Botan (Japanese for peony) is a cryptography library written in C++11 and released under the permissive Simplified BSD license.
Botan's goal is to be the best option for cryptography in new C++ code by offering the tools necessary to implement a range of practical systems, such as TLS/DTLS, PKIX certificate handling, PKCS#11 and TPM hardware support, password hashing, and post quantum crypto schemes. Find the full feature list below.
Development is coordinated on GitHub and contributions are welcome (read doc/contributing.rst for more info).
If you need help, open a GitHub issue, email the mailing list, or try the botan gitter.im channel.
If you think you've found a security bug, read the security page for contact information and procedures.
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
The library can also be built into a single-file amalgamation for easy inclusion into external build systems.
In addition to C++, botan has a C89 API specifically designed to be easy to call from other languages. A Python binding using ctypes is included.
See the change notes and security page
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
Some distributions such as Arch, Fedora and Debian include packages for Botan. However these are often out of date; using the latest source release is recommended.
Version 2 requires a C++11 compiler; GCC 4.8 and later, Clang 3.5 and later, and MSVC 2015 are regularly tested.
The latest 2.x release is 2.0.0 (sig) released on 2017-01-06
The 1.10 branch is the last version of the library written in C++98 and is still the most commonly packaged version. It is no longer supported except for critical security updates (with all support ending on 2018-1-1), and the developers do not recommend its use anymore.
The latest 1.10 release is 1.10.14 (sig) released on 2016-11-28
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 (available online)
- 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.
- TLS v1.0, v1.1, and v1.2. The broken SSLv3 protocol is no longer supported.
- DTLS v1.0 and v1.2 are adaptations of TLS to datagram operation.
- Extensions include session tickets, SNI, ALPN, OCSP staple requests (client side only right now), encrypt-then-mac CBC, and extended master secret.
- Supports authentication using preshared keys (PSK) or passwords (SRP)
- Supports record encryption with ChaCha20Poly1305, AES/OCB, AES/GCM, AES/CCM, Camellia/GCM, and legacy CBC ciphersuites with AES, Camellia, SEED, or 3DES.
- Key exchange using Diffie-Hellman, ECDH, RSA, or CECPQ1
- X.509v3 certificates and CRL creation and handling
- PKIX certificate path validation, including name constraints.
- OCSP request creation and response handling
- PKCS #10 certificate request generation and processing
- SQL database backed certificate store
- RSA signatures and encryption
- DH and ECDH key agreement
- Signature schemes ECDSA, DSA, ECGDSA, ECKCDSA, and GOST 34.10-2001
- Post-quantum signature scheme XMSS
- Post-quantum key agreement schemes McEliece and NewHope
- ElGamal encryption
- Padding schemes OAEP, PSS, PKCS #1 v1.5, X9.31
- Authenticated cipher modes EAX, OCB, GCM, SIV, CCM, and ChaCha20Poly1305
- Cipher modes CTR, CBC, XTS, CFB, and OFB
- Block ciphers AES, Serpent, Blowfish, Twofish, Threefish-512, DES/3DES, Noekeon, IDEA, CAST-128, XTEA, SEED, KASUMI, GOST 28147, MISTY1, Lion, CAST-256
- Stream ciphers ChaCha20, Salsa20/XSalsa20, SHAKE-128, and RC4
- Hash functions SHA-1, SHA-2, SHA-3, RIPEMD-160, Skein-512, BLAKE2b, Tiger, Whirlpool, GOST 34.11, MD5, MD4
- Hash function combiners Parallel and Comb4P
- Authentication codes HMAC, CMAC, Poly1305, SipHash, GMAC, CBC-MAC, X9.19 DES-MAC
- Non-cryptographic checksums Adler32, CRC24, and CRC32
- Full C++ PKCS #11 API wrapper
- Interfaces for TPM v1.2 device access
- Simple compression API wrapping zlib, bzip2, and lzma libraries
- RNG wrappers for system RNG and hardware RNGs
- HMAC_DRBG and entropy collection system for userspace RNGs
- PBKDF2 password based key derivation
- Password hashing function bcrypt and passhash9 (custom PBKDF scheme)
- SRP-6a password authenticated key exchange
- Key derivation functions including HKDF, KDF2, SP 800-108, SP 800-56C
- Format preserving encryption scheme FE1
- Threshold secret sharing
- RFC 3394 AES key wrap
- For encryption of network traffic use TLS v1.2
- Packet encryption: AES-256/GCM, AES-256/OCB, Serpent/OCB, or ChaCha20Poly1305
- General hash function: BLAKE2b, SHA-2, SHA-3, or Skein-512
- Message authentication or PRF: HMAC with SHA-256
- Key derivation function: KDF2 or HKDF
- Public Key Encryption: RSA, 2048+ bit keys, with OAEP/SHA-256
- Public Key Signatures: RSA, 2048+ bit keys with PSS/SHA-512, or ECDSA using P-256/SHA-256 or P-521/SHA-512
- Key Agreement: ECDH using P-256 or X25519. If you are concerned about quantum computers, combine ECC with NewHope.
