base64.md

base64.c

/*************************************************************************
    > File Name: base64.c
    > Author: jige003
    > Created Time: Thu 25 Apr 2019 03:12:24 PM CST
 ************************************************************************/

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <assert.h>
#include <errno.h>
#include <stdint.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <openssl/evp.h>
#include <openssl/err.h>
#include <openssl/rand.h>
#include <openssl/bio.h>
#include <openssl/buffer.h>


typedef unsigned char byte;

void b64_encode(const byte *inbuf, size_t inlen, byte **outbuf, size_t *outlen){
    BIO *buff, *b64;
    BUF_MEM *ptr;

    b64 = BIO_new(BIO_f_base64());
    buff = BIO_new(BIO_s_mem());
    buff = BIO_push(b64, buff);

    BIO_set_flags(buff, BIO_FLAGS_BASE64_NO_NL);
    BIO_set_close(buff, BIO_CLOSE);
    BIO_write(buff, inbuf, inlen);
    BIO_flush(buff);

    BIO_get_mem_ptr(buff, &ptr);
    (*outlen) = ptr->length;
    (*outbuf) = BUF_strdup(ptr->data);

    BIO_free_all(buff);
}

void b64_decode(const byte *inbuf, size_t  inlen, byte **outbuf, size_t *outlen){
    BIO *buff, *b64;

    b64 = BIO_new(BIO_f_base64());
    buff = BIO_new_mem_buf((void *)inbuf, inlen);
    buff = BIO_push(b64, buff);

    BIO_set_flags(buff, BIO_FLAGS_BASE64_NO_NL);
    BIO_set_close(buff, BIO_CLOSE);
    BIO_write(buff, inbuf, inlen);
    BIO_flush(buff);

    (*outbuf) = (byte *)malloc(inlen * sizeof(byte));
    (*outlen) = BIO_read(b64, (*outbuf), inlen);
    (*outbuf) = (byte *)realloc((void*)(*outbuf), ((*outlen + 1) * sizeof(byte)));
    (*outbuf)[(*outlen)] = '\0';

    BIO_free_all(buff);

}

void xfree(void *ptr){
    if (ptr != ((void*)0)) free(ptr);
}

int main(void){
    unsigned char inbuf[] = "this is a test string";
    unsigned char *outbuf;

    size_t inlen, outlen;
    inlen = strlen(inbuf);

    unsigned char *plainbuf;
    size_t plen;



/* use to test memory leak */
#ifdef LOOP
    while(1){
#endif

    b64_encode(inbuf, inlen, &outbuf, &outlen);
    printf("inbuf:%s outbuf:%s\n", inbuf, outbuf);

    b64_decode(outbuf, outlen, &plainbuf, &plen);
    printf("base64buf:%s  plainbuf:%s\n", outbuf, plainbuf);
    assert( strcmp(plainbuf, inbuf) == 0 );
    xfree(plainbuf);
    xfree(outbuf);

#ifdef LOOP
    }
#endif
    return 0;
}

base64.md

c base64 encode/decode implement by openssl

void b64_encode(const byte *inbuf, size_t inlen, byte **outbuf, size_t *outlen);

void b64_decode(const byte *inbuf, size_t  inlen, byte **outbuf, size_t *outlen);