blob: aa987840b5e7b191c3dc9d7d924f8de273485e4b [file] [log] [blame]
/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -*- */
/*
* Copyright (c) 2013, Regents of the University of California
* Alexander Afanasyev
* Zhenkai Zhu
*
* BSD license, See the LICENSE file for more information
*
* Author: Alexander Afanasyev <alexander.afanasyev@ucla.edu>
* Zhenkai Zhu <zhenkai@cs.ucla.edu>
*/
#include "hash.h"
#include "ndn-cpp/helpers/uri.h"
#include <boost/lexical_cast.hpp>
#include <openssl/evp.h>
#include <fstream>
using namespace boost;
using namespace std;
// Other options: VP_md2, EVP_md5, EVP_sha, EVP_sha1, EVP_sha256, EVP_dss, EVP_dss1, EVP_mdc2, EVP_ripemd160
#define HASH_FUNCTION EVP_sha256
namespace ndn
{
std::ostream &
operator << (std::ostream &os, const Hash &hash)
{
if (hash.m_length == 0)
return os;
ostreambuf_iterator<char> out_it (os); // ostream iterator
// need to encode to base64
copy (detail::string_from_binary (reinterpret_cast<const char*> (hash.m_buf)),
detail::string_from_binary (reinterpret_cast<const char*> (hash.m_buf+hash.m_length)),
out_it);
return os;
}
std::string
Hash::shortHash () const
{
return lexical_cast<string> (*this).substr (0, 10);
}
unsigned char Hash::_origin = 0;
ptr_lib::shared_ptr<Hash> Hash::Origin(new Hash(&Hash::_origin, sizeof(unsigned char)));
ptr_lib::shared_ptr<Hash>
Hash::FromString (const std::string &hashInTextEncoding)
{
ptr_lib::shared_ptr<Hash> retval = make_shared<Hash> (reinterpret_cast<void*> (0), 0);
if (hashInTextEncoding.size () == 0)
{
return retval;
}
if (hashInTextEncoding.size () > EVP_MAX_MD_SIZE * 2)
{
cerr << "Input hash is too long. Returning an empty hash" << endl;
return retval;
}
retval->m_buf = new unsigned char [EVP_MAX_MD_SIZE];
unsigned char *end = copy (detail::string_to_binary (hashInTextEncoding.begin ()),
detail::string_to_binary (hashInTextEncoding.end ()),
retval->m_buf);
retval->m_length = end - retval->m_buf;
return retval;
}
ptr_lib::shared_ptr<Hash>
Hash::FromFileContent (const char *filename)
{
ptr_lib::shared_ptr<Hash> retval = make_shared<Hash> (reinterpret_cast<void*> (0), 0);
retval->m_buf = new unsigned char [EVP_MAX_MD_SIZE];
EVP_MD_CTX *hash_context = EVP_MD_CTX_create ();
EVP_DigestInit_ex (hash_context, HASH_FUNCTION (), 0);
ifstream iff (filename, std::ios::in | std::ios::binary);
while (iff.good ())
{
char buf[1024];
iff.read (buf, 1024);
EVP_DigestUpdate (hash_context, buf, iff.gcount ());
}
retval->m_buf = new unsigned char [EVP_MAX_MD_SIZE];
EVP_DigestFinal_ex (hash_context,
retval->m_buf, &retval->m_length);
EVP_MD_CTX_destroy (hash_context);
return retval;
}
ptr_lib::shared_ptr<Hash>
Hash::FromBytes (const ndn::Bytes &bytes)
{
ptr_lib::shared_ptr<Hash> retval = make_shared<Hash> (reinterpret_cast<void*> (0), 0);
retval->m_buf = new unsigned char [EVP_MAX_MD_SIZE];
EVP_MD_CTX *hash_context = EVP_MD_CTX_create ();
EVP_DigestInit_ex (hash_context, HASH_FUNCTION (), 0);
// not sure whether it's bad to do so if bytes.size is huge
EVP_DigestUpdate(hash_context, ndn::head(bytes), bytes.size());
retval->m_buf = new unsigned char [EVP_MAX_MD_SIZE];
EVP_DigestFinal_ex (hash_context,
retval->m_buf, &retval->m_length);
EVP_MD_CTX_destroy (hash_context);
return retval;
}
} // ndn