Add Enable/DisableNormalMasterSecret APIs to enforce EMS requirement at runtime. Disable server EMS when DisableExtendedMasterSecret is called, not just client EMS.

[kareem-wolfssl]

Description

Fixes zd#21980

Testing

Built-in tests plus added tests

Checklist

• added tests
• updated/added doxygen
• updated appropriate READMEs
• Updated manual and documentation

[Copilot]

Pull request overview

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Adds runtime controls to enforce TLS Extended Master Secret (EMS) usage by introducing “require EMS” behavior (via disabling the normal master secret) and ensuring server-side EMS disablement is honored, with accompanying error/message updates and new API tests.

Changes:

• Add public APIs to enable/disable “normal master secret” (effectively requiring EMS) at WOLFSSL and WOLFSSL_CTX levels.
• Make wolfSSL_DisableExtendedMasterSecret() disable EMS behavior on servers (ignore peer EMS request), not only clients.
• Add tests covering server-side EMS disable behavior and EMS-required negotiation failure.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
wolfssl/ssl.h	Exposes new public APIs for requiring/allowing standard master secret usage.
wolfssl/internal.h	Adds disableEMS / requireEMS flags to context and per-connection options.
wolfssl/error-ssl.h	Updates EMS-related error code description to match new semantics.
src/tls.c	Enforces EMS-required behavior during master secret derivation; server ignores EMS extension when disabled.
src/ssl_api_ext.c	Implements new Enable/DisableNormalMasterSecret APIs and updates DisableExtendedMasterSecret semantics.
src/internal.c	Propagates new EMS flags from CTX to SSL; updates error string; server ignores EMS when disabled in PSK path.
tests/api/test_tls_ext.h	Declares new EMS tests.
tests/api/test_tls_ext.c	Adds new EMS behavior tests and API-level tests for new functions.
tests/api.c	Registers new tests in the runner.

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[github-actions]

MemBrowse Memory Report

gcc-arm-cortex-m3

• FLASH: .text +192 B (+0.2%, 122,731 B / 262,144 B, total: 47% used)

gcc-arm-cortex-m4-openssl-compat

• FLASH: .rodata +24 B, .text +256 B (+0.0%, 769,492 B / 1,048,576 B, total: 73% used)

gcc-arm-cortex-m4-rsa-only

• FLASH: .text +256 B (+0.1%, 326,168 B / 1,048,576 B, total: 31% used)

gcc-arm-cortex-m4-tls12

• FLASH: .text +192 B (+0.2%, 123,483 B / 262,144 B, total: 47% used)

linuxkm-standard

• Data: __patchable_function_entries +32 B (+0.1%, 48,648 B)
  No memory changes detected for:
• gcc-arm-cortex-m0plus
• gcc-arm-cortex-m4
• gcc-arm-cortex-m4-baremetal
• gcc-arm-cortex-m4-crypto-only
• gcc-arm-cortex-m4-dtls13
• gcc-arm-cortex-m4-min-ecc
• gcc-arm-cortex-m4-pkcs7
• gcc-arm-cortex-m4-pq
• gcc-arm-cortex-m4-sp-math
• gcc-arm-cortex-m4-tls13
• gcc-arm-cortex-m7
• gcc-arm-cortex-m7-pq
• gcc-arm-cortex-m7-tls13
• linuxkm-pie
• stm32-sim-stm32h753

[kareem-wolfssl]

Retest this please