openssl/crypto/riscvcap.c
Henry Brausen 360f6dcc5a Add basic RISC-V cpuid and OPENSSL_riscvcap
RISC-V cpuid implementation allows bitmanip extensions Zb[abcs] to
be enabled at runtime using OPENSSL_riscvcap environment variable.

For example, to specify 64-bit RISC-V with the G,C,Zba,Zbb,Zbc
extensions, one could write: OPENSSL_riscvcap="rv64gc_zba_zbb_zbc"

Architecture string parsing is still very primitive, but can be
expanded in the future. Currently, only bitmanip extensions Zba, Zbb,
Zbc and Zbs are supported.

Includes implementation of constant-time CRYPTO_memcmp in riscv64 asm,
as well as OPENSSL_cleanse. Assembly implementations are written using
perlasm.

Reviewed-by: Philipp Tomsich <philipp.tomsich@vrull.eu>
Signed-off-by: Henry Brausen <henry.brausen@vrull.eu>

Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/17640)
2022-05-19 16:32:49 +10:00

87 lines
2.1 KiB
C

/*
* Copyright 2022 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
*/
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <stdint.h>
#include <openssl/crypto.h>
#include "internal/cryptlib.h"
#define OPENSSL_RISCVCAP_IMPL
#include "crypto/riscv_arch.h"
static void parse_env(const char *envstr);
static void strtoupper(char *str);
uint32_t OPENSSL_rdtsc(void)
{
return 0;
}
size_t OPENSSL_instrument_bus(unsigned int *out, size_t cnt)
{
return 0;
}
size_t OPENSSL_instrument_bus2(unsigned int *out, size_t cnt, size_t max)
{
return 0;
}
static void strtoupper(char *str)
{
for (char *x = str; *x; ++x)
*x = toupper(*x);
}
/* parse_env() parses a RISC-V architecture string. An example of such a string
* is "rv64gc_zba_zbb_zbc_zbs". Currently, the rv64gc part is ignored
* and we simply search for "_[extension]" in the arch string to see if we
* should enable a given extension.
*/
#define BUFLEN 256
static void parse_env(const char *envstr)
{
char envstrupper[BUFLEN];
char buf[BUFLEN];
/* Convert env str to all uppercase */
OPENSSL_strlcpy(envstrupper, envstr, sizeof(envstrupper));
strtoupper(envstrupper);
for (size_t i = 0; i < kRISCVNumCaps; ++i) {
/* Prefix capability with underscore in preparation for search */
BIO_snprintf(buf, BUFLEN, "_%s", RISCV_capabilities[i].name);
if (strstr(envstrupper, buf) != NULL) {
/* Match, set relevant bit in OPENSSL_riscvcap_P[] */
OPENSSL_riscvcap_P[RISCV_capabilities[i].index] |=
(1 << RISCV_capabilities[i].bit_offset);
}
}
}
# if defined(__GNUC__) && __GNUC__>=2
__attribute__ ((constructor))
# endif
void OPENSSL_cpuid_setup(void)
{
char *e;
static int trigger = 0;
if (trigger != 0)
return;
trigger = 1;
if ((e = getenv("OPENSSL_riscvcap"))) {
parse_env(e);
return;
}
}