UNIX BUILD NOTES ==================== Some notes on how to build Bitcoin Core in Unix. (For BSD specific instructions, see `build-*bsd.md` in this directory.) Note --------------------- Always use absolute paths to configure and compile Bitcoin 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. To Build --------------------- ```bash ./autogen.sh ./configure make make install # optional ``` This will build bitcoin-qt as well, if the dependencies are met. Dependencies --------------------- These 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) qt | GUI | GUI toolkit (only needed when GUI enabled) protobuf | Payments in GUI | Data interchange format used for payment protocol (only needed when BIP70 enabled) libqrencode | QR codes in GUI | Optional for generating QR codes (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](dependencies.md) Memory Requirements -------------------- C++ compilers are memory-hungry. It is recommended to have at least 1.5 GB of memory available when compiling Bitcoin 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 ## Linux Distribution Specific Instructions ### Ubuntu & Debian #### Dependency Build Instructions Build requirements: sudo apt-get install build-essential libtool autotools-dev automake pkg-config bsdmainutils python3 Now, you can either build from self-compiled [depends](/depends/README.md) 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 Bitcoin Core without wallet, see [*Disable-wallet mode*](/doc/build-unix.md#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 GUI dependencies: If you want to build bitcoin-qt, make sure that the required packages for Qt development are installed. Qt 5 is necessary to build the GUI. To build without GUI pass `--without-gui`. To build with Qt 5 you need the following: sudo apt-get install libqt5gui5 libqt5core5a libqt5dbus5 qttools5-dev qttools5-dev-tools libqrencode (optional) can be installed with: sudo apt-get install libqrencode-dev protobuf (optional) can be installed with: sudo apt-get install libprotobuf-dev protobuf-compiler Once these are installed, they will be found by configure and a bitcoin-qt executable will be built by default. ### Fedora #### Dependency Build Instructions 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 To build with Qt 5 you need the following: sudo dnf install qt5-qttools-devel qt5-qtbase-devel libqrencode (optional) can be installed with: sudo dnf install qrencode-devel protobuf (optional) can be installed with: sudo dnf install protobuf-devel Notes ----- The release is built with GCC and then "strip bitcoind" to strip the debug symbols, which reduces the executable size by about 90%. miniupnpc --------- [miniupnpc](http://miniupnp.free.fr/) may be used for UPnP port mapping. It can be downloaded from [here]( http://miniupnp.tuxfamily.org/files/). 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 Berkeley DB ----------- 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/](/contrib/install_db4.sh) like so: ```shell ./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*](/doc/build-unix.md#disable-wallet-mode)). Boost ----- If you need to build Boost yourself: sudo su ./bootstrap.sh ./bjam install Security -------- To help make your Bitcoin 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 ./bitcoin The 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, Bitcoin 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 ./bitcoin` The output should contain: STK/REL/PTL RW- R-- RW- The STK RW- means that the stack is readable and writeable but not executable. Disable-wallet mode -------------------- When the intention is to run only a P2P node without a wallet, Bitcoin 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. Additional Configure Flags -------------------------- A list of additional configure flags can be displayed with: ./configure --help Setup and Build Example: Arch Linux ----------------------------------- 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/bitcoin/bitcoin.git cd bitcoin/ ./autogen.sh ./configure --disable-wallet --without-gui --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](https://projects.archlinux.org/svntogit/community.git/tree/bitcoin/trunk/PKGBUILD). As mentioned above, when maintaining portability of the wallet between the standard Bitcoin Core distributions and independently built node software is desired, Berkeley DB 4.8 must be used. ARM Cross-compilation ------------------- 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](../depends/README.md) in the depends directory.