Add BN_bn2binpad API and enable OpenVPN master CI testing

[julek-wolfssl]

No description provided.

[Copilot]

Pull request overview

Note

Copilot was unable to run its full agentic suite in this review.

Adds OpenSSL-compatible BN_bn2binpad support to wolfSSL’s OpenSSL shim layer and updates the OpenVPN GitHub Actions workflow to test against OpenVPN master again now that the API exists.

Changes:

• Added wolfSSL_BN_bn2binpad declaration + BN_bn2binpad macro mapping.
• Implemented wolfSSL_BN_bn2binpad with left-zero-padding semantics and size checks.
• Expanded BN API tests and updated OpenVPN CI matrix to include master.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
wolfssl/openssl/bn.h	Exposes wolfSSL_BN_bn2binpad and maps BN_bn2binpad to it.
src/ssl_bn.c	Implements wolfSSL_BN_bn2binpad encoding/padding behavior.
tests/api/test_ossl_bn.c	Adds coverage for BN_bn2binpad success/error cases.
.github/workflows/openvpn.yml	Re-enables testing against OpenVPN master in CI matrix.

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[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated no new comments.

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[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

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[Copilot]

The API contract in the comment says this function returns -1 on error, but the implementation returns WOLFSSL_FATAL_ERROR. This works only if WOLFSSL_FATAL_ERROR is guaranteed to be -1 across all builds/configurations. To keep OpenSSL-compat behavior explicit and stable, return -1 directly (or ensure WOLFSSL_FATAL_ERROR is definitionally -1 for this API surface).

[Copilot]

sizeof(padOut) is a size_t but BN_bn2binpad takes an int length. Some toolchains treat this as a sign-conversion warning (and in general it’s safer to avoid implicit narrowing). Consider casting explicitly, e.g. (int)sizeof(padOut), for the test calls that pass sizeof(...).

Suggested change

	ExpectIntEQ(BN_bn2binpad(NULL, padOut, sizeof(padOut)), -1);
	ExpectIntEQ(BN_bn2binpad(&emptyBN, padOut, sizeof(padOut)), -1);
	ExpectIntEQ(BN_bn2binpad(a, NULL, sizeof(padOut)), -1);
	ExpectIntEQ(BN_bn2binpad(NULL, padOut, (int)sizeof(padOut)), -1);
	ExpectIntEQ(BN_bn2binpad(&emptyBN, padOut, (int)sizeof(padOut)), -1);
	ExpectIntEQ(BN_bn2binpad(a, NULL, (int)sizeof(padOut)), -1);

[Copilot]

The workflow comment says ignore_words_list should be sorted alphabetically (case sensitive). Adding toLen at the end breaks that rule; please insert it in sorted order to keep the list maintainable and consistent with the documented expectation.

Suggested change

	ignore_words_list: adin,aNULL,brunch,carryIn,chainG,ciph,cLen,cliKs,dout,haveA,inCreated,inOut,inout,larg,LEAPYEAR,Merget,optionA,parm,parms,repid,rIn,userA,ser,siz,te,Te,HSI,failT,toLen,
	ignore_words_list: adin,aNULL,brunch,carryIn,chainG,ciph,cLen,cliKs,dout,haveA,inCreated,inOut,inout,larg,LEAPYEAR,Merget,optionA,parm,parms,repid,rIn,ser,siz,te,toLen,userA,Te,HSI,failT,