Compile error

[cswea3]

Error given:

base64.cpp:39:44: error: invalid conversion from ‘const void*’ to ‘void*’ [-fpermissive]
   BIO *bio = BIO_new_mem_buf(b64message, -1)

g++ --version
g++ (GCC) 4.8.5 20150623 (Red Hat 4.8.5-4)
Copyright (C) 2015 Free Software Foundation, Inc.

I fixed it on my copy but have never sent in a bug fix before so I am not sure how to.

[shanet]

Thanks for the report. I don't have that issue with GCC 6.1.1. Could you post the output of openssl version here please?

You can generate a quick diff of what you've changed by running git diff as well. Posting the output of that here will allow me to merge your fixes in without having to go through a whole pull request process (unless you want to do that, of course!).

[cswea3]

In basecode64.cpp in your base64Decode function parameters I changed it from const char *b64message to just char *b64message.

In my version of openssl bio.h and according to their wiki at https://wiki.openssl.org/index.php/Manual:BIO_s_mem%283%29

BIO_new_mem_buf takes a void* as it's first argument not const void*

openssl version

OpenSSL 1.0.1e-fips 11 Feb 2013

git diff
diff --git a/base64.cpp b/base64.cpp
index 011726e..b884374 100644
--- a/base64.cpp
+++ b/base64.cpp
@@ -27,7 +27,7 @@ char* base64Encode(const unsigned char *message, const size_t length) {
   return b64text;
 }

-int base64Decode(const char *b64message, const size_t length, unsigned char **buffer) {
+int base64Decode(char *b64message, const size_t length, unsigned char **buffer) {
   int decodedLength = calcDecodeLength(b64message, length);
   *buffer = (unsigned char*)malloc(decodedLength + 1);

[cswea3]

It seems to be a problem with BIO_new_mem_buf as it should take a const void*
Reference https://mta.openssl.org/pipermail/openssl-dev/2015-November/003299.html

[shanet]

Yup, thanks for digging that up. And the current head uses a const pointer (https://github.com/openssl/openssl/blob/5e93e5fc377ebc8bc30ffac1fa20a04cb25459eb/crypto/bio/bss_mem.c#L73) so I think I'm going to leave this as-is. If possible, you should upgrade your version of OpenSSL. 1.0.1e is quite old at this point and, most notably, is vulnerable to the Heartbleed bug.

[shanet]

I'll add a note to the README though recommending an up-to-date version of OpenSSL to avoid problems like this that others may have run into.