137 lines
4.2 KiB
C++
137 lines
4.2 KiB
C++
/*
|
|
base64.cpp and base64.h
|
|
|
|
base64 encoding and decoding with C++.
|
|
|
|
Version: 1.02.00
|
|
|
|
Copyright (C) 2004-2017, 2020 René Nyffenegger
|
|
|
|
This source code is provided 'as-is', without any express or implied
|
|
warranty. In no event will the author be held liable for any damages
|
|
arising from the use of this software.
|
|
|
|
Permission is granted to anyone to use this software for any purpose,
|
|
including commercial applications, and to alter it and redistribute it
|
|
freely, subject to the following restrictions:
|
|
|
|
1. The origin of this source code must not be misrepresented; you must not
|
|
claim that you wrote the original source code. If you use this source code
|
|
in a product, an acknowledgment in the product documentation would be
|
|
appreciated but is not required.
|
|
|
|
2. Altered source versions must be plainly marked as such, and must not be
|
|
misrepresented as being the original source code.
|
|
|
|
3. This notice may not be removed or altered from any source distribution.
|
|
|
|
René Nyffenegger rene.nyffenegger@adp-gmbh.ch
|
|
|
|
*/
|
|
|
|
#include "base64.hpp"
|
|
#include <cctype>
|
|
|
|
static const std::string base64_chars =
|
|
"ABCDEFGHIJKLMNOPQRSTUVWXYZ"
|
|
"abcdefghijklmnopqrstuvwxyz"
|
|
"0123456789+/";
|
|
|
|
static std::size_t pos_of_char(const unsigned char chr) {
|
|
//
|
|
// Return the position of chr within base64_chars.
|
|
//
|
|
|
|
if (chr >= 'A' && chr <= 'Z') return chr - 'A';
|
|
else if (chr >= 'a' && chr <= 'z') return chr - 'a' + ('Z' - 'A') + 1;
|
|
else if (chr >= '0' && chr <= '9') return chr - '0' + ('Z' - 'A') + ('z' - 'a') + 2;
|
|
else if (chr == '+' ) return 62;
|
|
else if (chr == '/' ) return 63;
|
|
|
|
throw "If input is correct, this line should never be reached.";
|
|
}
|
|
|
|
static inline bool is_base64(unsigned char c) {
|
|
return (isalnum(c) || (c == '+') || (c == '/'));
|
|
}
|
|
|
|
std::string base64_encode(unsigned char const* bytes_to_encode, unsigned int in_len) {
|
|
std::string ret;
|
|
int i = 0;
|
|
unsigned char char_array_3[3];
|
|
unsigned char char_array_4[4];
|
|
|
|
while (in_len--) {
|
|
char_array_3[i++] = *(bytes_to_encode++);
|
|
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++)
|
|
ret.push_back(base64_chars[char_array_4[i]]);
|
|
i = 0;
|
|
}
|
|
}
|
|
|
|
if (i)
|
|
{
|
|
for(int 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);
|
|
|
|
for (int j = 0; (j < i + 1); j++)
|
|
ret.push_back(base64_chars[char_array_4[j]]);
|
|
|
|
while((i++ < 3))
|
|
ret.push_back('=');
|
|
}
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
std::string base64_decode(std::string const& encoded_string) {
|
|
size_t in_len = encoded_string.size();
|
|
int i = 0;
|
|
int in_ = 0;
|
|
unsigned char char_array_4[4], char_array_3[3];
|
|
std::string ret;
|
|
|
|
ret.reserve(encoded_string.size() / 4 * 3);
|
|
|
|
while (in_len-- && ( encoded_string[in_] != '=') && is_base64(encoded_string[in_])) {
|
|
char_array_4[i++] = encoded_string[in_]; in_++;
|
|
if (i ==4) {
|
|
for (i = 0; i <4; i++) {
|
|
char_array_4[i] = pos_of_char(char_array_4[i]);
|
|
}
|
|
|
|
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++)
|
|
ret.push_back(char_array_3[i]);
|
|
i = 0;
|
|
}
|
|
}
|
|
|
|
if (i) {
|
|
for (int j = 0; j < i; j++) {
|
|
char_array_4[j] = pos_of_char(char_array_4[j]);
|
|
}
|
|
|
|
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);
|
|
|
|
for (int j = 0; (j < i - 1); j++)
|
|
ret.push_back(char_array_3[j]);
|
|
}
|
|
|
|
return ret;
|
|
} |