| AES | Implementation of the NIST Advanced Encryption Standard ("AES"), FIPS 197 |
| Algorithm | Base class for tracking algorithm errors and internal system states |
| asn | Internal data type used for ASN.1 BER/DER encoding/decoding |
| Cert | Data type used for encoding and decoding individual X.509 certificates |
| certid | Data type used to detect matching certificates |
| Chain | Data type used for processing X.509 certificate chains |
| CMS1 | Data type used for in-memory PKCS #7 operations (RFC 3852 CMS) |
| CRC | Implementation of the IEEE 32-bit CRC |
| CRL | Data type used for creating and processing certificate revocation lists |
| Date | Data type used for date and time processing |
| DES | Implementation of the NIST Data Encryption Standard (DES, TDES, and variants), FIPS 46-3/81 |
| DName | Data type used for representing and processing X.500 distinguished names |
| EES | Implementation of the NIST EES ("Skipjack"), FIPS 185 |
| FParms | Data type used to specify arithmetic parameters for various rings and fields |
| GParms | Data type used to specify arithmetic parameters for various groups, including elliptic curves |
| GroupData | Data type used to store parameters for particular Abelian groups |
| ISC_CDK | Base class for FIPS 140-1 on-demand self-tests, error state tracking, and convenience utilities |
| Key | Class Key is the principal data type used for public and private keys and all related cryptographic operations |
| MD2 | Implementation of the RFC 1319 MD2 message digest |
| MD5 | Implementation of the RFC 1321 MD5 message digest |
| Nat | Data type used to represent elements of various algebraic objects |
| num | Implementation of the arithmetic in various groups, rings, and fields |
| Parameters | Base class for arithmetic parameters (used to define various algebraic structures) |
| party | Internal data type used by the implementation of class TLS to encapsulate various cryptographic operations |
| Password | Implementation of the NIST FIPS 181 Automated Password Generator |
| Point | Data type used to represent the elements of, and abstract the operations in, various Abelian groups, including elliptic curves |
| PRNG | Implementation of the NIST FIPS 186-2 Pseudorandom Number Generator |
| RC2 | Implementation of the RC2 symmetric block cipher |
| RC4 | Implementation of the RC4 stream cipher |
| recinfo | Lowest level data type used to process ASN.1 data |
| RSA | Implementation of RSA-based cryptographic schemes |
| SHA | Implementation of the NIST Secure Hash Algorithm (SHA/SHA-1), FIPS 180-1 |
| SHA2 | Implementation of the Extended NIST Secure Hash Algorithms (SHA-256/-384/-512), FIPS 180-2 |
| Signature | Data type used for digital signature operations |
| Signer | Data type used for CMS digital signature operations |
| str | Class str is somewhat similar to the STL std::string type |
| TLS | Data type used to implement SSLv2/TLS. For details, see RFC 2246 |
| tokenop | Data type used by callbacks to do private key operations, possibly on a hardware token |
