NOTE: This section is a work in progress for DeFi Blockchain, and may not be applicable at it's current state.
Some notes on how to build DeFi Core in Unix.
(For BSD specific instructions, see build-*bsd.md in this directory.)
Always use absolute paths to configure and compile DeFi Core and the dependencies. For example, when specifying the path of the dependency:
../dist/configure --enable-cxx --disable-shared --with-pic --prefix=$BDB_PREFIX
Here BDB_PREFIX must be an absolute path - it is defined using $(pwd) which ensures the usage of the absolute path.
./autogen.sh
./configure
make
make install # optionalThese dependencies are required:
| Library | Purpose | Description |
|---|---|---|
| libssl | Crypto | Random Number Generation, Elliptic Curve Cryptography |
| libboost | Utility | Library for threading, data structures, etc |
| libevent | Networking | OS independent asynchronous networking |
Optional dependencies:
| Library | Purpose | Description |
|---|---|---|
| miniupnpc | UPnP Support | Firewall-jumping support |
| libdb4.8 | Berkeley DB | Wallet storage (only needed when wallet enabled) |
| protobuf | Payments in GUI | Data interchange format used for payment protocol (only needed when GUI enabled) |
| univalue | Utility | JSON parsing and encoding (bundled version will be used unless --with-system-univalue passed to configure) |
| libzmq3 | ZMQ notification | Optional, allows generating ZMQ notifications (requires ZMQ version >= 4.0.0) |
For the versions used, see dependencies.md
C++ compilers are memory-hungry. It is recommended to have at least 1.5 GB of memory available when compiling DeFi Core. On systems with less, gcc can be tuned to conserve memory with additional CXXFLAGS:
./configure CXXFLAGS="--param ggc-min-expand=1 --param ggc-min-heapsize=32768"
Alternatively, or in addition, debugging information can be skipped for compilation. The default compile flags are
-g -O2, and can be changed with:
./configure CXXFLAGS="-O2"
Finally, clang (often less resource hungry) can be used instead of gcc, which is used by default:
./configure CXX=clang++ CC=clang
Build requirements:
sudo apt-get install build-essential libtool autotools-dev automake pkg-config bsdmainutils python3 curl
Now, you can either build from self-compiled depends or install the required dependencies:
sudo apt-get install libssl-dev libevent-dev libboost-system-dev libboost-filesystem-dev libboost-chrono-dev libboost-test-dev libboost-thread-dev
BerkeleyDB is required for the wallet.
Ubuntu and Debian have their own libdb-dev and libdb++-dev packages, but these will install
BerkeleyDB 5.1 or later. This will break binary wallet compatibility with the distributed executables, which
are based on BerkeleyDB 4.8. If you do not care about wallet compatibility,
pass --with-incompatible-bdb to configure.
Otherwise, you can build from self-compiled depends (see above).
To build DeFi Core without wallet, see Disable-wallet mode
Optional (see --with-miniupnpc and --enable-upnp-default):
sudo apt-get install libminiupnpc-dev
ZMQ dependencies (provides ZMQ API):
sudo apt-get install libzmq3-dev
Build requirements:
sudo dnf install gcc-c++ libtool make autoconf automake openssl-devel libevent-devel boost-devel libdb4-devel libdb4-cxx-devel python3
Optional (see --with-miniupnpc and --enable-upnp-default):
sudo dnf install miniupnpc-devel
ZMQ dependencies (provides ZMQ API):
sudo dnf install zeromq-devel
The release is built with GCC and then "strip defid" to strip the debug symbols, which reduces the executable size by about 90%.
miniupnpc may be used for UPnP port mapping. It can be downloaded from here. UPnP support is compiled in and turned off by default. See the configure options for upnp behavior desired:
--without-miniupnpc No UPnP support miniupnp not required
--disable-upnp-default (the default) UPnP support turned off by default at runtime
--enable-upnp-default UPnP support turned on by default at runtime
It is recommended to use Berkeley DB 4.8. If you have to build it yourself, you can use the installation script included in contrib/ like so:
./contrib/install_db4.sh `pwd`from the root of the repository.
Note: You only need Berkeley DB if the wallet is enabled (see Disable-wallet mode).
If you need to build Boost yourself:
sudo su
./bootstrap.sh
./bjam install
To help make your DeFi Core installation more secure by making certain attacks impossible to exploit even if a vulnerability is found, binaries are hardened by default. This can be disabled with:
Hardening Flags:
./configure --enable-hardening
./configure --disable-hardening
Hardening enables the following features:
-
Position Independent Executable: Build position independent code to take advantage of Address Space Layout Randomization offered by some kernels. Attackers who can cause execution of code at an arbitrary memory location are thwarted if they don't know where anything useful is located. The stack and heap are randomly located by default, but this allows the code section to be randomly located as well.
On an AMD64 processor where a library was not compiled with -fPIC, this will cause an error such as: "relocation R_X86_64_32 against `......' can not be used when making a shared object;"
To test that you have built PIE executable, install scanelf, part of paxutils, and use:
scanelf -e ./defiThe output should contain:
TYPE ET_DYN
-
Non-executable Stack: If the stack is executable then trivial stack-based buffer overflow exploits are possible if vulnerable buffers are found. By default, DeFi Core should be built with a non-executable stack, but if one of the libraries it uses asks for an executable stack or someone makes a mistake and uses a compiler extension which requires an executable stack, it will silently build an executable without the non-executable stack protection.
To verify that the stack is non-executable after compiling use:
scanelf -e ./defiThe output should contain: STK/REL/PTL RW- R-- RW-
The STK RW- means that the stack is readable and writeable but not executable.
When the intention is to run only a P2P node without a wallet, DeFi Core may be compiled in disable-wallet mode with:
./configure --disable-wallet
In this case there is no dependency on Berkeley DB 4.8.
Mining is also possible in disable-wallet mode using the getblocktemplate RPC call.
A list of additional configure flags can be displayed with:
./configure --help
This example lists the steps necessary to setup and build a command line only, non-wallet distribution of the latest changes on Arch Linux:
pacman -S git base-devel boost libevent python
git clone https://github.com/defich/ain.git
cd ain/
./autogen.sh
./configure --disable-wallet --without-miniupnpc
make check
Note:
Enabling wallet support requires either compiling against a Berkeley DB newer than 4.8 (package db) using --with-incompatible-bdb,
or building and depending on a local version of Berkeley DB 4.8. The readily available Arch Linux packages are currently built using
--with-incompatible-bdb according to the PKGBUILD.
As mentioned above, when maintaining portability of the wallet between the standard DeFi Core distributions and independently built
node software is desired, Berkeley DB 4.8 must be used.
These steps can be performed on, for example, an Ubuntu VM. The depends system will also work on other Linux distributions, however the commands for installing the toolchain will be different.
Make sure you install the build requirements mentioned above. Then, install the toolchain and curl:
sudo apt-get install g++-arm-linux-gnueabihf curl
To build executables for ARM:
cd depends
make HOST=arm-linux-gnueabihf NO_QT=1
cd ..
./autogen.sh
./configure --prefix=$PWD/depends/arm-linux-gnueabihf --enable-glibc-back-compat --enable-reduce-exports LDFLAGS=-static-libstdc++
make
For further documentation on the depends system see README.md in the depends directory.