lwIP: require TLS certificate verification when CA is configured

[Old-Ding]

why to submit this PR

ALTCP TLS client configurations should require server certificate verification when a CA certificate is configured. This keeps certificate validation in the TLS configuration layer and makes the configured trust anchor effective.

what is your solution

Use MBEDTLS_SSL_VERIFY_REQUIRED for client TLS configurations that provide a CA certificate. Keep the existing optional verification mode for server configurations and client configurations without a CA certificate to preserve current compatibility.

provide the config and bsp

• BSP: bsp/bouffalo_lab/bl808/m0
• .config: CONFIG_RT_USING_LWIP212=y, CONFIG_PKG_USING_MBEDTLS=y
• action: no fork action run was available after pushing the branch

validation

• git diff --check
• static source check confirmed both altcp_tls_create_config_client() and altcp_tls_create_config_client_2wayauth() use the shared client configuration path
• scons -j4 in bsp/bouffalo_lab/bl808/m0 did not reach compilation because the configured toolchain path /opt/Xuantie-900-gcc-elf-newlib-x86_64-V2.6.1/bin is not available on this Windows host

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[github-actions]

📌 Code Review Assignment

🏷️ Tag: components

Reviewers: Maihuanyi

Changed Files (Click to expand)

• components/net/lwip/lwip-2.1.2/src/apps/altcp_tls/altcp_tls_mbedtls.c

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📊 Current Review Status (Last Updated: 2026-06-28 01:05 CST)

• ⌛ Maihuanyi Pending Review

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