Mercurial > dropbear
view libtommath/README.md @ 1790:42745af83b7d
Introduce extra delay before closing unauthenticated sessions
To make it harder for attackers, introduce a delay to keep an
unauthenticated session open a bit longer, thus blocking a connection
slot until after the delay.
Without this, while there is a limit on the amount of attempts an attacker
can make at the same time (MAX_UNAUTH_PER_IP), the time taken by dropbear to
handle one attempt is still short and thus for each of the allowed parallel
attempts many attempts can be chained one after the other. The attempt rate
is then:
"MAX_UNAUTH_PER_IP / <process time of one attempt>".
With the delay, this rate becomes:
"MAX_UNAUTH_PER_IP / UNAUTH_CLOSE_DELAY".
| author | Thomas De Schampheleire <thomas.de_schampheleire@nokia.com> |
|---|---|
| date | Wed, 15 Feb 2017 13:53:04 +0100 |
| parents | 1051e4eea25a |
| children |
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# libtommath This is the git repository for [LibTomMath](http://www.libtom.net/LibTomMath/), a free open source portable number theoretic multiple-precision integer (MPI) library written entirely in C. ## Build Status ### Travis CI master: [](https://travis-ci.org/libtom/libtommath) develop: [](https://travis-ci.org/libtom/libtommath) ### AppVeyor master: [](https://ci.appveyor.com/project/libtom/libtommath/branch/master) develop: [](https://ci.appveyor.com/project/libtom/libtommath/branch/develop) ### ABI Laboratory API/ABI changes: [check here](https://abi-laboratory.pro/tracker/timeline/libtommath/) ## Summary The `develop` branch contains the in-development version. Stable releases are tagged. Documentation is built from the LaTeX file `bn.tex`. There is also limited documentation in `tommath.h`. There is also a document, `tommath.pdf`, which describes the goals of the project and many of the algorithms used. The project can be build by using `make`. Along with the usual `make`, `make clean` and `make install`, there are several other build targets, see the makefile for details. There are also makefiles for certain specific platforms. ## Testing Tests are located in `demo/` and can be built in two flavors. * `make test` creates a stand-alone test binary that executes several test routines. * `make mtest_opponent` creates a test binary that is intended to be run against `mtest`. `mtest` can be built with `make mtest` and test execution is done like `./mtest/mtest | ./mtest_opponent`. `mtest` is creating test vectors using an alternative MPI library and `test` is consuming these vectors to verify correct behavior of ltm ## Building and Installing Building is straightforward for GNU Linux only, the section "Building LibTomMath" in the documentation in `doc/bn.pdf` has the details.