C ++与Java中的md5 base64编码器

Question

I have a cross-language problem regarding md5 :). I have this code in Java:

BASE64Encoder encoder = new BASE64Encoder();
MessageDigest md = MessageDigest.getInstance("MD5");
md.update(someString.getBytes());
byte[] bMac = md.digest();
String anotherString = encoder.encodeBuffer(bMac);

This encodes and hashes a string in md5 and base64. A string like "aaa&1" becomes Fv4eRn4R0/mB+uc4j1GGaA==

Now the problem is: how to do this in C++? I'm using openssl/md5.h, but like any other online md5 encoder (after a small google search), it gets a hash like: 16fe1e467e11d3f981fae7388f518668

Which is in hex it seems. If I try to transform the md5 hash in base64, I get a completely different hash (longer and uglier :) ).

Help!!!

Thank you!

LE: I use the MD5 method from openssl/md5.h, as AZI pointed out.

Answer 1

Here is the C++ code to obtain md5

#include <openssl/md5.h>
unsigned char *MD5(const unsigned char *d, 
               unsigned long n,
               unsigned char *md);

example:

unsigned char inbuf[] = "aaa&1";
unsigned char outbuf[20];
MD5(inbuf, strlen(inbuf), outbuf);

for (i = 0; i < 20; i++) {
    printf("%02x ", outbuf[i]);
}

if Hex of 16fe1e467e11d3f981fae7388f518668 converted to Base64 then Hex to Base64 you will get Fv4eRn4R0/mB+uc4j1GGaA==

May refer to Howto base64 encode with C/C++ and OpenSSL to encode this to Base64

Answer 2

The solution is to use everything Azi and Mike Seymour said... So, to obtain the MD5 hash, you have to use the solution presented by Azi. Then the thing in Java uses something like Mike suggested... it encodes in base64 from binary.

My solution was to look at the code from the link provided by Azi:

http://tomeko.net/online_tools/hex_to_base64.php?lang=en

And to port it into C++. Fortunately it wasn't that hard to do... If anyone wants the C++ code, leave a comment. Thank you all!