Botan: Crypto and TLS for Modern C++

Botan (Japanese for peony flower) is a C++ cryptography library released under the permissive Simplified BSD license.

Botan's goal is to be the best option for cryptography in C++ by offering the tools necessary to implement a range of practical systems, such as TLS protocol, X.509 certificates, modern AEAD ciphers, PKCS#11 and TPM hardware support, password hashing, and post quantum crypto schemes. A Python binding is included, and several other language bindings are available. It is used in many open source and commercial products. The library is accompanied by a featureful command line interface.

See the documentation for more information about included features.

Development is coordinated on GitHub and contributions are welcome. If you need help, please open an issue on GitHub or email the botan-devel mailing list. New releases are announced on the botan-announce mailing list. If you think you have found a security issue, see the security page for contact information.

The latest release is 2.19.2 (sig), released on 2022-06-03. All releases are signed with a PGP key. See the release notes for what is new. Botan is also available through most distributions such as Fedora, Debian, Arch and Homebrew.

Find Enclosed

Transport Layer Security (TLS) Protocol

TLS v1.2 and DTLS v1.2
Supported extensions include session tickets, SNI, ALPN, OCSP stapling, encrypt-then-mac CBC, and extended master secret.
Supports authentication using certificates or preshared keys (PSK)
Supports record encryption with ChaCha20Poly1305, AES/OCB, AES/GCM, AES/CCM, Camellia/GCM as well as legacy CBC ciphersuites.
Key exchange using CECPQ1, ECDH, FFDHE, or RSA

Public Key Infrastructure

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
Access to Windows, macOS and Unix system certificate stores
SQL database backed certificate store

Public Key Cryptography

RSA signatures and encryption
DH and ECDH key agreement
Signature schemes ECDSA, DSA, Ed25519, ECGDSA, ECKCDSA, SM2, GOST 34.10
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

Ciphers, hashes, MACs, and checksums

Authenticated cipher modes EAX, OCB, GCM, SIV, CCM, (X)ChaCha20Poly1305
Cipher modes CTR, CBC, XTS, CFB, OFB
Block ciphers AES, ARIA, Blowfish, Camellia, CAST-128, DES/3DES, IDEA, Lion, SEED, Serpent, SHACAL2, SM4, Threefish-512, Twofish
Stream ciphers (X)ChaCha20, (X)Salsa20, SHAKE-128, RC4
Hash functions SHA-1, SHA-2, SHA-3, MD5, RIPEMD-160, BLAKE2b, Skein-512, SM3, Streebog, Whirlpool
Authentication codes HMAC, CMAC, Poly1305, SipHash, GMAC, X9.19 DES-MAC
Non-cryptographic checksums Adler32, CRC24, CRC32

Other Useful Things

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
Password hashing schemes PBKDF2, Argon2, Scrypt, bcrypt
SRP-6a password authenticated key exchange
Key derivation functions including HKDF, KDF2, SP 800-108, SP 800-56A, SP 800-56C
HOTP and TOTP algorithms
Format preserving encryption scheme FE1
Threshold secret sharing
NIST key wrapping
Boost.Asio compatible TLS client stream