ld: symbol(s) not found with OpenSSL (libssl)

Question

I'm trying to build TorTunnel on my mac. I've successfully installed the Boost library and its development files. TorTunnel also requires the OpenSSL and its development files.

I've got them installed in /usr/lib/libssl.dylib and /usr/include/openssl/.

When I run the make command this is the error i'm getting:

g++ -ggdb -g -O2 -lssl -lboost_system-xgcc42-mt-1_38  -o torproxy TorProxy.o HybridEncryption.o Connection.o Cell.o Directory.o ServerListing.o Util.o Circuit.o CellEncrypter.o RelayCellDispatcher.o CellConsumer.o ProxyShuffler.o CreateCell.o CreatedCell.o TorTunnel.o SocksConnection.o Network.o  
Undefined symbols:
  "_BN_hex2bn", referenced from:
      Circuit::initializeDhParameters()      in Circuit.o
  "_BN_free", referenced from:
      Circuit::~Circuit()in Circuit.o
      Circuit::~Circuit()in Circuit.o
      CreatedCell::getKeyMaterial(unsigned char**, unsigned char**)in CreatedCell.o
  "_DH_generate_key", referenced from:
      Circuit::initializeDhParameters()      in Circuit.o
  "_PEM_read_bio_RSAPublicKey", referenced from:
      ServerListing::getOnionKey()       in ServerListing.o
  "_BIO_s_mem", referenced from:
      Connection::initializeSSL()       in Connection.o
      Connection::initializeSSL()       in Connection.o
  "_DH_free", referenced from:
      Circuit::~Circuit()in Circuit.o
  "_BIO_ctrl_pending", referenced from:
      Connection::writeFromBuffer(boost::function)in Connection.o
  "_RSA_size", referenced from:
      HybridEncryption::encryptInSingleChunk(unsigned char*, int, unsigned char**, int*, rsa_st*)in HybridEncryption.o
      HybridEncryption::encryptInHybridChunk(unsigned char*, int, unsigned char**, int*, rsa_st*)in HybridEncryption.o
      HybridEncryption::encrypt(unsigned char*, int, unsigned char**, int*, rsa_st*)in HybridEncryption.o
  "_RSA_public_encrypt", referenced from:
      HybridEncryption::encryptInSingleChunk(unsigned char*, int, unsigned char**, int*, rsa_st*)in HybridEncryption.o
      HybridEncryption::encryptInHybridChunk(unsigned char*, int, unsigned char**, int*, rsa_st*)in HybridEncryption.o
  "_BN_num_bits", referenced from:
      CreateCell::CreateCell(unsigned short, dh_st*, rsa_st*)in CreateCell.o
      CreatedCell::getKeyMaterial(unsigned char**, unsigned char**)in CreatedCell.o
      CreatedCell::getKeyMaterial(unsigned char**, unsigned char**)in CreatedCell.o
      CreatedCell::isValid()      in CreatedCell.o
  "_SHA1", referenced from:
      CellEncrypter::expandKeyMaterial(unsigned char*, int, unsigned char*, int)in CellEncrypter.o
  "_BN_bn2bin", referenced from:
      CreateCell::CreateCell(unsigned short, dh_st*, rsa_st*)in CreateCell.o
  "_BN_bin2bn", referenced from:
      CreatedCell::getKeyMaterial(unsigned char**, unsigned char**)in CreatedCell.o
  "_DH_compute_key", referenced from:
      CreatedCell::getKeyMaterial(unsigned char**, unsigned char**)in CreatedCell.o
  "_BIO_new", referenced from:
      Connection::initializeSSL()       in Connection.o
      Connection::initializeSSL()       in Connection.o
  "_BIO_new_mem_buf", referenced from:
      ServerListing::getOnionKey()       in ServerListing.o
  "_AES_ctr128_encrypt", referenced from:
      HybridEncryption::AES_encrypt(unsigned char*, int, unsigned char*, unsigned char*, int)in HybridEncryption.o
      CellEncrypter::aesOperate(Cell&, aes_key_st*, unsigned char*, unsigned char*, unsigned int*)in CellEncrypter.o
  "_BIO_read", referenced from:
      Connection::writeFromBuffer(boost::function)in Connection.o
  "_SHA1_Update", referenced from:
      CellEncrypter::calculateDigest(SHAstate_st*, RelayCell&, unsigned char*)in CellEncrypter.o
      CellEncrypter::initKeyMaterial(unsigned char*)in CellEncrypter.o
      CellEncrypter::initKeyMaterial(unsigned char*)in CellEncrypter.o
  "_SHA1_Final", referenced from:
      CellEncrypter::calculateDigest(SHAstate_st*, RelayCell&, unsigned char*)in CellEncrypter.o
  "_DH_size", referenced from:
      CreatedCell::getKeyMaterial(unsigned char**, unsigned char**)in CreatedCell.o
  "_DH_new", referenced from:
      Circuit::initializeDhParameters()      in Circuit.o
  "_BIO_write", referenced from:
      Connection::readIntoBufferComplete(boost::function, boost::system::error_code const&, unsigned long)in Connection.o
  "_RSA_free", referenced from:
      Circuit::~Circuit()in Circuit.o
  "_BN_dup", referenced from:
      Circuit::initializeDhParameters()      in Circuit.o
      Circuit::initializeDhParameters()      in Circuit.o
  "_BN_new", referenced from:
      Circuit::initializeDhParameters()      in Circuit.o
      Circuit::initializeDhParameters()      in Circuit.o
  "_SHA1_Init", referenced from:
      CellEncrypter::CellEncrypter()in CellEncrypter.o
      CellEncrypter::CellEncrypter()in CellEncrypter.o
  "_RAND_bytes", referenced from:
      HybridEncryption::encryptInHybridChunk(unsigned char*, int, unsigned char**, int*, rsa_st*)in HybridEncryption.o
      Util::getRandomId()      in Util.o
  "_AES_set_encrypt_key", referenced from:
      HybridEncryption::AES_encrypt(unsigned char*, int, unsigned char*, unsigned char*, int)in HybridEncryption.o
      CellEncrypter::initKeyMaterial(unsigned char*)in CellEncrypter.o
      CellEncrypter::initKeyMaterial(unsigned char*)in CellEncrypter.o
  "_BN_set_word", referenced from:
      Circuit::initializeDhParameters()      in Circuit.o
  "_RSA_new", referenced from:
      ServerListing::getOnionKey()       in ServerListing.o
ld: symbol(s) not found
collect2: ld returned 1 exit status
make: *** [torproxy] Error 1

Any idea how I could fix it?

Answer 1

If libcrypto is already installed in /opt/local/lib, change -lcrypt flag to -lcrypto flag.

 g++ -ggdb -g -O2 -L/opt/local/lib -L/usr/lib -lssl -lcrypto -lboost_system-mt

Answer 2

At least on of the missing symbols is not part of libssl but part of libcrypto:

diciu:~ diciu$ nm /usr/lib/libcrypto.dylib | grep PEM_read_bio_RSAPublicKey
00031d20 T _PEM_read_bio_RSAPublicKey

Add "-lcrypto" to your compile line.

Answer 3

You also need libcrypto.

Change your link line to:

g++ -ggdb -g -O2 -lssl -lcrypt ... as before ...