OPENSSL_RISCVCAP(3ossl) OpenSSL OPENSSL_RISCVCAP(3ossl)
NAME
OPENSSL_riscvcap - the RISC-V processor capabilities vector
SYNOPSIS
env OPENSSL_riscvcap=... <application>
DESCRIPTION
libcrypto supports RISC-V instruction set extensions. These extensions
are denoted by individual extension names in the capabilities vector.
For Linux platform, when libcrypto is initialized, the results returned
by the RISC-V Hardware Probing syscall (hwprobe) are stored in the
vector. Otherwise all capabilities are disabled.
To override the set of instructions available to an application, you
can set the OPENSSL_riscvcap environment variable before you start the
application.
The environment variable is similar to the RISC-V ISA string defined in
the RISC-V Instruction Set Manual. It is case insensitive. Though due
to the limit of the environment variable parser inside libcrypto, an
extension must be prefixed with an underscore to make it recognizable.
This also applies to the Vector extension.
OPENSSL_riscvcap="rv64gc_v_zba_zbb_zbs..."
Note that extension implication is currently not implemented. For
example, when "rv64gc_b" is provided as the environment variable,
zba/zbb/zbs would not be implied in the capability vector.
Currently only these extensions are recognized:
ZBA Address Generation
Could be detected using hwprobe for Linux kernel >= 6.5
ZBB Basic bit-manipulation
Could be detected using hwprobe for Linux kernel >= 6.5
ZBC Carry-less multiplication
Could be detected using hwprobe for Linux kernel >= 6.8
ZBS Single-bit instructions
Could be detected using hwprobe for Linux kernel >= 6.5
ZBKB
Bit-manipulation for Cryptography
Could be detected using hwprobe for Linux kernel >= 6.8
ZBKC
Carry-less multiplication for Cryptography
Could be detected using hwprobe for Linux kernel >= 6.8
ZBKX
Crossbar permutations
Could be detected using hwprobe for Linux kernel >= 6.8
ZKND
NIST Suite: AES Decryption
Could be detected using hwprobe for Linux kernel >= 6.8
ZKNE
NIST Suite: AES Encryption
Could be detected using hwprobe for Linux kernel >= 6.8
ZKNH
NIST Suite: Hash Function Instructions
Could be detected using hwprobe for Linux kernel >= 6.8
ZKSED
ShangMi Suite: SM4 Block Cipher Instructions
Could be detected using hwprobe for Linux kernel >= 6.8
ZKSH
ShangMi Suite: SM3 Hash Function Instructions
Could be detected using hwprobe for Linux kernel >= 6.8
ZKR Entropy Source Extension
ZKT Data Independent Execution Latency
Could be detected using hwprobe for Linux kernel >= 6.8
V Vector Extension for Application Processors
Could be detected using hwprobe for Linux kernel >= 6.5
ZVBB
Vector Basic Bit-manipulation
Could be detected using hwprobe for Linux kernel >= 6.8
ZVBC
Vector Carryless Multiplication
Could be detected using hwprobe for Linux kernel >= 6.8
ZVKB
Vector Cryptography Bit-manipulation
Could be detected using hwprobe for Linux kernel >= 6.8
ZVKG
Vector GCM/GMAC
Could be detected using hwprobe for Linux kernel >= 6.8
ZVKNED
NIST Suite: Vector AES Block Cipher
Could be detected using hwprobe for Linux kernel >= 6.8
ZVKNHA
NIST Suite: Vector SHA-2 Secure Hash
Could be detected using hwprobe for Linux kernel >= 6.8
ZVKNHB
NIST Suite: Vector SHA-2 Secure Hash
Could be detected using hwprobe for Linux kernel >= 6.8
ZVKSED
ShangMi Suite: SM4 Block Cipher
Could be detected using hwprobe for Linux kernel >= 6.8
ZVKSH
ShangMi Suite: SM3 Secure Hash
Could be detected using hwprobe for Linux kernel >= 6.8
RETURN VALUES
Not available.
EXAMPLES
Check currently detected capabilities
$ openssl info -cpusettings
OPENSSL_riscvcap=ZBA_ZBB_ZBC_ZBS_V
Disables all instruction set extensions:
OPENSSL_riscvcap="rv64gc"
Only enable the vector extension:
OPENSSL_riscvcap="rv64gc_v"
COPYRIGHT
Copyright 2024 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the Apache License 2.0 (the "License"). You may not use
this file except in compliance with the License. You can obtain a copy
in the file LICENSE in the source distribution or at
<https://www.openssl.org/source/license.html>.
3.4.0 2024-10-29 OPENSSL_RISCVCAP(3ossl)
openssl 3.4.0 - Generated Sat Nov 9 06:56:18 CST 2024