Copyright (c) 2018, The CitiCash Project

Copyright (c) 2018, CitiCash.io

Copyright (c) 2017, Sumokoin.org

Copyright (c) 2014-2017, The Monero Project

Portions Copyright (c) 2012-2013, The Cryptonote developers

Development Resources

• Web: www.citicash.io
• Mail: [email protected]

Introduction

CitiCash is the most secure, private and untraceable decentralised cryptocurrency out there. You are your bank, you control your funds, and nobody can trace your transfers unless you allow them to do so.
CitiCash allows you to create an alias for your address so anyone can send transactions to your alias instead of your address.
CitiCash allows you to attach a text called payment note for the recipient(s) of your transaction.
It's a fork from SUMOKOIN, which is a fork from Monero, a cryptocurrency known for security, privacy, untraceability and active development.
We forked SUMOKOIN, because it seemed to contain higher level of privacy than Monero at the start of the development because of SUMOKOIN using 1) Ring Confidential Transactions (RingCT) from the blockchain start, 2) hard-coded minimum mixin, which we set to 6 and 3) ghost addresses (Monero didn't have them at the time of forking, but now even Monero supports them). These settings significantly reduce the chance of being identified, traced or attacked by blockchain statistical analysis.

CitiCash has a very high privacy setting that is suitable for all high confidential transactions as well as for storage of value without being traced, monitored or identified. We call this true fungibility. This means that each coin is equal and interchangeable; it is highly unlikely that any coin can ever be blacklisted due to previous transactions. Over the course of many years these characteristics will pay off as crypto attacks become more sophisticated with much greater computation power in the future. CitiCash, therefore, is a new CryptoNote implementation with all Monero and SUMOKOIN features without their legacy, so a truly fungible cryptocurrency among just a few ones on the market.

Privacy: CitiCash uses robust cryptographical system to allow you to send and receive funds without your transactions being easily revealed on the blockchain (the ledger of transactions that everyone has). This ensures that your purchases, receipts, and all transfers remain absolutely private by default.
Security: Using the power of a distributed peer-to-peer consensus network, every transaction on the network is cryptographically secured. Individual wallets have a 26 word mnemonic seed that is only displayed once, and can be written down to backup the wallet. Wallet files are encrypted with a passphrase to ensure they are useless if stolen.
Untraceability: By taking advantage of ring signatures, a special property of a certain type of cryptography, CitiCash is able to ensure that transactions are not only untraceable, but have a measure of ambiguity that ensures that transactions cannot easily be tied back to an individual user or computer.

Chronology

Bitcoin protocol => everything public (transaction amount, source and destination)
Zerocoin protocol => some privacy
CryptoNote protocol => added ring signatures so everything private (transaction amount, source and destination)

• Monero (added privacy and fixed security problems that remained in other CryptoNote currencies)
• SUMOKOIN (added ghost addresses before Monero did, RingCT from start, default mixin as minimum mixin)
• Ryo Currency (same as SUMOKOIN, their team splitted)
• CitiCash (added aliases, simple and good-looking wallets, more useful payment-note and other improvements => see below)

Coin Supply & Emission

• Total supply: 1,000,000,000 coins in first 20 years. About 13.5% (~135 million) was premined to reserve for future development, i.e. 865 million coins available for community mining.
• Coin symbol: CCH
• Coin Units:
  • 1 NanoCash  = 0.000000001 CCH (10^-9 - the smallest coin unit)
  • 1 MicroCash = 0.000001 CCH (10^-6)
  • 1 MilliCash = 0.001 CCH (10^-3)
• Hash algorithm: CryptoNight-Heavy (Proof-Of-Work)
• Emission scheme: CitiCash's block reward changes every 6-months as the following "Camel" distribution* (inspired by real-world mining production like of crude oil, coal etc. that is often slow at first, accelerated in the next few years before declined and depleted). However, the emission path of CitiCash is generally not far apart from what of Bitcoin (view charts below).

* The emulated algorithm of Citicash block-reward emission can be found in Python and C++ scripts at scripts directory.

About this Project

This is the core implementation of Citicash. It is open source and completely free to use without restrictions, except for those specified in the license agreement below. There are no restrictions on anyone creating an alternative implementation of Citicash that uses the protocol and network in a compatible manner.

As with many development projects, the repository on Github is considered to be the "staging" area for the latest changes. Before changes are merged into that branch on the main repository, they are tested by individual developers in their own branches, submitted as a pull request, and then subsequently tested by contributors who focus on testing and code reviews. That having been said, the repository should be carefully considered before using it in a production environment, unless there is a patch in the repository for a particular show-stopping issue you are experiencing. It is generally a better idea to use a tagged release for stability.

Anyone is welcome to contribute to Citicash codebase! If you have a fix or code change, feel free to submit is as a pull request directly to the "master" branch. In cases where the change is relatively small or does not affect other parts of the codebase it may be merged in immediately by any one of the collaborators. On the other hand, if the change is particularly large or complex, it is expected that it will be discussed at length either well in advance of the pull request being submitted, or even directly on the pull request.

License

Please view LICENSE

Compiling Citicash from Source

Dependencies

The following table summarizes the tools and libraries required to build. A few of the libraries are also included in this repository (marked as "Vendored"). By default, the build uses the library installed on the system, and ignores the vendored sources. However, if no library is found installed on the system, then the vendored source will be built and used. The vendored sources are also used for statically-linked builds because distribution packages often include only shared library binaries (.so) but not static library archives (.a).

Dep	Min. Version	Vendored	Debian/Ubuntu Pkg	Arch Pkg	Homebrew formulae	Optional	Purpose
GCC	4.7.3	NO	build-essential	base-devel	NA	NO
CMake	3.0.0	NO	cmake	cmake	cmake	NO
pkg-config	any	NO	pkg-config	base-devel	pkg-config	NO
Boost	1.58	NO	libboost-all-dev	boost	boost	NO
OpenSSL	basically any	NO	libssl-dev	openssl	openssl	NO	sha256 sum
BerkeleyDB	4.8	NO	libdb{,++}-dev	db	NA	NO
libevent	2.0	NO	libevent-dev	libevent	NA	NO
libunbound	1.4.16	YES	libunbound-dev	unbound	NA	NO
libminiupnpc	2.0	YES	libminiupnpc-dev	miniupnpc	NA	YES	NAT punching
libunwind	any	NO	libunwind8-dev	libunwind	NA	YES	stack traces
ldns	1.6.17	NO	libldns-dev	ldns	ldns	YES	?
expat	1.1	NO	libexpat1-dev	expat	expat	YES	?
GTest	1.5	YES	libgtest-dev^	gtest	NA	YES	test suite
Doxygen	any	NO	doxygen	doxygen	doxygen	YES	documentation
Graphviz	any	NO	graphviz	graphviz	NA	YES	documentation

[^] On Debian/Ubuntu libgtest-dev only includes sources and headers. You must build the library binary manually. This can be done with the following command sudo apt-get install libgtest-dev && cd /usr/src/gtest && sudo cmake . && sudo make && sudo mv libg* /usr/lib/

Build instructions

Citicash uses the CMake build system and a top-level Makefile that invokes cmake commands as needed.

On Linux and OS X

• Install the dependencies (see the list above)

  - On Ubuntu 18.04 you need to have universe repository added (https://askubuntu.com/questions/148638/how-do-i-enable-the-universe-repository)

    sudo add-apt-repository "deb http://archive.ubuntu.com/ubuntu $(lsb_release -sc) universe"
  

  - And update package list

  sudo apt update

  - On Ubuntu 16.04, essential dependencies can be installed with the following command:

    sudo apt install build-essential cmake libboost-all-dev libssl-dev pkg-config
  

  - On Mac OS X, install Homebrew first.

    ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
  

  Then use it instead of apt or apt-get without sudo.

    brew install cmake pkg-config openssl
  

  If needed install previous version of boost and force it to link.

    brew install [email protected]
    brew link --force [email protected]
  

  Works with clang too.

• Change to the root of the source code directory and build:

    cd citicash
    make
  

  Optional: If your machine has several cores and enough memory, enable parallel build by running make -j<number of threads> instead of make. For this to be worthwhile, the machine should have one core and about 2GB of RAM available per thread.

• The resulting executables can be found in build/release/bin

• Add PATH="$PATH:$HOME/citicash/build/release/bin" to .profile

• Run Citicash with citicashd --detach

• Optional: build and run the test suite to verify the binaries:

    make release-test
  

  NOTE: coretests test may take a few hours to complete.

• Optional: to build binaries suitable for debugging:

     make debug
  

• Optional: to build statically-linked binaries:

     make release-static
  

• Optional: build documentation in doc/html (omit HAVE_DOT=YES if graphviz is not installed):

    HAVE_DOT=YES doxygen Doxyfile
  

On the Raspberry Pi

Tested on a Raspberry Pi 2 with a clean install of minimal Debian Jessie from https://www.raspberrypi.org/downloads/raspbian/

• apt-get update && apt-get upgrade to install all of the latest software

• Install the dependencies for Citicash except libunwind and libboost-all-dev

• Increase the system swap size:

    sudo /etc/init.d/dphys-swapfile stop
    sudo nano /etc/dphys-swapfile
    CONF_SWAPSIZE=1024
    sudo /etc/init.d/dphys-swapfile start

• Install the latest version of boost (this may first require invoking apt-get remove --purge libboost* to remove a previous version if you're not using a clean install):

    cd
    wget https://sourceforge.net/projects/boost/files/boost/1.62.0/boost_1_62_0.tar.bz2
    tar xvfo boost_1_62_0.tar.bz2
    cd boost_1_62_0
    ./bootstrap.sh
    sudo ./b2

• Wait ~8 hours

  sudo ./bjam install

• Wait ~4 hours

• Change to the root of the source code directory and build:

    cd citicash
    make release
  

• Wait ~4 hours

• The resulting executables can be found in build/release/bin

• Add PATH="$PATH:$HOME/citicash/build/release/bin" to .profile

• Run Citicash with citicash --detach

• You may wish to reduce the size of the swap file after the build has finished, and delete the boost directory from your home directory

On Windows:

Binaries for Windows are built on Windows using the MinGW toolchain within MSYS2 environment. The MSYS2 environment emulates a POSIX system. The toolchain runs within the environment and cross-compiles binaries that can run outside of the environment as a regular Windows application.

Preparing the Build Environment

• Download and install the MSYS2 installer, either the 64-bit or the 32-bit package, depending on your system.

• Open the MSYS shell via the MSYS2 Shell shortcut

• Update packages using pacman:

    pacman -Syuu
  

• Exit the MSYS shell using Alt+F4

• Edit the properties for the MSYS2 Shell shortcut changing "msys2_shell.bat" to "msys2_shell.cmd -mingw64" for 64-bit builds or "msys2_shell.cmd -mingw32" for 32-bit builds

• Restart MSYS shell via modified shortcut and update packages again using pacman:

    pacman -Syuu
  

• Install dependencies:

  To build for 64-bit Windows:

    pacman -S mingw-w64-x86_64-toolchain make mingw-w64-x86_64-cmake mingw-w64-x86_64-boost mingw-w64-x86_64-openssl
  

  To build for 32-bit Windows:

    pacman -S mingw-w64-i686-toolchain make mingw-w64-i686-cmake mingw-w64-i686-boost mingw-w64-i686-openssl
  

• Open the MingW shell via MinGW-w64-Win64 Shell shortcut on 64-bit Windows or MinGW-w64-Win64 Shell shortcut on 32-bit Windows. Note that if you are running 64-bit Windows, you will have both 64-bit and 32-bit MinGW shells.

Building

• Make sure path to MSYS2 installed directory in Makefile is correct.

• If you are on a 64-bit system, run:

    make release-static-win64
  

• If you are on a 32-bit system, run:

    make release-static-win32
  

• The resulting executables can be found in build/mingw64/release/bin or build/mingw32/release/bin accordingly.

On FreeBSD:

• Update packages and install the dependencies (on FreeBSD 11.0 x64):

    pkg update; pkg install wget git pkgconf gcc49 cmake db6 icu libevent unbound googletest ldns expat bison boost-libs;
  

• Clone source code, change to the root of the source code directory and build:

    git clone https://github.com/citicashio/citicash; cd citicash; make release-static;
  

On OpenBSD:

This has been tested on OpenBSD 5.8.

You will need to add a few packages to your system. pkg_add db cmake gcc gcc-libs g++ miniupnpc gtest.

The doxygen and graphviz packages are optional and require the xbase set.

The Boost package has a bug that will prevent librpc.a from building correctly. In order to fix this, you will have to Build boost yourself from scratch. Follow the directions here (under "Building Boost"): https://github.com/bitcoin/bitcoin/blob/master/doc/build-openbsd.md

You will have to add the serialization, date_time, and regex modules to Boost when building as they are needed by citicash.

To build: env CC=egcc CXX=eg++ CPP=ecpp DEVELOPER_LOCAL_TOOLS=1 BOOST_ROOT=/path/to/the/boost/you/built make release-static-64

Building Portable Statically Linked Binaries

By default, in either dynamically or statically linked builds, binaries target the specific host processor on which the build happens and are not portable to other processors. Portable binaries can be built using the following targets:

*make release-static-64 builds binaries on Linux on x86_64 portable across POSIX systems on x86_64 processors

• make release-static-32 builds binaries on Linux on x86_64 or i686 portable across POSIX systems on i686 processors
• make release-static-armv8 builds binaries on Linux portable across POSIX systems on armv8 processors
• make release-static-armv7 builds binaries on Linux portable across POSIX systems on armv7 processors
• make release-static-armv6 builds binaries on Linux portable across POSIX systems on armv6 processors
• make release-static-win64 builds binaries on 64-bit Windows portable across 64-bit Windows systems
• make release-static-win32 builds binaries on 64-bit or 32-bit Windows portable across 32-bit Windows systems

Running citicashd

The build places the binary in bin/ sub-directory within the build directory from which cmake was invoked (repository root by default). To run in foreground:

./bin/citicashd

To list all available options, run ./bin/citicashd --help. Options can be specified either on the command line or in a configuration file passed by the --config-file argument. To specify an option in the configuration file, add a line with the syntax argumentname=value, where argumentname is the name of the argument without the leading dashes, for example log-level=1.

To run in background:

./bin/citicashd --log-file citicashd.log --detach

To run as a systemd service, copy citicashd.service to /etc/systemd/system/ and citicashd.conf to /etc/. The example service assumes that the user citicash exists and its home is the data directory specified in the example config.

If you're on Mac, you may need to add the --max-concurrency 1 option to citicash-wallet-cli, and possibly citicashd, if you get crashes refreshing.

Internationalization

Please see README.i18n

Using Tor

While Citicash isn't made to integrate with Tor, it can be used wrapped with torsocks, if you add --p2p-bind-ip 127.0.0.1 to the citicashd command line. You also want to set DNS requests to go over TCP, so they'll be routed through Tor, by setting DNS_PUBLIC=tcp. You may also disable IGD (UPnP port forwarding negotiation), which is pointless with Tor. To allow local connections from the wallet, you might have to add TORSOCKS_ALLOW_INBOUND=1, some OSes need it and some don't. Example:

DNS_PUBLIC=tcp torsocks citicashd --p2p-bind-ip 127.0.0.1 --no-igd

or:

DNS_PUBLIC=tcp TORSOCKS_ALLOW_INBOUND=1 torsocks citicashd --p2p-bind-ip 127.0.0.1 --no-igd

TAILS ships with a very restrictive set of firewall rules. Therefore, you need to add a rule to allow this connection too, in addition to telling torsocks to allow inbound connections. Full example:

sudo iptables -I OUTPUT 2 -p tcp -d 127.0.0.1 -m tcp --dport 18081 -j ACCEPT

DNS_PUBLIC=tcp torsocks ./citicashd --p2p-bind-ip 127.0.0.1 --no-igd --rpc-bind-ip 127.0.0.1 --data-dir /home/your/directory/to/the/blockchain

./citicash-wallet-cli

Using readline

While citicashd and citicash-wallet-cli do not use readline directly, most of the functionality can be obtained by running them via rlwrap. This allows command recall, edit capabilities, etc. It does not give autocompletion without an extra completion file, however. To use rlwrap, simply prepend rlwrap to the command line, eg:

rlwrap bin/citicash-wallet-cli --wallet-file /path/to/wallet

Note: rlwrap will save things like your seed and private keys, if you supply them on prompt. You may want to not use rlwrap when you use simplewallet to restore from seed, etc.

Debugging

This section contains general instructions for debugging failed installs or problems encountered with Citicash. First ensure you are running the latest version built from the github repo.

LMDB

Instructions for debugging suspected blockchain corruption as per @HYC

There is an mdb_stat command in the LMDB source that can print statistics about the database but it's not routinely built. This can be built with the following command:

cd ~/citicash/external/db_drivers/liblmdb && make

The output of mdb_stat -ea <path to blockchain dir> will indicate inconsistencies in the blocks, block_heights and block_info table.

The output of mdb_dump -s blocks <path to blockchain dir> and mdb_dump -s block_info <path to blockchain dir> is useful for indicating whether blocks and block_info contain the same keys.

These records are dumped as hex data, where the first line is the key and the second line is the data.