X509v3 Certificate Generation Support (WolfSSLCertificate)

[cconlon]

This PR adds X.509v3 certificate generation support to native wolfSSL JNI wrappers, exposed through the com.wolfssl.WolfSSLCertificate class. Note this is not inside the JSSE provider, and is a wolfSSL-specific API that closely wraps the native WOLFSSL_X509 certificate generation capabilities.

An example has been added which does both self-signed and CA-signed certificate generation (./examples/X509v3CertificateGeneration.java). Generated certificates are output in PEM and DER format under the directory ./examples/certs/generated). This is compiled when ant examples is run:

$ cd wolfssljni
$ ant examples
$ ./examples/X509v3CertificateGeneration.sh

JUnit test cases have also been added to test both self-signed and CA-signed certificate generation.

Other changes in this PR include:

• Addition of Windows batch scripts to more easily run ProviderTest and X509v3CertificateGeneration examples.
• Updated Visual Studio project to add new files
• Updates example certificates to match current wolfssl master certs

[JacobBarthelmeh]

Running the new example appeared to fail for me. Is there more options needed when compiling wolfSSL than just --enable-jni?

$ ./examples/X509v3CertificateGeneration.sh 
wolfSSL JNI X509v3 Certificate Generation Example

Generating self-signed cert using filescom.wolfssl.WolfSSLException: Error setting extension into native WOLFSSL_X509 (ret: 0)
	at com.wolfssl.WolfSSLCertificate.addExtension(WolfSSLCertificate.java:759)
	at X509v3CertificateGeneration.generateSelfSignedUsingFiles(X509v3CertificateGeneration.java:199)
	at X509v3CertificateGeneration.run(X509v3CertificateGeneration.java:665)
	at X509v3CertificateGeneration.main(X509v3CertificateGeneration.java:683)

Example passed

Verifying certs with openssl...
Testing each can be opened with openssl x509 -text
Can't open ../certs/generated/*.der for reading, No such file or directory
4427615680:error:02001002:system library:fopen:No such file or directory:crypto/bio/bss_file.c:72:fopen('../certs/generated/*.der','rb')
4427615680:error:2006D080:BIO routines:BIO_new_file:no such file:crypto/bio/bss_file.c:79:
unable to load certificate
File not readable with openssl x509: ../certs/generated/*.der

[cconlon]

@JacobBarthelmeh The additions in this PR are partially dependent on the fixes made to native wolfSSL post-5.6.3 (wolfSSL/wolfssl#6585). The fixes are specifically needed for use of setting the Key Usage and Extended Key Usage extension when generating a certificate.

I force pushed some additions here to wrap our native wolfSSL_lib_version_hex() and return a more helpful exception message for users on 5.6.3 or earlier.