为什么openssl无法解码php的base64_encode函数编码的字符串？

Question

I want to base64 encode a string, and decode it in C language with OpenSSL api. I encoded in php like that:

<?php 
echo base64_encode("aaa");
?>

result is "YWFh"

Then decode it in C like that:

int base64_decode(char *str,int str_len,char *decode,int decode_buffer_len){
    int len=0;
    BIO *b64,*bmem;
    b64=BIO_new(BIO_f_base64());
    bmem=BIO_new_mem_buf(str,str_len);
    bmem=BIO_push(b64,bmem);
    len=BIO_read(bmem,decode,str_len);
    decode[len]=0;
    BIO_free_all(bmem);
    return 0;
}

result is NULL, nothing decoded.

Can't decode the string encoded before.

I tried to use these command lines to test:

$echo "aaa" | openssl enc -base64 
output: YWFhCg==

$echo "YWFhCg==" | openssl enc -base64 -d
output: aaa

What's the difference between base64_encode in php and openssl?What causes this?

Answer 1

Add BIO_set_flags(b64, BIO_FLAGS_BASE64_NO_NL) after the BIO_new() call to tell OpenSSL that all the input appears in a single line without newline.