Soldier/base64.cpp
#include <Windows.h>
#include "base64.h"
const char base64_chars[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
char *
base64_encode(const unsigned char *input, int length)
{
int i=0, j=0, s=0;
unsigned char char_array_3[3], char_array_4[4];
int b64len = (length+2 - ((length+2)%3))*4/3;
char *b64str = (char *) malloc(b64len + 1);
if(b64str == NULL)
return NULL;
while (length--) {
char_array_3[i++] = *(input++);
if (i == 3) {
char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;
char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);
char_array_4[2] = ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);
char_array_4[3] = char_array_3[2] & 0x3f;
for (i = 0; i < 4; i++)
b64str[s++] = base64_chars[char_array_4[i]];
i = 0;
}
}
if (i) {
for (j = i; j < 3; j++)
char_array_3[j] = '\0';
char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;
char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);
char_array_4[2] = ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);
char_array_4[3] = char_array_3[2] & 0x3f;
for (j = 0; j < i + 1; j++)
b64str[s++] = base64_chars[char_array_4[j]];
while (i++ < 3)
b64str[s++] = '=';
}
b64str[b64len] = '\0';
return b64str;
}
inline bool is_base64(unsigned char c) {
return (isalnum(c) || (c == '+') || (c == '/'));
}
unsigned char *
base64_decode(const char *input, int length, int *outlen)
{
int i = 0;
int j = 0;
int r = 0;
int idx = 0;
unsigned char char_array_4[4], char_array_3[3];
unsigned char *output = (unsigned char *)malloc(length*3/4);
while (length-- && input[idx] != '=') {
//skip invalid or padding based chars
if (!is_base64(input[idx])) {
idx++;
continue;
}
char_array_4[i++] = input[idx++];
if (i == 4) {
for (i = 0; i < 4; i++)
char_array_4[i] = strchr(base64_chars, char_array_4[i]) - base64_chars;
char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);
char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];
for (i = 0; (i < 3); i++)
output[r++] = char_array_3[i];
i = 0;
}
}
if (i) {
for (j = i; j <4; j++)
char_array_4[j] = 0;
for (j = 0; j <4; j++)
char_array_4[j] = strchr(base64_chars, char_array_4[j]) - base64_chars;
char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);
char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];
for (j = 0; (j < i - 1); j++)
output[r++] = char_array_3[j];
}
*outlen = r;
return output;
}