pdns/base64.cc

   1 /*
   2  * This file is part of PowerDNS or dnsdist.
   3  * Copyright -- PowerDNS.COM B.V. and its contributors
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of version 2 of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * In addition, for the avoidance of any doubt, permission is granted to
  10  * link this program with OpenSSL and to (re)distribute the binaries
  11  * produced as the result of such linking.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  21  */
  22 #ifdef HAVE_CONFIG_H
  23 #include "config.h"
  24 #endif
  25 #include "base64.hh"
  26 #include <stdexcept>
  27 #include <boost/scoped_array.hpp>
  28 #include <openssl/bio.h>
  29 #include <openssl/evp.h>
  30
  31 template<typename Container> int B64Decode(const std::string& src, Container& dst)
  32 {
  33   if (src.empty() ) {
  34     dst.clear();
  35     return 0;
  36   }
  37   int dlen = ( src.length() * 6 + 7 ) / 8 ;
  38   ssize_t olen = 0;
  39   dst.resize(dlen);
  40   BIO *bio, *b64;
  41   bio = BIO_new(BIO_s_mem());
  42   BIO_write(bio, src.c_str(), src.length());
  43   b64 = BIO_new(BIO_f_base64());
  44   bio = BIO_push(b64, bio);
  45   BIO_set_flags(bio, BIO_FLAGS_BASE64_NO_NL);
  46   olen = BIO_read(b64, &dst.at(0), dlen);
  47   if ((olen == 0 || olen == -1) && BIO_should_retry(bio)) {
  48     BIO_free_all(bio);
  49     throw std::runtime_error("BIO_read failed to read all data from memory buffer");
  50   }
  51   BIO_free_all(bio);
  52   if (olen > 0) {
  53     dst.resize(olen);
  54     return 0;
  55   }
  56   return -1;
  57 }
  58
  59 template int B64Decode<std::string>(const std::string& strInput, std::string& strOutput);
  60
  61 std::string Base64Encode(const std::string& src)
  62 {
  63   if (!src.empty()) {
  64     size_t olen = 0;
  65     BIO *bio, *b64;
  66     b64 = BIO_new(BIO_f_base64());
  67     bio = BIO_new(BIO_s_mem());
  68     bio = BIO_push(b64, bio);
  69     BIO_set_flags(bio, BIO_FLAGS_BASE64_NO_NL);
  70     int bioWriteRet = BIO_write(bio, src.c_str(), src.length());
  71     if (bioWriteRet < 0 || (size_t) bioWriteRet != src.length()) {
  72       BIO_free_all(bio);
  73       throw std::runtime_error("BIO_write failed to write all data to memory buffer");
  74     }
  75     (void)BIO_flush(bio);
  76     char* pp;
  77     std::string out;
  78     olen = BIO_get_mem_data(bio, &pp);
  79     if (olen > 0) {
  80       out = std::string(pp, olen);
  81     }
  82     BIO_free_all(bio);
  83     return out;
  84   }
  85   return "";
  86 }
  87
  88 #if 0
  89 #include <iostream>
  90 int main() {
  91   std::string in = "PowerDNS Test String 1";
  92   std::string out = Base64Encode(in);
  93   std::cout << out << std::endl;
  94   if (out != "UG93ZXJETlMgVGVzdCBTdHJpbmcgMQ==") {
  95     std::cerr << "output did not match expected data" << std::endl;
  96   }
  97   std::string roundtrip;
  98   B64Decode(out, roundtrip);
  99   std::cout << roundtrip << std::endl;
 100   if (roundtrip != in) {
 101     std::cerr << "roundtripped data did not match input data" << std::endl;
 102   }
 103   return 0;
 104 }
 105 #endif