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/* base64.cpp and base64.h Copyright (C) 2004-2008 Ren?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. Ren?Nyffenegger rene.nyffenegger@adp-gmbh.ch */ #include "base64.h" #include <iostream> static const std::string base64_chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZ" "abcdefghijklmnopqrstuvwxyz" "0123456789+/"; 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, j = 0; unsigned char char_array_3[3], 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 += 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++) ret += base64_chars[char_array_4[j]]; while((i++ < 3)) ret += '='; } return ret; } std::string base64_decode(std::string const& encoded_string) { int in_len = encoded_string.size(); int i = 0, j = 0, in_ = 0; unsigned char char_array_4[4], char_array_3[3]; std::string ret; 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] = base64_chars.find(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 += 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] = base64_chars.find(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); char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3]; for (j = 0; (j < i - 1); j++) ret += char_array_3[j]; } return ret; } int ANSIToBase64(const char *szInANSI, int nInLen, char *szOutBase64, int nOutLen) { //Input Parameter validation if ((szInANSI == NULL) || (nInLen == 0) || (szOutBase64 == NULL) || (nOutLen == 0)) return 0; if (nOutLen < (nInLen*4/3 + 1 + nInLen*4/3/BASE64_MAXLINE*2 + 1 + 4)) return 0; //Set up the parameters prior to the main encoding loop int nInPos = 0; int nOutPos = 0; int nLineLen = 0; int c1, c2, c3; int i; // Get three characters at a time from the input buffer and encode them for (i=0; i<nInLen/3; ++i) { //Get the next 2 characters c1 = szInANSI[nInPos++] & 0xFF; c2 = szInANSI[nInPos++] & 0xFF; c3 = szInANSI[nInPos++] & 0xFF; //Encode into the 4 6 bit characters szOutBase64[nOutPos++] = BASE64_TAB[c1 >> 2]; szOutBase64[nOutPos++] = BASE64_TAB[((c1 << 4) | (c2 >> 4)) & 0x3F]; szOutBase64[nOutPos++] = BASE64_TAB[((c2 << 2) | (c3 >> 6)) & 0x3F]; szOutBase64[nOutPos++] = BASE64_TAB[c3 & 0x3F]; nLineLen += 4; //Handle the case where we have gone over the max line boundary if (nLineLen > BASE64_MAXLINE - 4) { szOutBase64[nOutPos++] = EOL[0]; szOutBase64[nOutPos++] = EOL[1]; nLineLen = 0; } } // Encode the remaining one or two characters in the input buffer switch (nInLen % 3) { case 0: { szOutBase64[nOutPos++] = EOL[0]; szOutBase64[nOutPos++] = EOL[1]; break; } case 1: { c1 = szInANSI[nInPos] & 0xFF; szOutBase64[nOutPos++] = BASE64_TAB[(c1 & 0xFC) >> 2]; szOutBase64[nOutPos++] = BASE64_TAB[((c1 & 0x03) << 4)]; szOutBase64[nOutPos++] = '='; szOutBase64[nOutPos++] = '='; szOutBase64[nOutPos++] = EOL[0]; szOutBase64[nOutPos++] = EOL[1]; break; } case 2: { c1 = szInANSI[nInPos++] & 0xFF; c2 = szInANSI[nInPos] & 0xFF; szOutBase64[nOutPos++] = BASE64_TAB[(c1 & 0xFC) >> 2]; szOutBase64[nOutPos++] = BASE64_TAB[((c1 & 0x03) << 4) | ((c2 & 0xF0) >> 4)]; szOutBase64[nOutPos++] = BASE64_TAB[((c2 & 0x0F) << 2)]; szOutBase64[nOutPos++] = '='; szOutBase64[nOutPos++] = EOL[0]; szOutBase64[nOutPos++] = EOL[1]; break; } default: { return 0; } } szOutBase64[nOutPos] = 0; return nOutPos; }