Top (The Libgcrypt Reference Manual)

This manual is for Libgcrypt (version 1.8.5, 19 November 2018), which is GNU’s library of cryptographic building blocks.

Short Table of Contents

• Introduction		What is Libgcrypt.
• Preparation		What you should do before using the library.
• Generalities		General library functions and data types.
• Handler Functions		Working with handler functions.
• Symmetric cryptography		How to use symmetric cryptography.
• Public Key cryptography		How to use public key cryptography.
• Hashing		How to use hash algorithms.
• Message Authentication Codes		How to use MAC algorithms.
• Key Derivation		How to derive keys from strings
• Random Numbers		How to work with random numbers.
• S-expressions		How to manage S-expressions.
• MPI library		How to work with multi-precision-integers.
• Prime numbers		How to use the Prime number related functions.
• Utilities		Utility functions.
• Tools		Utility tools.
• Configuration		Configuration files and environment variables.
• Architecture		How Libgcrypt works internally.
Appendices
• Self-Tests		Description of the self-tests.
• FIPS Mode		Description of the FIPS mode.
• Library Copying		The GNU Lesser General Public License says how you can copy and share Libgcrypt.
• Copying		The GNU General Public License says how you can copy and share some parts of Libgcrypt.
Indices
• Figures and Tables		Index of figures and tables.
• Concept Index		Index of concepts and programs.
• Function and Data Index		Index of functions, variables and data types.

1 Introduction
- 1.1 Getting Started
- 1.2 Features
- 1.3 Overview
2 Preparation
- 2.1 Header
- 2.2 Building sources
- 2.3 Building sources using Automake
- 2.4 Initializing the library
- 2.5 Multi-Threading
- 2.6 How to enable the FIPS mode
- 2.7 How to disable hardware features
3 Generalities
- 3.1 Controlling the library
- 3.2 Error Handling
4 Handler Functions
- 4.1 Progress handler
- 4.2 Allocation handler
- 4.3 Error handler
- 4.4 Logging handler
5 Symmetric cryptography
- 5.1 Available ciphers
- 5.2 Available cipher modes
- 5.3 Working with cipher handles
- 5.4 General cipher functions
6 Public Key cryptography
- 6.1 Available algorithms
- 6.2 Used S-expressions
- 6.3 Cryptographic Functions
- 6.4 General public-key related Functions
7 Hashing
- 7.1 Available hash algorithms
- 7.2 Working with hash algorithms
8 Message Authentication Codes
- 8.1 Available MAC algorithms
- 8.2 Working with MAC algorithms
9 Key Derivation
10 Random Numbers
- 10.1 Quality of random numbers
- 10.2 Retrieving random numbers
11 S-expressions
- 11.1 Data types for S-expressions
- 11.2 Working with S-expressions
12 MPI library
- 12.1 Data types
- 12.2 Basic functions
- 12.3 MPI formats
- 12.4 Calculations
- 12.5 Comparisons
- 12.6 Bit manipulations
- 12.7 EC functions
- 12.8 Miscellaneous
13 Prime numbers
- 13.1 Generation
- 13.2 Checking
14 Utilities
- 14.1 Memory allocation
- 14.2 Context management
- 14.3 Buffer description
- 14.4 How to return Libgcrypt’s configuration.
15 Tools
- 15.1 A HMAC-SHA-256 tool
16 Configuration files and environment variables
17 Architecture
- 17.1 Public-Key Architecture
- 17.2 Symmetric Encryption Subsystem Architecture
- 17.3 Hashing and MACing Subsystem Architecture
- 17.4 Multi-Precision-Integer Subsystem Architecture
- 17.5 Prime-Number-Generator Subsystem Architecture
- 17.6 Random-Number Subsystem Architecture
  - 17.6.1 Description of the CSPRNG
  - 17.6.2 Description of the FIPS X9.31 PRNG
Appendix A Description of the Self-Tests
- A.1 Power-Up Tests
- A.2 Conditional Tests
- A.3 Application Requested Tests
Appendix B Description of the FIPS Mode
- B.1 Restrictions in FIPS Mode
- B.2 FIPS Finite State Machine
- B.3 FIPS Miscellaneous Information
GNU Lesser General Public License
GNU General Public License
List of Figures and Tables
Concept Index
Function and Data Index

The Libgcrypt Reference Manual

The Libgcrypt Library

Short Table of Contents

Table of Contents