debug] [task] destroy task=000002B5A7A71B10 (task_id=0)
[2025/07/15 23:56:42] [engine] caught signal (SIGINT)
[2025/07/15 23:56:42] [debug] [task] created task=000002B5A7A70C10 id=0 OK
[2025/07/15 23:56:42] [debug] [output:forward:forward.0] request 123 bytes to flush
[2025/07/15 23:56:42] [debug] [output:forward:forward.0] task_id=0 assigned to thread #1
[2025/07/15 23:56:42] [ warn] [engine] service will shutdown in max 5 seconds
[2025/07/15 23:56:42] [debug] [engine] retry=0000000000000000 for task 0 already scheduled to run, not re-scheduling it.
[2025/07/15 23:56:42] [ info] [input] pausing dummy.0
[2025/07/15 23:56:42] [debug] [upstream] KA connection #1116 to 127.0.0.1:24224 is connected
[2025/07/15 23:56:42] [debug] [upstream] KA connection #1116 to 127.0.0.1:24224 is now available
[2025/07/15 23:56:42] [debug] [out flush] cb_destroy coro_id=0
[2025/07/15 23:56:42] [debug] [task] destroy task=000002B5A7A70C10 (task_id=0)
[2025/07/15 23:56:43] [ info] [engine] service has stopped (0 pending tasks)
[2025/07/15 23:56:43] [ info] [input] pausing dummy.0
[2025/07/15 23:56:43] [ info] [output:forward:forward.0] thread worker #0 stopping...
[2025/07/15 23:56:43] [ info] [output:forward:forward.0] thread worker #0 stopped
[2025/07/15 23:56:43] [ info] [output:forward:forward.0] thread worker #1 stopping...
[2025/07/15 23:56:43] [ info] [output:forward:forward.0] thread worker #1 stopped

• Attached Valgrind output that shows no leaks or memory corruption was found

If this is a change to packaging of containers or native binaries then please confirm it works for all targets.

• Run local packaging test showing all targets (including any new ones) build.
• Set ok-package-test label to test for all targets (requires maintainer to do).

Documentation

• Documentation required for this feature

#10590

Backporting

• Backport to latest stable release.

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