Botan: Crypto and TLS for C++11

Botan (Japanese for peony) is a C++ cryptography library released under the permissive Simplified BSD license. It provides useful things like TLS, X.509 certificates, ECDSA, AES, GCM, ChaCha20Poly1305, and bcrypt, plus a kitchen sink of other crypto algorithms of various utility; see the full list below.

Development is coordinated on GitHub and contributions are welcome.

For all the details on building the library, read the users manual, but basically:

$ ./configure.py --help
$ ./configure.py [probably some options]
$ make
$ ./botan-test
# lots of output...
Tests all ok
$ ./botan
# shows available commands
$ make install

If you need help or have questions, send a mail to the mailing list or open a ticket on GitHub Issues.

The GitHub wiki and Doxygen docs may also prove useful resources.

In addition to C++ there are (partial, in-progress) bindings for C89, Python and OCaml included along with the library, and Node.js wrapper also exists.

There is also a third party open source implementation of SSHv2 using the library.

https://travis-ci.org/randombit/botan.svg?branch=master https://ci.appveyor.com/api/projects/status/n9f94dljd03j2lce?svg=true https://botan-ci.kullo.net/badge https://coveralls.io/repos/randombit/botan/badge.svg?branch=master

Download

The 1.11 branch is highly recommended, especially for new development. But be warned the API is still subject to some change before the 2.0 stable release.

All releases are signed with a PGP key:

pub   2048R/EFBADFBC 2004-10-30
      Key fingerprint = 621D AF64 11E1 851C 4CF9  A2E1 6211 EBF1 EFBA DFBC
uid                  Botan Distribution Key

Botan may already be included in your favorite distribution, such as Fedora, EPEL (for RHEL/CentOS), Debian, Ubuntu, Gentoo, Arch, Slackbuild, FreeBSD ports, or MacPorts.

Current Development Series (1.11)

A new development release is made on the first Monday of every month.

The latest development release is 1.11.19 (sig) released 2015-08-03

Botan 1.11 requires a working C++11 compiler; GCC 4.8 and later, Clang 3.4 and later, and MSVC 2013 are regularly tested.

Current Stable Series (1.10)

The latest stable branch release is 1.10.10 (sig) released 2015-08-03

Botan 1.10 is the last version written in C++98.

Books and other resources

You should have some knowledge of cryptography before trying to use the library. This is an area where it is very easy to make mistakes, and where things are often subtle and/or counterintuitive. Obviously the library tries to provide things at a high level precisely to minimize the number of ways things can go wrong, but naive use will almost certainly not result in a secure system.

Especially recommended are:

  • Cryptography Engineering by Niels Ferguson, Bruce Schneier, and Tadayoshi Kohno
  • Security Engineering – A Guide to Building Dependable Distributed Systems by Ross Anderson
  • Handbook of Applied Cryptography by Alfred J. Menezes, Paul C. Van Oorschot, and Scott A. Vanstone (available online)

If you’re doing something non-trivial or unique, you might want to at the very least ask for review/input on a mailing list such as the metzdowd or randombit crypto lists. And (if possible) pay a professional cryptographer or security company to review your design and code.

Supported Algorithms/Protocols/RFCs

TLS/Public Key Infrastructure

  • TLS/DTLS (v1.0 to v1.2), including using preshared keys (TLS-PSK) or passwords (TLS-SRP) and most important extensions (including secure renegotiation, session tickets, SNI, and ALPN)
  • X.509 certificates (including generating new self-signed and CA certs) and CRLs
  • PKIX certificate path validation, OCSP requests, PKCS #10 CSRs

Public Key Cryptography

  • Encryption algorithms RSA and ElGamal (with OAEP or PKCS #1 v1.5)
  • Signature algorithms RSA, DSA, ECDSA, GOST 34.10-2001, Nyberg-Rueppel, Rabin-Williams (with PSS, PKCS #1 v1.5, or X9.31)
  • Diffie-Hellman, ECDH using NIST/Brainpool prime groups, Curve25519
  • McEliece code based encryption providing a KEM scheme

Ciphers and cipher modes

  • Authenticated cipher modes EAX, OCB, GCM, SIV, CCM, and ChaCha20Poly1305
  • Unauthenticated cipher modes CTR, CBC, XTS, CFB, OFB, and ECB
  • AES (including constant time SSSE3 and AES-NI versions)
  • AES candidates Serpent, Twofish, MARS, CAST-256, RC6
  • Stream ciphers Salsa20/XSalsa20, ChaCha20, and RC4
  • DES, 3DES and DESX
  • National/telecom block ciphers SEED, KASUMI, MISTY1, GOST 28147
  • Other block ciphers including Threefish-512, Blowfish, CAST-128, IDEA, Noekeon, TEA, XTEA, RC2, RC5, SAFER-SK
  • Large block cipher construction Lion

Hash functions and MACs

  • SHA-1, SHA-224, SHA-256, SHA-384, and SHA-512
  • SHA-3 winner Keccak-1600
  • SHA-3 candidate Skein-512
  • Authentication codes HMAC, CMAC, Poly1305, SipHash
  • RIPEMD-160, RIPEMD-128, Tiger, Whirlpool
  • Hash function combiners (Parallel and Comb4P)
  • National standard hashes HAS-160 and GOST 34.11
  • Non-cryptographic checksums Adler32, CRC24, CRC32
  • Obsolete algorithms MD5, MD4, MD2, CBC-MAC, X9.19 DES-MAC

Other Useful Things

  • Key derivation functions for passwords, including PBKDF2
  • Password hashing functions, including bcrypt
  • General key derivation functions KDF1 and KDF2 from IEEE 1363