- Check out our [Vulnerability Response Process](https://github.com/loki-project/Meta/blob/master/VULNERABILITY_RESPONSE_LOKI.md), encourages prompt disclosure of any Vulnerabilities
Loki is a private cryptocurrency based on Monero. Over the course of the coming months, the Loki project aims to offer an incenvised full node layer with a secondary p2p network that offers a private communications layer based on the Tox protocol.
More information on the project can be found on the website and in the whitepaper.
Loki is an open source project, and we encourage contributions from anyone with something to offer. For more information on contributing, please contact team@loki.network
## Compiling Loki 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 | Optional | Purpose |
| expat | 1.1 | NO | `libexpat1-dev` | `expat` | YES | XML parsing |
| GTest | 1.5 | YES | `libgtest-dev`^ | `gtest` | YES | Test suite |
| Doxygen | any | NO | `doxygen` | `doxygen` | YES | Documentation |
| Graphviz | any | NO | `graphviz` | `graphviz` | 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/ ```
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](#note-for-raspbian-jessie-users).
*`apt-get update && apt-get upgrade` to install all of the latest software
* Install the dependencies for Loki 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=1024
sudo /etc/init.d/dphys-swapfile start
```
* Clone loki and checkout most recent release version:
* The resulting executables can be found in `build/release/bin`
* Add `PATH="$PATH:$HOME/loki/build/release/bin"` to `.profile`
* Run Loki with `lokid --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 Loki is a bit more complicated. The version of Boost available in the Debian Jessie repositories is too old to use with Loki, 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=1024
sudo /etc/init.d/dphys-swapfile start
```
* Then, install the dependencies for Loki 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):
* From here, follow the [general Raspberry Pi instructions](#on-the-raspberry-pi) from the "Clone loki and checkout most recent release version" step.
#### On Windows:
Binaries for Windows are built on Windows using the MinGW toolchain within
[MSYS2 environment](http://msys2.github.io). 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](http://msys2.github.io), 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 mingw-w64-x86_64-zeromq mingw-w64-x86_64-libsodium
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
* 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**
* 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`
The project can be built from scratch by following instructions for Linux above. If you are running loki in a jail you need to add the flag: `allow.sysvipc=1` to your jail configuration, otherwise lmdb will throw the error message: `Failed to open lmdb environment: Function not implemented`.
### On OpenBSD:
#### OpenBSD < 6.2
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"):
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
## Running lokid
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/lokid
To list all available options, run `./bin/lokid --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/lokid --log-file lokid.log --detach
## Internationalization
See [README.i18n.md](README.i18n.md).
## Using Tor
While Loki 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
lokid.conf to disable listening for connections on external interfaces.
*`--no-igd` on the command line or `no-igd=1` in lokid.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, lokid uses the default list of
servers defined in [src/common/dns_utils.cpp](src/common/dns_utils.cpp).
*`TORSOCKS_ALLOW_INBOUND=1` to tell torsocks to allow lokid 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/lokid.service](utils/systemd/lokid.service) for details).
This section contains general instructions for debugging failed installs or problems encountered with Loki. 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/lokid `pidof lokid`
```
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 lokid. 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/lokid /path/to/dumpfile`
Print the stack trace with `bt`
* To run loki within gdb:
Type `gdb /path/to/lokid`
Pass command-line options with `--args` followed by the relevant arguments
Type `run` to run lokid
### Analysing memory corruption
We use the tool `valgrind` for this.
Run with `valgrind /path/to/lokid`. It will be 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 ~/loki/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.