sumokoin

Sumokoin

Copyright © 2017-2021, Sumokoin Projects

Portions Copyright © 2014-2021, The Monero Project

Portions Copyright © 2012-2013, The Cryptonote developers

Table of Contents

• Development resources
• Coverage
• Introduction
• Coin Supply & Emission
• About this project
• License
• Compiling Sumokoin from source
  • Dependencies
• Using Tor
• Pruning
• Debugging
• Known issues

Development Resources

• Web: www.sumokoin.org
• Mail: [email protected]

Please note that code is developed on the dev branch, if you want to check out the latest updates, before they are merged on main branch, please refer there. Master branch will always point to a version that we consider stable, so you can download the code by simply typing git clone https://github.com/sumoprojects/sumokoin.git

Coverage

Type	Status
Workflows

Introduction

Sumokoin (スモコイン in Japanese) is a fork from Monero, one of the most respectable cryptocurrency well-known for security, privacy, untraceability and active development. Starting as an educational project, we found that it would be great to create a new coin with high level of privacy by (1) moving forward right away to Ring Confidential Transactions (RingCT), (2) setting minimum transaction mixin to 12 (current minimum mixin set at 48) that would greatly reduce chance of being attacked, traced or identified by (blockchain) statistical analysis.

Sumokoin, therefore, is a new Monero without its legacy, a truely fungible cryptocurrency among just a few ones in the market.

Coin Supply & Emission

• Total supply: 88,888,888 coins in first 20 years, then 263,000 coins each year for inflation. About 10% (~8.8 million) was premined to reserve for future development, i.e. 80 million coins available for community mining.
• Coin symbol: SUMO
• Coin Units:
  • 1 Sumoshi  = 0.000000001 SUMO (10^-9 - the smallest coin unit)
  • 1 Sumokun = 0.000001 SUMO (10^-6)
  • 1 Sumosan = 0.001 SUMO (10^-3)
• Hash algorithm: CryptoNight R (cnR, CNv4) (Proof-Of-Work)
• Emission scheme: Sumokoin’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 Sumokoin is generally not far apart from what of Bitcoin (view charts below).

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

About this Project

This is the core implementation of Sumokoin. 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 Sumokoin 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 Sumokoin’s 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 Sumokoin 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	Fedora	Optional	Purpose
GCC	5.4.0	NO	build-essential	base-devel	gcc	NO
CMake	3.5	NO	cmake	cmake	cmake	NO
pkg-config	any	NO	pkg-config	base-devel	pkgconf	NO
Boost	1.58	NO	libboost-all-dev	boost	boost-devel	NO	C++ libraries
OpenSSL	basically any	NO	libssl-dev	openssl	openssl-devel	NO	sha256 sum
libzmq	4.2.0	NO	libzmq3-dev	zeromq	zeromq-devel	NO	ZeroMQ library
OpenPGM	?	NO	libpgm-dev	libpgm	openpgm-devel	NO	For ZeroMQ
libnorm[2]	?	NO	libnorm-dev			YES	For ZeroMQ
libunbound	1.4.16	YES	libunbound-dev	unbound	unbound-devel	NO	DNS resolver
libevent	?	NO	libevent-dev	libevent	libevent-devel	YES	For unbound
libsodium	?	NO	libsodium-dev	libsodium	libsodium-devel	NO	cryptography
libunwind	any	NO	libunwind8-dev	libunwind	libunwind-devel	YES	Stack traces
liblzma	any	NO	liblzma-dev	xz	xz-devel	YES	For libunwind
libreadline	6.3.0	NO	libreadline6-dev	readline	readline-devel	YES	Input editing
ldns	1.6.17	NO	libldns-dev	ldns	ldns-devel	YES	SSL toolkit
expat	1.1	NO	libexpat1-dev	expat	expat-devel	YES	XML parsing
GTest	1.5	YES	libgtest-dev[1]	gtest	gtest-devel	YES	Test suite
Doxygen	any	NO	doxygen	doxygen	doxygen	YES	Documentation
Graphviz	any	NO	graphviz	graphviz	graphviz	YES	Documentation
libhidapi	?	NO	libhidapi-dev	hidapi	hidapi-devel	YES	Hardware wallet
libusb	?	NO	libusb-1.0-0-dev	libusb	libusbx-devel	YES	Hardware wallet
protoc	?	NO	protobuf-compiler	protobuf	protobuf-compiler	YES	Hardware wallet
libudev	?	No	libudev-dev	systemd	systemd-devel	YES	Hardware wallet

[1] 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/ [2] libnorm-dev is needed if your zmq library was built with libnorm, and not needed otherwise

Install all dependencies at once on Debian/Ubuntu:

sudo apt update && sudo apt install build-essential cmake pkg-config libssl-dev libzmq3-dev libunbound-dev libsodium-dev libunwind8-dev liblzma-dev libreadline6-dev libldns-dev libexpat1-dev libpgm-dev qttools5-dev-tools libhidapi-dev libusb-1.0-0-dev libudev-dev libboost-chrono-dev libboost-date-time-dev libboost-filesystem-dev libboost-locale-dev libboost-program-options-dev libboost-regex-dev libboost-serialization-dev libboost-system-dev libboost-thread-dev ccache doxygen graphviz

Install all dependencies at once on macOS with the provided Brewfile: brew update && brew bundle --file=contrib/brew/Brewfile

FreeBSD one liner for required to build dependencies pkg install git gmake cmake pkgconf boost-libs libzmq4 libsodium

Cloning the repository

$ git clone https://github.com/sumoprojects/sumokoin

Build instructions

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

On Linux and macOS

• Install the dependencies (see the list above)

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

    sudo apt update && sudo apt install build-essential cmake pkg-config libboost-all-dev libssl-dev libzmq3-dev libunbound-dev libsodium-dev libunwind8-dev liblzma-dev libreadline6-dev libldns-dev libexpat1-dev doxygen graphviz libpgm-dev libhidapi-dev libusb-dev
  

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

  cd sumokoin
  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.

  Note: The instructions above will compile the most stable release of the Sumokoin software. If you would like to use and test the most recent software, use git checkout master. The master branch may contain updates that are both unstable and incompatible with release software, though testing is always encouraged.

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

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

• Run Sumokoin with sumokoind --detach

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

  make release-test
  

  NOTE: core_tests 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
  

Dependencies need to be built with -fPIC. Static libraries usually aren’t, so you may have to build them yourself with -fPIC. Refer to their documentation for how to build them.

• 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 Zero with a clean install of minimal Raspbian Stretch (2017-09-07 or later) from https://www.raspberrypi.org/downloads/raspbian/. If you are using Raspian Jessie, please see note in the following section.

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

• Install the dependencies for Sumokoin from the ‘Debian’ column in the table above.

• Increase the system swap size:

  sudo /etc/init.d/dphys-swapfile stop
  sudo nano /etc/dphys-swapfile
  CONF_SWAPSIZE=2048
  sudo /etc/init.d/dphys-swapfile start
  

• If using an external hard disk without an external power supply, ensure it gets enough power to avoid hardware issues when syncing, by adding the line “max_usb_current=1” to /boot/config.txt

• Clone sumokoin and checkout most recent release version:

  git clone https://github.com/sumoprojects/sumokoin.git
  cd sumokoin
  git checkout tags/v0.8.0.0
  

• Build:

  make release
  

• Wait 4-6 hours

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

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

• Run Sumokoin with sumokoind --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

Note for Raspbian Jessie users:

If you are using the older Raspbian Jessie image, compiling Sumokoin is a bit more complicated. The version of Boost available in the Debian Jessie repositories is too old to use with Sumokoin, and thus you must compile a newer version yourself. The following explains the extra steps, and has been tested on a Raspberry Pi 2 with a clean install of minimal Raspbian Jessie.

• As before, apt-get update && apt-get upgrade to install all of the latest software, and increase the system swap size

  sudo /etc/init.d/dphys-swapfile stop
  sudo nano /etc/dphys-swapfile
  CONF_SWAPSIZE=2048
  sudo /etc/init.d/dphys-swapfile start
  

• Then, install the dependencies for Sumokoin except libunwind and libboost-all-dev

• 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/1.64.0/boost_1_64_0.tar.bz2
  tar xvfo boost_1_64_0.tar.bz2
  cd boost_1_64_0
  ./bootstrap.sh
  sudo ./b2
  

• Wait ~8 hours

  sudo ./bjam cxxflags=-fPIC cflags=-fPIC -a install
  

• Wait ~4 hours

• From here, follow the general Raspberry Pi instructions from the “Clone sumokoin and checkout most recent release version” step.

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 -Syu
  

• 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 -Syu
  

• 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 mingw-w64-x86_64-zeromq mingw-w64-x86_64-libsodium mingw-w64-x86_64-hidapi mingw-w64-x86_64-unbound
  

  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 mingw-w64-i686-zeromq mingw-w64-i686-libsodium mingw-w64-i686-hidapi mingw-w64-i686-unbound
  

• 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.

Cloning

• To git clone, run:

  git clone https://github.com/sumoprojects/sumokoin.git
  

Building

• Change to the cloned directory, run:

  cd sumokoin
  

• If you would like a specific version/tag, do a git checkout for that version. eg. ‘v0.8.0.0’. If you don’t care about the version and just want binaries from master, skip this step:

  git checkout v0.8.0.0
  

• 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/release/bin

• Optional: to build Windows binaries suitable for debugging on a 64-bit system, run:

  make debug-static-win64
  

• Optional: to build Windows binaries suitable for debugging on a 32-bit system, run:

  make debug-static-win32
  

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

On FreeBSD:

The project can be built from scratch by following instructions for Linux above(but use gmake instead of make). If you are running Sumokoin in a jail, you need to add sysvsem="new" to your jail configuration, otherwise lmdb will throw the error message: Failed to open lmdb environment: Function not implemented.

On OpenBSD:

You will need to add a few packages to your system. pkg_add cmake gmake zeromq libiconv boost.

The doxygen and graphviz packages are optional and require the xbase set. Running the test suite also requires py-requests package.

Build sumokoin: env DEVELOPER_LOCAL_TOOLS=1 BOOST_ROOT=/usr/local gmake release-static

Note: you may encounter the following error, when compiling the latest version of sumokoin as a normal user:

LLVM ERROR: out of memory
c++: error: unable to execute command: Abort trap (core dumped)

Then you need to increase the data ulimit size to 2GB and try again: ulimit -d 2000000

On NetBSD:

Check that the dependencies are present: pkg_info -c libexecinfo boost-headers boost-libs protobuf readline libusb1 zeromq git-base pkgconf gmake cmake | more, and install any that are reported missing, using pkg_add or from your pkgsrc tree. Readline is optional but worth having.

Third-party dependencies are usually under /usr/pkg/, but if you have a custom setup, adjust the “/usr/pkg” (below) accordingly.

Clone the sumokoin repository and checkout the most recent release as described above. Then build sumokoin: gmake BOOST_ROOT=/usr/pkg LDFLAGS="-Wl,-R/usr/pkg/lib" release. The resulting executables can be found in build/NetBSD/[Release version]/Release/bin/.

On Solaris:

The default Solaris linker can’t be used, you have to install GNU ld, then run cmake manually with the path to your copy of GNU ld:

mkdir -p build/release
cd build/release
cmake -DCMAKE_LINKER=/path/to/ld -D CMAKE_BUILD_TYPE=Release ../..
cd ../..

Then you can run make as usual.

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-linux-x86_64 builds binaries on Linux on x86_64 portable across POSIX systems on x86_64 processors
• make release-static-linux-i686 builds binaries on Linux on x86_64 or i686 portable across POSIX systems on i686 processors
• make release-static-linux-armv8 builds binaries on Linux portable across POSIX systems on armv8 processors
• make release-static-linux-armv7 builds binaries on Linux portable across POSIX systems on armv7 processors
• make release-static-linux-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

Cross Compiling

You can also cross-compile static binaries on Linux for Windows and macOS with the depends system. Read more at contrib/depends/README.md

• make depends target=x86_64-linux-gnu for 64-bit linux binaries.
• make depends target=x86_64-w64-mingw32 for 64-bit windows binaries.
  • Requires: python3 g++-mingw-w64-x86-64 wine1.6 bc
• make depends target=x86_64-apple-darwin14 for macOS binaries.
  • Requires: cmake imagemagick libcap-dev librsvg2-bin libz-dev libbz2-dev libtiff-tools python-dev python-pip, and pip install setuptools
• make depends target=i686-linux-gnu for 32-bit linux binaries.
  • Requires: g++-multilib bc
• make depends target=i686-w64-mingw32 for 32-bit windows binaries.
  • Requires: python3 g++-mingw-w64-i686
• make depends target=arm-linux-gnueabihf for armv7 binaries.
  • Requires: g++-arm-linux-gnueabihf
• make depends target=aarch64-linux-gnu for armv8 binaries.
  • Requires: g++-aarch64-linux-gnu
• make depends target=riscv64-linux-gnu for RISC V 64 bit binaries.
  • Requires: g++-riscv64-linux-gnu
• make depends target=x86_64-unknown-freebsd for FreeBSD 64-bit binaries.
  • Requires: clang-8
• make depends target=arm-linux-android for 32bit android binaries
• make depends target=aarch64-linux-android for 64bit android binaries

The required packages are the names for each toolchain on apt. Depending on your distro, they may have different names.

Using depends might also be easier to compile Sumokoin on Windows than using MSYS. Activate Windows Subsystem for Linux (WSL) with a distro (for example Ubuntu), install the apt build-essentials and follow the depends steps as depicted above.

The produced binaries still link libc dynamically. If the binary is compiled on a current distribution, it might not run on an older distribution with an older installation of libc. Passing -DBACKCOMPAT=ON to cmake will make sure that the binary will run on systems having at least libc version 2.17.

Running sumokoind

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/sumokoind

To list all available options, run ./bin/sumokoind --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/sumokoind --log-file sumokoind.log --detach

To run as a systemd service, copy sumokoind.service to /etc/systemd/system/ and sumokoind.conf to /etc/. The example service assumes that the user sumokoin 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 sumo-wallet-cli, and possibly sumokoind, if you get crashes refreshing.

Using Tor

There is a new, still experimental, integration with Tor. The feature allows connecting over IPv4 and Tor simulatenously - IPv4 is used for relaying blocks and relaying transactions received by peers whereas Tor is used solely for relaying transactions received over local RPC. This provides privacy and better protection against surrounding node (sybil) attacks.

While Sumokoin isn’t made to integrate with Tor, it can be used wrapped with torsocks, by setting the following configuration parameters and environment variables:

• --p2p-bind-ip 127.0.0.1 on the command line or p2p-bind-ip=127.0.0.1 in sumokoind.conf to disable listening for connections on external interfaces.
• --no-igd on the command line or no-igd=1 in sumokoind.conf to disable IGD (UPnP port forwarding negotiation), which is pointless with Tor.
• DNS_PUBLIC=tcp or DNS_PUBLIC=tcp://x.x.x.x where x.x.x.x is the IP of the desired DNS server, for DNS requests to go over TCP, so that they are routed through Tor. When IP is not specified, sumokoind uses the default list of servers defined in src/common/dns_utils.cpp.
• TORSOCKS_ALLOW_INBOUND=1 to tell torsocks to allow sumokoind to bind to interfaces to accept connections from the wallet. On some Linux systems, torsocks allows binding to localhost by default, so setting this variable is only necessary to allow binding to local LAN/VPN interfaces to allow wallets to connect from remote hosts. On other systems, it may be needed for local wallets as well.
• Do NOT pass --detach when running through torsocks with systemd, (see utils/systemd/sumokoind.service for details).
• If you use the wallet with a Tor daemon via the loopback IP (eg, 127.0.0.1:9050), then use --untrusted-daemon unless it is your own hidden service.

Example command line to start sumokoind through Tor:

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

Using Tor on Tails

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 19734 -j ACCEPT
    DNS_PUBLIC=tcp torsocks ./sumokoind --p2p-bind-ip 127.0.0.1 --no-igd --rpc-bind-ip 127.0.0.1 \
        --data-dir /home/amnesia/Persistent/your/directory/to/the/blockchain

Pruning

As of June 2021, The full Sumokoin blockchain file is on about 22 GB. One can store a pruned blockchain, which is less than one fourth in size from the full blockchain size (June 2020 4.6 GB). A pruned blockchain can only serve part of the historical chain data to other peers, but is otherwise identical in functionality to the full blockchain. To use a pruned blockchain, it is best to start the initial sync with --pruned-blockchain. However, it is also possible to prune an existing blockchain using the sumo-blockchain-prune tool or using the --pruned-blockchain sumokoind option with an existing chain. If an existing chain exists, pruning will temporarily require disk space to store both the full and pruned blockchains.

Debugging

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

Obtaining stack traces and core dumps on Unix systems

We generally use the tool gdb (GNU debugger) to provide stack trace functionality, and ulimit to provide core dumps in builds which crash or segfault.

• To use gdb in order to obtain a stack trace for a build that has stalled:

Run the build.

Once it stalls, enter the following command:

gdb /path/to/sumokoind `pidof sumokoind`

Type thread apply all bt within gdb in order to obtain the stack trace

• If however the core dumps or segfaults:

Enter ulimit -c unlimited on the command line to enable unlimited filesizes for core dumps

Enter echo core | sudo tee /proc/sys/kernel/core_pattern to stop cores from being hijacked by other tools

Run the build.

When it terminates with an output along the lines of “Segmentation fault (core dumped)”, there should be a core dump file in the same directory as sumokoind. It may be named just core, or core.xxxx with numbers appended.

You can now analyse this core dump with gdb as follows:

gdb /path/to/sumokoind /path/to/dumpfile

Print the stack trace with bt

• If a program crashed and cores are managed by systemd, the following can also get a stack trace for that crash:

coredumpctl -1 gdb

To run sumokoin within gdb:

Type gdb /path/to/sumokoind

Pass command-line options with --args followed by the relevant arguments

Type run to run sumokoind

Analysing memory corruption

There are two tools available:

ASAN

Configure Sumokoin with the -D SANITIZE=ON cmake flag, eg:

cd build/debug && cmake -D SANITIZE=ON -D CMAKE_BUILD_TYPE=Debug ../..

You can then run the Sumokoin tools normally. Performance will typically halve.

valgrind

Install valgrind and run as valgrind /path/to/sumokoind. It will be very slow.

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 ~/sumokoin/src/lmdb/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.

Known Issues

Protocols

Socket-based

Because of the nature of the socket-based protocols that drive sumokoin, certain protocol weaknesses are somewhat unavoidable at this time. While these weaknesses can theoretically be fully mitigated, the effort required (the means) may not justify the ends. As such, please consider taking the following precautions if you are a sumokoin node operator:

• Run sumokoind on a “secured” machine. If operational security is not your forte, at a very minimum, have a dedicated a computer running sumokoind and do not browse the web, use email clients, or use any other potentially harmful apps on your sumokoind machine. Do not click links or load URL/MUA content on the same machine. Doing so may potentially exploit weaknesses in commands which accept “localhost” and “127.0.0.1”.
• If you plan on hosting a public “remote” node, start sumokoind with --restricted-rpc. This is a must.

Blockchain-based

Certain blockchain “features” can be considered “bugs” if misused correctly. Consequently, please consider the following:

• When receiving sumokoin, be aware that it may be locked for an arbitrary time if the sender elected to, preventing you from spending that sumokoin until the lock time expires. You may want to hold off acting upon such a transaction until the unlock time lapses. To get a sense of that time, you can consider the remaining blocktime until unlock as seen in the show_transfers command.