get_peer_certificate error when using wolfSSL - c

Question

I'm new to using wolfSSL. I am trying to compile a set of codes using gcc.
gcc -o main main.c -lwolfssl
I encounter an error of main.c:(.text+0x47b): undefined reference to 'wolfSSL_get_peer_certificate'
collect2: error: ld returned 1 exit status upon entering the statement.
A snippet of the code shows the error location:
fprintf(stderr, "ERROR: failed to connect to wolfSSL\n");
return -1;
}
ret = certverify(CERT_FILE,verifyCert);
WOLFSSL_X509* webCert = wolfSSL_get_peer_certificate(ssl);
I have tried modifying the WOLFSSL_X509* webCert = wolfSSL_get_peer_certificate(ssl); command but it seems to be correct.
I am not too sure why this error is occuring. Can someone please help me with this?
I am using Kali Linux 2019.4 to compile this set of codes.

Answer 1

#wolfSSL_new,
It sounds like the application is failing to link the library so while the right headers are in place to locate the function definitions the final step to link the function is what is failing. Where is libwolfssl.so or libwolfssl.a located on your system? Is it in /usr/local/lib/libwolfssl.so or /usr/local/lib/libwolfssl.a?
(.a is a static library, .so is a shared object library it can be either or)
Once you located where it is try this build command instead (For the sake of an example I am going to assume it is in /usr/local/lib):
gcc main.c -o main -I/usr/local/include -L/usr/local/lib -lwolfssl
Let me know if that resolves the linker error you are seeing.
[UPDATE]
This was resolved by adding the configure setting --enable-opensslextra
[END UPDATE]
Regards,
K