VIA PadLock is a

central processing unit A central processing unit (CPU), also called a central processor, main processor or just processor, is the electronic circuitry that executes instructions comprising a computer program. The CPU performs basic arithmetic, logic, controlling, an ...

(CPU)

instruction set In computer science, an instruction set architecture (ISA), also called computer architecture, is an abstract model of a computer. A device that executes instructions described by that ISA, such as a central processing unit (CPU), is called an ' ...

extension to the

x86 x86 (also known as 80x86 or the 8086 family) is a family of complex instruction set computer (CISC) instruction set architectures initially developed by Intel based on the Intel 8086 microprocessor and its 8088 variant. The 8086 was introd ...

microprocessor A microprocessor is a computer processor where the data processing logic and control is included on a single integrated circuit, or a small number of integrated circuits. The microprocessor contains the arithmetic, logic, and control circu ...

instruction set architecture In computer science, an instruction set architecture (ISA), also called computer architecture, is an abstract model of a computer. A device that executes instructions described by that ISA, such as a central processing unit (CPU), is called an ' ...

(ISA) found on processors produced by

VIA Technologies VIA Technologies Inc. (), is a Taiwanese manufacturer of integrated circuits, mainly motherboard chipsets, CPUs, and memory. It was the world's largest independent manufacturer of motherboard chipsets. As a fabless semiconductor company, VIA c ...

and

Zhaoxin Zhaoxin (Shanghai Zhaoxin Semiconductor Co., Ltd.; , ) is a fabless semiconductor company, created in 2013 as a joint venture between VIA Technologies and the Shanghai Municipal Government. The company manufactures x86-compatible desktop and lap ...

. Introduced in 2003 with the VIA Centaur CPUs, the additional instructions provide hardware-accelerated

random number generation Random number generation is a process by which, often by means of a random number generator (RNG), a sequence of numbers or symbols that cannot be reasonably predicted better than by random chance is generated. This means that the particular outc ...

(RNG),

Advanced Encryption Standard The Advanced Encryption Standard (AES), also known by its original name Rijndael (), is a specification for the encryption of electronic data established by the U.S. National Institute of Standards and Technology (NIST) in 2001. AES is a variant ...

(AES),

SHA-1 In cryptography, SHA-1 (Secure Hash Algorithm 1) is a cryptographically broken but still widely used hash function which takes an input and produces a 160-bit (20-byte) hash value known as a message digest – typically rendered as 40 hexadecima ...

SHA256 SHA-2 (Secure Hash Algorithm 2) is a set of cryptographic hash functions designed by the United States National Security Agency (NSA) and first published in 2001. They are built using the Merkle–Damgård construction, from a one-way compression ...

, and

Montgomery modular multiplication In modular arithmetic computation, Montgomery modular multiplication, more commonly referred to as Montgomery multiplication, is a method for performing fast modular multiplication. It was introduced in 1985 by the American mathematician Peter Mon ...

Instructions

The PadLock instruction set can be divided into four subsets: *

Random number generation Random number generation is a process by which, often by means of a random number generator (RNG), a sequence of numbers or symbols that cannot be reasonably predicted better than by random chance is generated. This means that the particular outc ...

(RNG) ** XSTORE: Store Available Random Bytes (aka XSTORERNG) ** REP XSTORE: Store ECX Random Bytes * Advanced cryptography engine (ACE) - for AES crypto; two versions ** REP XCRYPTECB: Electronic code book ** REP XCRYPTCBC:

Cipher Block Chaining In cryptography, a block cipher mode of operation is an algorithm that uses a block cipher to provide information security such as confidentiality or authenticity. A block cipher by itself is only suitable for the secure cryptographic transforma ...

** REP XCRYPTCTR: Counter Mode (ACE2) ** REP XCRYPTCFB: Cipher Feedback Mode ** REP XCRYPTOFB: Output Feedback Mode * SHA hash engine (PHE) ** REP XSHA1: Hash Function SHA-1 ** REP XSHA256: Hash Function SHA-256 * Montgomery multiplier (PMM) ** REP MONTMUL The padlock capability is indicated via a

CPUID 

In the x86 architecture, the CPUID instruction (identified by a CPUID opcode) is a processor supplementary instruction (its name derived from  CPU IDentification) allowing software to discover details of the processor. It was introduced by Intel i ...

instruction with EAX = 0xC0000000. If the resultant EAX >= 0xC0000001, the CPU is aware of Centaur features. An additional request with EAX = 0xC0000001 then returns PadLock support in EDX. The padlock capability can be toggled on or off with MSR 0X1107. VIA PadLock found on some

CPUs have SM3 hashing and SM4 block cipher added.

CPUs with PadLock

* All VIA Nano CPUs support SHA, AES, and RNG. * All VIA Eden CPUs since 2003 (C3 Nehemiah) support AES and RNG. All these released since 2006 support AES, RNG, SHA, and PMM. * All VIA C7 CPUs support AES, RNG, SHA, and PMM.

Supporting software

Linux kernel The Linux kernel is a free and open-source, monolithic, modular, multitasking, Unix-like operating system kernel. It was originally authored in 1991 by Linus Torvalds for his i386-based PC, and it was soon adopted as the kernel for the GNU ope ...

since 2.6.11 has PadLock AES. PadLock SHA was introduced in 2.6.19. These are handled as "hardware crypto devices". *

OpenBSD OpenBSD is a security-focused, free and open-source, Unix-like operating system based on the Berkeley Software Distribution (BSD). Theo de Raadt created OpenBSD in 1995 by forking NetBSD 1.0. According to the website, the OpenBSD project em ...

and

FreeBSD FreeBSD is a free and open-source Unix-like operating system descended from the Berkeley Software Distribution (BSD), which was based on Research Unix. The first version of FreeBSD was released in 1993. In 2005, FreeBSD was the most popular ...

support PadLock. *

OpenSSL OpenSSL is a software library for applications that provide secure communications over computer networks against eavesdropping or need to identify the party at the other end. It is widely used by Internet servers, including the majority of HTT ...

supports PadLock AES and SHA since 2004 (0.9.7f/0.9.8a). *

GNU assembler The GNU Assembler, commonly known as gas or as, is the assembler developed by the GNU Project. It is the default back-end of GCC. It is used to assemble the GNU operating system and the Linux kernel, and various other software. It is a part of ...

supports PadLock since 2004.

References

{{Cryptography block Instruction processing X86 architecture

PadLock Padlocks are portable locks with a shackle that may be passed through an opening (such as a chain link, or hasp staple) to prevent use, theft, vandalism or harm. Naming and etymology The term ''padlock'' is from the late fifteenth century. T ...

Instructions

CPUs with PadLock

Supporting software

See also

References