Someone asked for an example of decoding with OpenSSL on the Howto base64 encode with C/C++ and OpenSSL post. So here it is:

[code lang=”c”]
#include

#include
#include
#include
#include
#include

char *unbase64(unsigned char *input, int length);

int main(int argc, char **argv)
{
char *output = unbase64(“WU9ZTyEA\n\0”, strlen(“WU9ZTyEA\n\0”));
printf(“Unbase64: *%s*\n”, output);
free(output);
}

char *unbase64(unsigned char *input, int length)
{
BIO *b64, *bmem;

char *buffer = (char *)malloc(length);
memset(buffer, 0, length);

b64 = BIO_new(BIO_f_base64());
bmem = BIO_new_mem_buf(input, length);
bmem = BIO_push(b64, bmem);

BIO_read(bmem, buffer, length);

BIO_free_all(bmem);

return buffer;
}
[/code]

[tags]C,C++,OpenSSL[/tags]

I’ve been doing a little C programming lately and I have found that if you have a up to date distribution of linux there are a lot of libraries out there that make doing things you do in other languages like java easier.

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