Installation

You can install cryptography with pip:

$ pip install cryptography

If this does not work please upgrade your pip first, as that is the single most common cause of installation problems.

Supported platforms

Currently we test cryptography on Python 3.6+ and PyPy3 7.3.1 on these operating systems.

  • x86-64 CentOS 8.x

  • x86-64 Fedora (latest)

  • x86-64 macOS 10.15 Catalina

  • x86-64 Ubuntu 18.04, 20.04

  • AArch64 Ubuntu 20.04

  • x86-64 Ubuntu rolling

  • x86-64 Debian Stretch (9.x), Buster (10.x), Bullseye (11.x), Bookworm (12.x) and Sid (unstable)

  • x86-64 Alpine (latest)

  • 32-bit and 64-bit Python on 64-bit Windows Server 2019

We test compiling with clang as well as gcc and use the following OpenSSL releases:

  • OpenSSL 1.1.0-latest

  • OpenSSL 1.1.1-latest

  • OpenSSL 3.0-latest

Building cryptography on Windows

The wheel package on Windows is a statically linked build (as of 0.5) so all dependencies are included. To install cryptography, you will typically just run

$ pip install cryptography

If you prefer to compile it yourself you’ll need to have OpenSSL installed. You can compile OpenSSL yourself as well or use a binary distribution. Be sure to download the proper version for your architecture and Python (VC2015 is required for 3.6 and above). Wherever you place your copy of OpenSSL you’ll need to set the LIB and INCLUDE environment variables to include the proper locations. For example:

C:\> \path\to\vcvarsall.bat x86_amd64
C:\> set LIB=C:\OpenSSL-win64\lib;%LIB%
C:\> set INCLUDE=C:\OpenSSL-win64\include;%INCLUDE%
C:\> pip install cryptography

As of OpenSSL 1.1.0 the library names have changed from libeay32 and ssleay32 to libcrypto and libssl (matching their names on all other platforms). cryptography links against the new 1.1.0 names by default. If you need to compile cryptography against an older version then you must set CRYPTOGRAPHY_WINDOWS_LINK_LEGACY_OPENSSL or else installation will fail.

You will also need to have Rust installed and available.

If you need to rebuild cryptography for any reason be sure to clear the local wheel cache.

Building cryptography on Linux

Note

If you are on RHEL/CentOS/Fedora/Debian/Ubuntu or another distribution derived from the preceding list, then you should upgrade pip and attempt to install cryptography again before following the instructions to compile it below. These platforms will receive a binary wheel and require no compiler if you have an updated pip!

cryptography ships manylinux wheels (as of 2.0) so all dependencies are included. For users on pip 19.0 or above running on a manylinux2010 (or greater) compatible distribution (or pip 21.2.4 for musllinux) all you should need to do is:

$ pip install cryptography

If you want to compile cryptography yourself you’ll need a C compiler, a Rust compiler, headers for Python (if you’re not using pypy), and headers for the OpenSSL and libffi libraries available on your system.

On all Linux distributions you will need to have Rust installed and available.

Alpine

Warning

The Rust available by default in Alpine < 3.12 is older than the minimum supported version. See the Rust installation instructions for information about installing a newer Rust.

$ sudo apk add gcc musl-dev python3-dev libffi-dev openssl-dev cargo

If you get an error with openssl-dev you may have to use libressl-dev.

Debian/Ubuntu

Warning

The Rust available in current Debian stable and some Ubuntu versions is older than the minimum supported version. Ubuntu 18.04 and 20.04 are sufficiently new, but otherwise please see the Rust installation instructions for information about installing a newer Rust.

$ sudo apt-get install build-essential libssl-dev libffi-dev \
    python3-dev cargo

Fedora/RHEL 8/CentOS 8

Warning

For RHEL and CentOS you must be on version 8.3 or newer for the command below to install a sufficiently new Rust. If your Rust is less than 1.41.0 please see the Rust installation instructions for information about installing a newer Rust.

$ sudo dnf install redhat-rpm-config gcc libffi-devel python3-devel \
    openssl-devel cargo

RHEL 7/CentOS 7

Warning

You must install Rust using the Rust installation instructions. cryptography requires a Rust version newer than what is provided in the distribution packages.

$ sudo yum install redhat-rpm-config gcc libffi-devel python-devel \
    openssl-devel

Building

You should now be able to build and install cryptography. To avoid getting the pre-built wheel on manylinux compatible distributions you’ll need to use --no-binary.

$ pip install cryptography --no-binary cryptography

Using your own OpenSSL on Linux

Python links to OpenSSL for its own purposes and this can sometimes cause problems when you wish to use a different version of OpenSSL with cryptography. If you want to use cryptography with your own build of OpenSSL you will need to make sure that the build is configured correctly so that your version of OpenSSL doesn’t conflict with Python’s.

The options you need to add allow the linker to identify every symbol correctly even when multiple versions of the library are linked into the same program. If you are using your distribution’s source packages these will probably be patched in for you already, otherwise you’ll need to use options something like this when configuring OpenSSL:

$ ./config -Wl,-Bsymbolic-functions -fPIC shared

Static Wheels

Cryptography ships statically-linked wheels for macOS, Windows, and Linux (via manylinux and musllinux). This allows compatible environments to use the most recent OpenSSL, regardless of what is shipped by default on those platforms.

If you are using a platform not covered by our wheels, you can build your own statically-linked wheels that will work on your own systems. This will allow you to continue to use relatively old Linux distributions (such as LTS releases), while making sure you have the most recent OpenSSL available to your Python programs.

To do so, you should find yourself a machine that is as similar as possible to your target environment (e.g. your production environment): for example, spin up a new cloud server running your target Linux distribution. On this machine, install the Cryptography dependencies as mentioned in Building cryptography on Linux. Please also make sure you have virtualenv installed: this should be available from your system package manager.

Then, paste the following into a shell script. You’ll need to populate the OPENSSL_VERSION variable. To do that, visit openssl.org and find the latest non-FIPS release version number, then set the string appropriately. For example, for OpenSSL 1.0.2k, use OPENSSL_VERSION="1.0.2k".

When this shell script is complete, you’ll find a collection of wheel files in a directory called wheelhouse. These wheels can be installed by a sufficiently-recent version of pip. The Cryptography wheel in this directory contains a statically-linked OpenSSL binding, which ensures that you have access to the most-recent OpenSSL releases without corrupting your system dependencies.

set -e

OPENSSL_VERSION="VERSIONGOESHERE"
CWD=$(pwd)

virtualenv env
. env/bin/activate
pip install -U setuptools
pip install -U wheel pip
curl -O https://www.openssl.org/source/openssl-${OPENSSL_VERSION}.tar.gz
tar xvf openssl-${OPENSSL_VERSION}.tar.gz
cd openssl-${OPENSSL_VERSION}
./config no-shared no-ssl2 no-ssl3 -fPIC --prefix=${CWD}/openssl
make && make install
cd ..
CFLAGS="-I${CWD}/openssl/include" LDFLAGS="-L${CWD}/openssl/lib" pip wheel --no-binary :all: cryptography

Building cryptography on macOS

Note

If installation gives a fatal error: 'openssl/aes.h' file not found see the FAQ for information about how to fix this issue.

The wheel package on macOS is a statically linked build (as of 1.0.1) so for users with pip 8 or above you only need one step:

$ pip install cryptography

If you want to build cryptography yourself or are on an older macOS version, cryptography requires the presence of a C compiler, development headers, and the proper libraries. On macOS much of this is provided by Apple’s Xcode development tools. To install the Xcode command line tools (on macOS 10.10+) open a terminal window and run:

$ xcode-select --install

This will install a compiler (clang) along with (most of) the required development headers.

You will also need to have Rust installed and available, which can be obtained from Homebrew, MacPorts, or directly from the Rust website.

Finally you need OpenSSL, which you can obtain from Homebrew or MacPorts. Cryptography does not support the OpenSSL/LibreSSL libraries Apple ships in its base operating system.

To build cryptography and dynamically link it:

Homebrew

$ brew install openssl@1.1 rust
$ env LDFLAGS="-L$(brew --prefix openssl@1.1)/lib" CFLAGS="-I$(brew --prefix openssl@1.1)/include" pip install cryptography

MacPorts:

$ sudo port install openssl rust
$ env LDFLAGS="-L/opt/local/lib" CFLAGS="-I/opt/local/include" pip install cryptography

You can also build cryptography statically:

Homebrew

$ brew install openssl@1.1 rust
$ env CRYPTOGRAPHY_SUPPRESS_LINK_FLAGS=1 LDFLAGS="$(brew --prefix openssl@1.1)/lib/libssl.a $(brew --prefix openssl@1.1)/lib/libcrypto.a" CFLAGS="-I$(brew --prefix openssl@1.1)/include" pip install cryptography

MacPorts:

$ sudo port install openssl rust
$ env CRYPTOGRAPHY_SUPPRESS_LINK_FLAGS=1 LDFLAGS="/opt/local/lib/libssl.a /opt/local/lib/libcrypto.a" CFLAGS="-I/opt/local/include" pip install cryptography

If you need to rebuild cryptography for any reason be sure to clear the local wheel cache.

Rust

Note

If you are using Linux, then you should upgrade pip (in a virtual environment!) and attempt to install cryptography again before trying to install the Rust toolchain. On most Linux distributions, the latest version of pip will be able to install a binary wheel, so you won’t need a Rust toolchain.

Building cryptography requires having a working Rust toolchain. The current minimum supported Rust version is 1.41.0. This is newer than the Rust most package managers ship, so users will likely need to install with the instructions below.

Instructions for installing Rust can be found on the Rust Project’s website. We recommend installing Rust with rustup (as documented by the Rust Project) in order to ensure you have a recent version.

Rust is only required when building cryptography, meaning that you may install it for the duration of your pip install command and then remove it from a system. A Rust toolchain is not required to use cryptography. In deployments such as docker, you may use a multi-stage Dockerfile where you install Rust during the build phase but do not install it in the runtime image. This is the same as the C compiler toolchain which is also required to build cryptography, but not afterwards.